FileDocCategorySizeDatePackage
Container.javaAPI DocJava SE 6 API166195Tue Jun 10 00:25:14 BST 2008java.awt

Container

public class Container extends Component
A generic Abstract Window Toolkit(AWT) container object is a component that can contain other AWT components.

Components added to a container are tracked in a list. The order of the list will define the components' front-to-back stacking order within the container. If no index is specified when adding a component to a container, it will be added to the end of the list (and hence to the bottom of the stacking order).

Note: For details on the focus subsystem, see How to Use the Focus Subsystem, a section in The Java Tutorial, and the Focus Specification for more information.

version
1.286, 07/27/06
author
Arthur van Hoff
author
Sami Shaio
see
#add(java.awt.Component, int)
see
#getComponent(int)
see
LayoutManager
since
JDK1.0

Fields Summary
int
ncomponents
The number of components in this container. This value can be null.
Component[]
component
The components in this container.
LayoutManager
layoutMgr
Layout manager for this container.
private LightweightDispatcher
dispatcher
Event router for lightweight components. If this container is native, this dispatcher takes care of forwarding and retargeting the events to lightweight components contained (if any).
private transient FocusTraversalPolicy
focusTraversalPolicy
The focus traversal policy that will manage keyboard traversal of this Container's children, if this Container is a focus cycle root. If the value is null, this Container inherits its policy from its focus-cycle- root ancestor. If all such ancestors of this Container have null policies, then the current KeyboardFocusManager's default policy is used. If the value is non-null, this policy will be inherited by all focus-cycle-root children that have no keyboard-traversal policy of their own (as will, recursively, their focus-cycle-root children).

If this Container is not a focus cycle root, the value will be remembered, but will not be used or inherited by this or any other Containers until this Container is made a focus cycle root.

private boolean
focusCycleRoot
Indicates whether this Component is the root of a focus traversal cycle. Once focus enters a traversal cycle, typically it cannot leave it via focus traversal unless one of the up- or down-cycle keys is pressed. Normal traversal is limited to this Container, and all of this Container's descendants that are not descendants of inferior focus cycle roots.
private boolean
focusTraversalPolicyProvider
Stores the value of focusTraversalPolicyProvider property.
private transient Set
printingThreads
private transient boolean
printing
transient ContainerListener
containerListener
transient int
listeningChildren
transient int
listeningBoundsChildren
transient int
descendantsCount
private static final long
serialVersionUID
JDK 1.1 serialVersionUID
private static final sun.awt.DebugHelper
dbg
static final boolean
INCLUDE_SELF
A constant which toggles one of the controllable behaviors of getMouseEventTarget. It is used to specify whether the method can return the Container on which it is originally called in case if none of its children are the current mouse event targets.
static final boolean
SEARCH_HEAVYWEIGHTS
A constant which toggles one of the controllable behaviors of getMouseEventTarget. It is used to specify whether the method should search only lightweight components.
private static final ObjectStreamField[]
serialPersistentFields
transient Component
modalComp
transient AppContext
modalAppContext
private int
containerSerializedDataVersion
Container Serial Data Version.
Constructors Summary
public Container()
Constructs a new Container. Containers can be extended directly, but are lightweight in this case and must be contained by a parent somewhere higher up in the component tree that is native. (such as Frame for example).


     
        /* ensure that the necessary native libraries are loaded */
	Toolkit.loadLibraries();
        if (!GraphicsEnvironment.isHeadless()) {
            initIDs();
        }
    
    
Methods Summary
public java.awt.Componentadd(java.awt.Component comp)
Appends the specified component to the end of this container. This is a convenience method for {@link #addImpl}.

Note: If a component has been added to a container that has been displayed, validate must be called on that container to display the new component. If multiple components are being added, you can improve efficiency by calling validate only once, after all the components have been added.

param
comp the component to be added
exception
NullPointerException if {@code comp} is {@code null}
see
#addImpl
see
#validate
see
javax.swing.JComponent#revalidate()
return
the component argument

        addImpl(comp, null, -1);
	return comp;
    
public java.awt.Componentadd(java.lang.String name, java.awt.Component comp)
Adds the specified component to this container. This is a convenience method for {@link #addImpl}.

This method is obsolete as of 1.1. Please use the method add(Component, Object) instead.

exception
NullPointerException if {@code comp} is {@code null}
see
#add(Component, Object)

	addImpl(comp, name, -1);
	return comp;
    
public java.awt.Componentadd(java.awt.Component comp, int index)
Adds the specified component to this container at the given position. This is a convenience method for {@link #addImpl}.

Note: If a component has been added to a container that has been displayed, validate must be called on that container to display the new component. If multiple components are being added, you can improve efficiency by calling validate only once, after all the components have been added.

param
comp the component to be added
param
index the position at which to insert the component, or -1 to append the component to the end
exception
NullPointerException if {@code comp} is {@code null}
exception
IllegalArgumentException if {@code index} is invalid (see {@link #addImpl} for details)
return
the component comp
see
#addImpl
see
#remove
see
#validate
see
javax.swing.JComponent#revalidate()

	addImpl(comp, null, index);
	return comp;
    
public voidadd(java.awt.Component comp, java.lang.Object constraints)
Adds the specified component to the end of this container. Also notifies the layout manager to add the component to this container's layout using the specified constraints object. This is a convenience method for {@link #addImpl}.

Note: If a component has been added to a container that has been displayed, validate must be called on that container to display the new component. If multiple components are being added, you can improve efficiency by calling validate only once, after all the components have been added.

param
comp the component to be added
param
constraints an object expressing layout contraints for this component
exception
NullPointerException if {@code comp} is {@code null}
see
#addImpl
see
#validate
see
javax.swing.JComponent#revalidate()
see
LayoutManager
since
JDK1.1

	addImpl(comp, constraints, -1);
    
public voidadd(java.awt.Component comp, java.lang.Object constraints, int index)
Adds the specified component to this container with the specified constraints at the specified index. Also notifies the layout manager to add the component to the this container's layout using the specified constraints object. This is a convenience method for {@link #addImpl}.

Note: If a component has been added to a container that has been displayed, validate must be called on that container to display the new component. If multiple components are being added, you can improve efficiency by calling validate only once, after all the components have been added.

param
comp the component to be added
param
constraints an object expressing layout contraints for this
param
index the position in the container's list at which to insert the component; -1 means insert at the end component
exception
NullPointerException if {@code comp} is {@code null}
exception
IllegalArgumentException if {@code index} is invalid (see {@link #addImpl} for details)
see
#addImpl
see
#validate
see
javax.swing.JComponent#revalidate()
see
#remove
see
LayoutManager

       addImpl(comp, constraints, index);
    
public synchronized voidaddContainerListener(java.awt.event.ContainerListener l)
Adds the specified container listener to receive container events from this container. If l is null, no exception is thrown and no action is performed.

Refer to AWT Threading Issues for details on AWT's threading model.

param
l the container listener
see
#removeContainerListener
see
#getContainerListeners

	if (l == null) {
	    return;
	}
	containerListener = AWTEventMulticaster.add(containerListener, l);
        newEventsOnly = true;	
    
private voidaddDelicately(java.awt.Component comp, java.awt.Container curParent, int index)
Adds component to this container. Tries to minimize side effects of this adding - doesn't call remove notify if it is not required.

since
1.5

        checkTreeLock();

        // Check if moving between containers
        if (curParent != this) {
            /* Add component to list; allocate new array if necessary. */
            if (ncomponents == component.length) {
                component = Arrays.copyOf(component, ncomponents * 2 + 1);
            }
            if (index == -1 || index == ncomponents) {
                component[ncomponents++] = comp;
            } else {
                System.arraycopy(component, index, component,
                                 index + 1, ncomponents - index);
                component[index] = comp;
                ncomponents++;
            }
            comp.parent = this;

            adjustListeningChildren(AWTEvent.HIERARCHY_EVENT_MASK, 
                                    comp.numListening(AWTEvent.HIERARCHY_EVENT_MASK));
            adjustListeningChildren(AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK,
                                    comp.numListening(AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK));
            adjustDescendants(comp.countHierarchyMembers());
        } else {
            if (index < ncomponents) {
                component[index] = comp;
            }
        }

        if (valid) {
            invalidate();
        }
        if (peer != null) {
            if (comp.peer == null) { // Remove notify was called or it didn't have peer - create new one
                comp.addNotify();
                // New created peer creates component on top of the stacking order
                Container newNativeContainer = getHeavyweightContainer();
                if (((ContainerPeer)newNativeContainer.getPeer()).isRestackSupported()) {
                    ((ContainerPeer)newNativeContainer.getPeer()).restack();
                }
            } else { // Both container and child have peers, it means child peer should be reparented.
                // In both cases we need to reparent native widgets.
                Container newNativeContainer = getHeavyweightContainer();
                Container oldNativeContainer = curParent.getHeavyweightContainer();
                if (oldNativeContainer != newNativeContainer) {
                    // Native container changed - need to reparent native widgets
                    newNativeContainer.reparentChild(comp);
                }
                // If component still has a peer and it is either container or heavyweight
                // and restack is supported we have to restack native windows since order might have changed
                if ((!comp.isLightweight() || (comp instanceof Container)) 
                    && ((ContainerPeer)newNativeContainer.getPeer()).isRestackSupported()) 
                {
                    ((ContainerPeer)newNativeContainer.getPeer()).restack();
                }
                if (!comp.isLightweight() && isLightweight()) {
                    // If component is heavyweight and one of the containers is lightweight
                    // some NativeInLightFixer activity should be performed
                    if (!curParent.isLightweight()) {
                        // Moving from heavyweight container to lightweight container - should create NativeInLightFixer
                        // since addNotify does this
                        comp.nativeInLightFixer = new NativeInLightFixer();
                    } else {
                        // Component already has NativeInLightFixer - just reinstall it
                        // because hierarchy changed and he needs to rebuild list of parents to listen.
                        comp.nativeInLightFixer.install(this);
                    }
                }
            }
        }
        if (curParent != this) {
            /* Notify the layout manager of the added component. */
            if (layoutMgr != null) {
                if (layoutMgr instanceof LayoutManager2) {
                    ((LayoutManager2)layoutMgr).addLayoutComponent(comp, null);
                } else {
                    layoutMgr.addLayoutComponent(null, comp);
                }
            }
            if (containerListener != null || 
                (eventMask & AWTEvent.CONTAINER_EVENT_MASK) != 0 ||
                Toolkit.enabledOnToolkit(AWTEvent.CONTAINER_EVENT_MASK)) {
                ContainerEvent e = new ContainerEvent(this, 
                                                      ContainerEvent.COMPONENT_ADDED,
                                                      comp);
                dispatchEvent(e);
            }
            comp.createHierarchyEvents(HierarchyEvent.HIERARCHY_CHANGED, comp,
                                       this, HierarchyEvent.PARENT_CHANGED,
                                       Toolkit.enabledOnToolkit(AWTEvent.HIERARCHY_EVENT_MASK));

            // If component is focus owner or parent container of focus owner check that after reparenting
            // focus owner moved out if new container prohibit this kind of focus owner.
            if (comp.isFocusOwner() && !comp.canBeFocusOwner()) {
                comp.transferFocus();
            } else if (comp instanceof Container) {
                Component focusOwner = KeyboardFocusManager.getCurrentKeyboardFocusManager().getFocusOwner();
                if (focusOwner != null && isParentOf(focusOwner) && !focusOwner.canBeFocusOwner()) {
                    focusOwner.transferFocus();
                }
            }
        } else {
            comp.createHierarchyEvents(HierarchyEvent.HIERARCHY_CHANGED, comp,
                                       this, HierarchyEvent.HIERARCHY_CHANGED,
                                       Toolkit.enabledOnToolkit(AWTEvent.HIERARCHY_EVENT_MASK));
        }

        if (peer != null && layoutMgr == null && isVisible()) {
            updateCursorImmediately();
        }
    
protected voidaddImpl(java.awt.Component comp, java.lang.Object constraints, int index)
Adds the specified component to this container at the specified index. This method also notifies the layout manager to add the component to this container's layout using the specified constraints object via the addLayoutComponent method.

The constraints are defined by the particular layout manager being used. For example, the BorderLayout class defines five constraints: BorderLayout.NORTH, BorderLayout.SOUTH, BorderLayout.EAST, BorderLayout.WEST, and BorderLayout.CENTER.

The GridBagLayout class requires a GridBagConstraints object. Failure to pass the correct type of constraints object results in an IllegalArgumentException.

If the current layout manager implements {@code LayoutManager2}, then {@link LayoutManager2#addLayoutComponent(Component,Object)} is invoked on it. If the current layout manager does not implement {@code LayoutManager2}, and constraints is a {@code String}, then {@link LayoutManager#addLayoutComponent(String,Component)} is invoked on it.

If the component is not an ancestor of this container and has a non-null parent, it is removed from its current parent before it is added to this container.

This is the method to override if a program needs to track every add request to a container as all other add methods defer to this one. An overriding method should usually include a call to the superclass's version of the method:

super.addImpl(comp, constraints, index)

param
comp the component to be added
param
constraints an object expressing layout constraints for this component
param
index the position in the container's list at which to insert the component, where -1 means append to the end
exception
IllegalArgumentException if {@code index} is invalid; if {@code comp} is a child of this container, the valid range is {@code [-1, getComponentCount()-1]}; if component is not a child of this container, the valid range is {@code [-1, getComponentCount()]}
exception
IllegalArgumentException if {@code comp} is an ancestor of this container
exception
IllegalArgumentException if adding a window to a container
exception
NullPointerException if {@code comp} is {@code null}
see
#add(Component)
see
#add(Component, int)
see
#add(Component, java.lang.Object)
see
LayoutManager
see
LayoutManager2
since
JDK1.1

	synchronized (getTreeLock()) {
	    /* Check for correct arguments:  index in bounds,
	     * comp cannot be one of this container's parents,
	     * and comp cannot be a window.
	     * comp and container must be on the same GraphicsDevice.
	     * if comp is container, all sub-components must be on
	     * same GraphicsDevice.
	     */
	    GraphicsConfiguration thisGC = this.getGraphicsConfiguration();

	    if (index > ncomponents || (index < 0 && index != -1)) {
		throw new IllegalArgumentException(
			  "illegal component position");
	    }
        if (comp instanceof Container) {
            for (Container cn = this; cn != null; cn=cn.parent) {
                if (cn == comp) {
                throw new IllegalArgumentException(
                      "adding container's parent to itself");
                }
            }
            if (comp instanceof Window) {
                throw new IllegalArgumentException(
                       "adding a window to a container");
            }
        }
        if (thisGC != null) {
            comp.checkGD(thisGC.getDevice().getIDstring());
        }

	    /* Reparent the component and tidy up the tree's state. */
	    if (comp.parent != null) {
		comp.parent.remove(comp);
                    if (index > ncomponents) {
                        throw new IllegalArgumentException("illegal component position");
                    }
            }

	    /* Add component to list; allocate new array if necessary. */
	    if (ncomponents == component.length) {
                component = Arrays.copyOf(component, ncomponents * 2 + 1);
	    }
	    if (index == -1 || index == ncomponents) {
		component[ncomponents++] = comp;
	    } else {
		System.arraycopy(component, index, component,
				 index + 1, ncomponents - index);
		component[index] = comp;
		ncomponents++;
	    }
	    comp.parent = this;

	    adjustListeningChildren(AWTEvent.HIERARCHY_EVENT_MASK, 
	        comp.numListening(AWTEvent.HIERARCHY_EVENT_MASK));
	    adjustListeningChildren(AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK,
		comp.numListening(AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK));
            adjustDescendants(comp.countHierarchyMembers());

	    if (valid) {
		invalidate();
	    }
	    if (peer != null) {
		comp.addNotify();
	    }
	    
	    /* Notify the layout manager of the added component. */
	    if (layoutMgr != null) {
		if (layoutMgr instanceof LayoutManager2) {
		    ((LayoutManager2)layoutMgr).addLayoutComponent(comp, constraints);
		} else if (constraints instanceof String) {
		    layoutMgr.addLayoutComponent((String)constraints, comp);
		}
	    }
            if (containerListener != null || 
                (eventMask & AWTEvent.CONTAINER_EVENT_MASK) != 0 ||
                Toolkit.enabledOnToolkit(AWTEvent.CONTAINER_EVENT_MASK)) {
                ContainerEvent e = new ContainerEvent(this, 
                                     ContainerEvent.COMPONENT_ADDED,
                                     comp);
                dispatchEvent(e);
            }

	    comp.createHierarchyEvents(HierarchyEvent.HIERARCHY_CHANGED, comp,
				       this, HierarchyEvent.PARENT_CHANGED,
                                       Toolkit.enabledOnToolkit(AWTEvent.HIERARCHY_EVENT_MASK));
	    if (peer != null && layoutMgr == null && isVisible()) {
                updateCursorImmediately();
	    }
	}
    
public voidaddNotify()
Makes this Container displayable by connecting it to a native screen resource. Making a container displayable will cause all of its children to be made displayable. This method is called internally by the toolkit and should not be called directly by programs.

see
Component#isDisplayable
see
#removeNotify

        synchronized (getTreeLock()) {
	    // addNotify() on the children may cause proxy event enabling
	    // on this instance, so we first call super.addNotify() and
	    // possibly create an lightweight event dispatcher before calling
	    // addNotify() on the children which may be lightweight.
	    super.addNotify();
	    if (! (peer instanceof LightweightPeer)) {
	        dispatcher = new LightweightDispatcher(this);
	    }
	    int ncomponents = this.ncomponents;
            Component component[] = this.component;
	    for (int i = 0 ; i < ncomponents ; i++) {
	        component[i].addNotify();
	    }
            // Update stacking order if native platform allows
            ContainerPeer cpeer = (ContainerPeer)peer;
            if (cpeer.isRestackSupported()) {
                cpeer.restack();
            }


        }
    
public voidaddPropertyChangeListener(java.beans.PropertyChangeListener listener)
Adds a PropertyChangeListener to the listener list. The listener is registered for all bound properties of this class, including the following:
  • this Container's font ("font")
  • this Container's background color ("background")
  • this Container's foreground color ("foreground")
  • this Container's focusability ("focusable")
  • this Container's focus traversal keys enabled state ("focusTraversalKeysEnabled")
  • this Container's Set of FORWARD_TRAVERSAL_KEYS ("forwardFocusTraversalKeys")
  • this Container's Set of BACKWARD_TRAVERSAL_KEYS ("backwardFocusTraversalKeys")
  • this Container's Set of UP_CYCLE_TRAVERSAL_KEYS ("upCycleFocusTraversalKeys")
  • this Container's Set of DOWN_CYCLE_TRAVERSAL_KEYS ("downCycleFocusTraversalKeys")
  • this Container's focus traversal policy ("focusTraversalPolicy")
  • this Container's focus-cycle-root state ("focusCycleRoot")
Note that if this Container is inheriting a bound property, then no event will be fired in response to a change in the inherited property.

If listener is null, no exception is thrown and no action is performed.

param
listener the PropertyChangeListener to be added
see
Component#removePropertyChangeListener
see
#addPropertyChangeListener(java.lang.String,java.beans.PropertyChangeListener)

	super.addPropertyChangeListener(listener);
    
public voidaddPropertyChangeListener(java.lang.String propertyName, java.beans.PropertyChangeListener listener)
Adds a PropertyChangeListener to the listener list for a specific property. The specified property may be user-defined, or one of the following defaults:
  • this Container's font ("font")
  • this Container's background color ("background")
  • this Container's foreground color ("foreground")
  • this Container's focusability ("focusable")
  • this Container's focus traversal keys enabled state ("focusTraversalKeysEnabled")
  • this Container's Set of FORWARD_TRAVERSAL_KEYS ("forwardFocusTraversalKeys")
  • this Container's Set of BACKWARD_TRAVERSAL_KEYS ("backwardFocusTraversalKeys")
  • this Container's Set of UP_CYCLE_TRAVERSAL_KEYS ("upCycleFocusTraversalKeys")
  • this Container's Set of DOWN_CYCLE_TRAVERSAL_KEYS ("downCycleFocusTraversalKeys")
  • this Container's focus traversal policy ("focusTraversalPolicy")
  • this Container's focus-cycle-root state ("focusCycleRoot")
  • this Container's focus-traversal-policy-provider state("focusTraversalPolicyProvider")
  • this Container's focus-traversal-policy-provider state("focusTraversalPolicyProvider")
Note that if this Container is inheriting a bound property, then no event will be fired in response to a change in the inherited property.

If listener is null, no exception is thrown and no action is performed.

param
propertyName one of the property names listed above
param
listener the PropertyChangeListener to be added
see
#addPropertyChangeListener(java.beans.PropertyChangeListener)
see
Component#removePropertyChangeListener

	super.addPropertyChangeListener(propertyName, listener);
    
voidadjustDecendantsOnParent(int num)

        if (parent != null) {
            parent.adjustDescendants(num);
        }
    
voidadjustDescendants(int num)

        if (num == 0) 
            return;

        descendantsCount += num;
        adjustDecendantsOnParent(num);
    
voidadjustListeningChildren(long mask, int num)

        if (dbg.on) {
	    dbg.assertion(mask == AWTEvent.HIERARCHY_EVENT_MASK ||
		       mask == AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK ||
		       mask == (AWTEvent.HIERARCHY_EVENT_MASK |
				AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK));
	}

        if (num == 0)
	    return;

	if ((mask & AWTEvent.HIERARCHY_EVENT_MASK) != 0) {
	    listeningChildren += num;
	}
	if ((mask & AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK) != 0) {
	    listeningBoundsChildren += num;
	}

        adjustListeningChildrenOnParent(mask, num);
    
public voidapplyComponentOrientation(java.awt.ComponentOrientation o)
Sets the ComponentOrientation property of this container and all components contained within it.

param
o the new component orientation of this container and the components contained within it.
exception
NullPointerException if orientation is null.
see
Component#setComponentOrientation
see
Component#getComponentOrientation
since
1.4

        super.applyComponentOrientation(o);
        
        for (int i = 0 ; i < ncomponents ; ++i) {
             component[i].applyComponentOrientation(o);
        }
    
public booleanareFocusTraversalKeysSet(int id)
Returns whether the Set of focus traversal keys for the given focus traversal operation has been explicitly defined for this Container. If this method returns false, this Container is inheriting the Set from an ancestor, or from the current KeyboardFocusManager.

param
id one of KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS, or KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS
return
true if the the Set of focus traversal keys for the given focus traversal operation has been explicitly defined for this Component; false otherwise.
throws
IllegalArgumentException if id is not one of KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS, or KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS
since
1.4

        if (id < 0 || id >= KeyboardFocusManager.TRAVERSAL_KEY_LENGTH) {
	    throw new IllegalArgumentException("invalid focus traversal key identifier");
	}
 
	return (focusTraversalKeys != null && focusTraversalKeys[id] != null);
    
booleancanContainFocusOwner(java.awt.Component focusOwnerCandidate)
Checks whether this container can contain component which is focus owner. Verifies that container is enable and showing, and if it is focus cycle root its FTP allows component to be focus owner

since
1.5

        if (!(isEnabled() && isDisplayable() 
              && isVisible() && isFocusable()))
        {
            return false;
        }
        if (isFocusCycleRoot()) {
            FocusTraversalPolicy policy = getFocusTraversalPolicy();            
            if (policy instanceof DefaultFocusTraversalPolicy) {
                if (!((DefaultFocusTraversalPolicy)policy).accept(focusOwnerCandidate)) {
                    return false;
                }
            }
        }
        synchronized(getTreeLock()) {        
            if (parent != null) {
                return parent.canContainFocusOwner(focusOwnerCandidate);
            }
        }        
        return true;
    
private voidcheckAdding(java.awt.Component comp, int index)
Checks that the component comp can be added to this container Checks : index in bounds of container's size, comp is not one of this container's parents, and comp is not a window. Comp and container must be on the same GraphicsDevice. if comp is container, all sub-components must be on same GraphicsDevice.

since
1.5

        checkTreeLock();

        GraphicsConfiguration thisGC = getGraphicsConfiguration();

        if (index > ncomponents || index < 0) {
            throw new IllegalArgumentException("illegal component position");
        }
        if (comp.parent == this) {
            if (index == ncomponents) {
                throw new IllegalArgumentException("illegal component position " + 
                                                   index + " should be less then " + ncomponents);
            }
        }
        if (comp instanceof Container) {
            for (Container cn = this; cn != null; cn=cn.parent) {
                if (cn == comp) {
                    throw new IllegalArgumentException("adding container's parent to itself");
                }
            }

            if (comp instanceof Window) {
                throw new IllegalArgumentException("adding a window to a container");
            }
        }
        Window thisTopLevel = getContainingWindow();
        Window compTopLevel = comp.getContainingWindow();
        if (thisTopLevel != compTopLevel) {
            throw new IllegalArgumentException("component and container should be in the same top-level window");
        }
        if (thisGC != null) {
            comp.checkGD(thisGC.getDevice().getIDstring());
        }
    
voidcheckGD(java.lang.String stringID)
Checks that all Components that this Container contains are on the same GraphicsDevice as this Container. If not, throws an IllegalArgumentException.

        Component tempComp;
        for (int i = 0; i < component.length; i++) {
            tempComp= component[i];
            if (tempComp != null) {
                tempComp.checkGD(stringID);
            }	
        }
    
voidcheckTreeLock()

        if (!Thread.holdsLock(getTreeLock())) {
            throw new IllegalStateException("This function should be called while holding treeLock");
        }
    
voidclearCurrentFocusCycleRootOnHide()

        KeyboardFocusManager kfm = 
            KeyboardFocusManager.getCurrentKeyboardFocusManager();
        Container cont = kfm.getCurrentFocusCycleRoot();

        synchronized (getTreeLock()) {
            while (this != cont && !(cont instanceof Window) && (cont != null)) {
                cont = cont.getParent();
            }
        }

        if (cont == this) {
            kfm.setGlobalCurrentFocusCycleRoot(null);
        }
    
voidclearMostRecentFocusOwnerOnHide()

        Component comp = null;
        Container window = this;

        synchronized (getTreeLock()) {
            while (window != null && !(window instanceof Window)) {
                window = window.getParent();
            }
            if (window != null) {
                comp = KeyboardFocusManager.
                    getMostRecentFocusOwner((Window)window);
                while ((comp != null) && (comp != this) && !(comp instanceof Window)) {
                    comp = comp.getParent();
                }
            }            
        }

        if (comp == this) {
            KeyboardFocusManager.setMostRecentFocusOwner((Window)window, null);
        }

        if (window != null) {
            Window myWindow = (Window)window;
            synchronized(getTreeLock()) {
                // This synchronized should always be the second in a pair (tree lock, KeyboardFocusManager.class)
                synchronized(KeyboardFocusManager.class) {
                    Component storedComp = myWindow.getTemporaryLostComponent();
                    if (isParentOf(storedComp) || storedComp == this) {
                        myWindow.setTemporaryLostComponent(null);
                    }
                }
            }
        }
    
final booleancontainsFocus()

        synchronized (getTreeLock()) {
            Component comp = KeyboardFocusManager.
                getCurrentKeyboardFocusManager().getFocusOwner();
            while (comp != null && !(comp instanceof Window) && comp != this) 
            {
                comp = (Component) comp.getParent();
            }
            return (comp == this);
        }
    
public intcountComponents()

deprecated
As of JDK version 1.1, replaced by getComponentCount().

	return ncomponents;
    
intcountHierarchyMembers()

        if (dbg.on) {
            // Verify descendantsCount is correct
            int sum = 0;
            for (int i = 0; i < ncomponents; i++) {
                sum += component[i].countHierarchyMembers();
            }
            dbg.assertion(descendantsCount == sum);
        }
        return descendantsCount + 1;
    
final voidcreateChildHierarchyEvents(int id, long changeFlags, boolean enabledOnToolkit)

        assert Thread.holdsLock(getTreeLock());
        if (ncomponents == 0) {
            return;
        }
        int listeners = getListenersCount(id, enabledOnToolkit);

        for (int count = listeners, i = 0; count > 0; i++) {
            count -= component[i].createHierarchyEvents(id, this, parent,
                changeFlags, enabledOnToolkit);
        }
    
final intcreateHierarchyEvents(int id, java.awt.Component changed, java.awt.Container changedParent, long changeFlags, boolean enabledOnToolkit)

        assert Thread.holdsLock(getTreeLock());
        int listeners = getListenersCount(id, enabledOnToolkit);

        for (int count = listeners, i = 0; count > 0; i++) {
	    count -= component[i].createHierarchyEvents(id, changed,
                changedParent, changeFlags, enabledOnToolkit);
	}
	return listeners + 
	    super.createHierarchyEvents(id, changed, changedParent,
					changeFlags, enabledOnToolkit);
    
public voiddeliverEvent(java.awt.Event e)

deprecated
As of JDK version 1.1, replaced by dispatchEvent(AWTEvent e)

	Component comp = getComponentAt(e.x, e.y);
	if ((comp != null) && (comp != this)) {
	    e.translate(-comp.x, -comp.y);
	    comp.deliverEvent(e);
	} else {
	    postEvent(e);
	}
    
voiddispatchEventImpl(java.awt.AWTEvent e)

        if ((dispatcher != null) && dispatcher.dispatchEvent(e)) {
            // event was sent to a lightweight component.  The
            // native-produced event sent to the native container
            // must be properly disposed of by the peer, so it 
            // gets forwarded.  If the native host has been removed
            // as a result of the sending the lightweight event, 
            // the peer reference will be null.
            e.consume();
            if (peer != null) {
                peer.handleEvent(e);
            }
            return;
        }

        super.dispatchEventImpl(e);
 
        synchronized (getTreeLock()) {    
            switch (e.getID()) {
              case ComponentEvent.COMPONENT_RESIZED:
                createChildHierarchyEvents(HierarchyEvent.ANCESTOR_RESIZED, 0,
                                           Toolkit.enabledOnToolkit(AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK));
                break;
              case ComponentEvent.COMPONENT_MOVED:
                createChildHierarchyEvents(HierarchyEvent.ANCESTOR_MOVED, 0,
                                       Toolkit.enabledOnToolkit(AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK));
                break;
              default:
                break;
            }
        }
    
voiddispatchEventToSelf(java.awt.AWTEvent e)

	super.dispatchEventImpl(e);
    
public voiddoLayout()
Causes this container to lay out its components. Most programs should not call this method directly, but should invoke the validate method instead.

see
LayoutManager#layoutContainer
see
#setLayout
see
#validate
since
JDK1.1

	layout();
    
booleaneventEnabled(java.awt.AWTEvent e)

        int id = e.getID();

        if (id == ContainerEvent.COMPONENT_ADDED ||
            id == ContainerEvent.COMPONENT_REMOVED) {
            if ((eventMask & AWTEvent.CONTAINER_EVENT_MASK) != 0 ||
                containerListener != null) {
                return true;
            }
            return false;
        }
        return super.eventEnabled(e);
    
public java.awt.ComponentfindComponentAt(int x, int y)
Locates the visible child component that contains the specified position. The top-most child component is returned in the case where there is overlap in the components. If the containing child component is a Container, this method will continue searching for the deepest nested child component. Components which are not visible are ignored during the search.

The findComponentAt method is different from getComponentAt in that getComponentAt only searches the Container's immediate children; if the containing component is a Container, findComponentAt will search that child to find a nested component.

param
x the x coordinate
param
y the y coordinate
return
null if the component does not contain the position. If there is no child component at the requested point and the point is within the bounds of the container the container itself is returned.
see
Component#contains
see
#getComponentAt
since
1.2

	synchronized (getTreeLock()) {
            return findComponentAt(x, y, true);
	}
    
final java.awt.ComponentfindComponentAt(int x, int y, boolean ignoreEnabled)
Private version of findComponentAt which has a controllable behavior. Setting 'ignoreEnabled' to 'false' bypasses disabled Components during the search. This behavior is used by the lightweight cursor support in sun.awt.GlobalCursorManager. The cursor code calls this function directly via native code. The addition of this feature is temporary, pending the adoption of new, public API which exports this feature.

        if (isRecursivelyVisible()){
            return findComponentAtImpl(x, y, ignoreEnabled);
        }
        return null;
    
public java.awt.ComponentfindComponentAt(java.awt.Point p)
Locates the visible child component that contains the specified point. The top-most child component is returned in the case where there is overlap in the components. If the containing child component is a Container, this method will continue searching for the deepest nested child component. Components which are not visible are ignored during the search.

The findComponentAt method is different from getComponentAt in that getComponentAt only searches the Container's immediate children; if the containing component is a Container, findComponentAt will search that child to find a nested component.

param
p the point.
return
null if the component does not contain the position. If there is no child component at the requested point and the point is within the bounds of the container the container itself is returned.
see
Component#contains
see
#getComponentAt
since
1.2

        return findComponentAt(p.x, p.y);
    
final java.awt.ComponentfindComponentAtImpl(int x, int y, boolean ignoreEnabled)

    
        if (!(contains(x, y) && visible && (ignoreEnabled || enabled))) {
 	    return null;
	}
	int ncomponents = this.ncomponents;
	Component component[] = this.component;

	// Two passes: see comment in sun.awt.SunGraphicsCallback
	for (int i = 0 ; i < ncomponents ; i++) {
	    Component comp = component[i];
            if (comp != null &&
		!(comp.peer instanceof LightweightPeer)) {
		if (comp instanceof Container) {
		    comp = ((Container)comp).findComponentAtImpl(x - comp.x,
							     y - comp.y,
                                                             ignoreEnabled);
		} else {
		    comp = comp.locate(x - comp.x, y - comp.y);
		}
		if (comp != null && comp.visible &&
		    (ignoreEnabled || comp.enabled))
		{
		    return comp;
		}
	    }
	}
	for (int i = 0 ; i < ncomponents ; i++) {
	    Component comp = component[i];
            if (comp != null &&
		comp.peer instanceof LightweightPeer) {
		if (comp instanceof Container) {
		    comp = ((Container)comp).findComponentAtImpl(x - comp.x,
							     y - comp.y,
                                                             ignoreEnabled);
		} else {
		    comp = comp.locate(x - comp.x, y - comp.y);
		}
		if (comp != null && comp.visible &&
		    (ignoreEnabled || comp.enabled))
		{
		    return comp;
		}
	    }
	}
	return this;
    
private java.awt.ContainerfindTraversalRoot()

	// I potentially have two roots, myself and my root parent
	// If I am the current root, then use me
	// If none of my parents are roots, then use me
	// If my root parent is the current root, then use my root parent
	// If neither I nor my root parent is the current root, then
	// use my root parent (a guess)
 
	Container currentFocusCycleRoot = KeyboardFocusManager.
	    getCurrentKeyboardFocusManager().getCurrentFocusCycleRoot();
	Container root;
	
	if (currentFocusCycleRoot == this) {
	    root = this;
	} else {
	    root = getFocusCycleRootAncestor();
	    if (root == null) {
		root = this;
	    }
	}

	if (root != currentFocusCycleRoot) {
	    KeyboardFocusManager.getCurrentKeyboardFocusManager().
		setGlobalCurrentFocusCycleRoot(root);
	}
	return root;
    
javax.accessibility.AccessiblegetAccessibleAt(java.awt.Point p)
Returns the Accessible child contained at the local coordinate Point, if one exists. Otherwise returns null.

param
p the point defining the top-left corner of the Accessible, given in the coordinate space of the object's parent
return
the Accessible at the specified location, if it exists; otherwise null

        synchronized (getTreeLock()) {
            if (this instanceof Accessible) {
                Accessible a = (Accessible)this;
                AccessibleContext ac = a.getAccessibleContext();
                if (ac != null) {
                    AccessibleComponent acmp;
                    Point location;
                    int nchildren = ac.getAccessibleChildrenCount();
                    for (int i=0; i < nchildren; i++) {
                        a = ac.getAccessibleChild(i);
                        if ((a != null)) {
                            ac = a.getAccessibleContext();
                            if (ac != null) {
                                acmp = ac.getAccessibleComponent();
                                if ((acmp != null) && (acmp.isShowing())) {
                                    location = acmp.getLocation();
                                    Point np = new Point(p.x-location.x,
                                                         p.y-location.y);
                                    if (acmp.contains(np)){
                                        return a;
                                    }
                                }
                            }
                        }
                    }
                }
                return (Accessible)this;
            } else {
                Component ret = this;
                if (!this.contains(p.x,p.y)) {
                    ret = null;
                } else {
                    int ncomponents = this.getComponentCount();
                    for (int i=0; i < ncomponents; i++) {
                        Component comp = this.getComponent(i);
                        if ((comp != null) && comp.isShowing()) {
                            Point location = comp.getLocation();
                            if (comp.contains(p.x-location.x,p.y-location.y)) {
                                ret = comp;
                            }
                        }
                    }
                }
                if (ret instanceof Accessible) {
                    return (Accessible) ret;
                }
            }
            return null;
        }
    
javax.accessibility.AccessiblegetAccessibleChild(int i)
Returns the nth Accessible child of the object.

param
i zero-based index of child
return
the nth Accessible child of the object

        synchronized (getTreeLock()) {
            Component[] children = this.getComponents();
            int count = 0;
            for (int j = 0; j < children.length; j++) {
                if (children[j] instanceof Accessible) {
                    if (count == i) {
                        return (Accessible) children[j];
                    } else {
                        count++;
                    }
                }
            }
            return null;
        }
    
intgetAccessibleChildrenCount()
Returns the number of accessible children in the object. If all of the children of this object implement Accessible, then this method should return the number of children of this object.

return
the number of accessible children in the object

        synchronized (getTreeLock()) {
            int count = 0;
            Component[] children = this.getComponents();
            for (int i = 0; i < children.length; i++) {
                if (children[i] instanceof Accessible) {
                    count++;
                }
            }
            return count;
        }
    
public floatgetAlignmentX()
Returns the alignment along the x axis. This specifies how the component would like to be aligned relative to other components. The value should be a number between 0 and 1 where 0 represents alignment along the origin, 1 is aligned the furthest away from the origin, 0.5 is centered, etc.

	float xAlign;
	if (layoutMgr instanceof LayoutManager2) {
	    synchronized (getTreeLock()) {
		LayoutManager2 lm = (LayoutManager2) layoutMgr;
		xAlign = lm.getLayoutAlignmentX(this);
	    }
	} else {
	    xAlign = super.getAlignmentX();
	}
	return xAlign;
    
public floatgetAlignmentY()
Returns the alignment along the y axis. This specifies how the component would like to be aligned relative to other components. The value should be a number between 0 and 1 where 0 represents alignment along the origin, 1 is aligned the furthest away from the origin, 0.5 is centered, etc.

	float yAlign;
	if (layoutMgr instanceof LayoutManager2) {
	    synchronized (getTreeLock()) {
		LayoutManager2 lm = (LayoutManager2) layoutMgr;
		yAlign = lm.getLayoutAlignmentY(this);
	    }
	} else {
	    yAlign = super.getAlignmentY();
	}
	return yAlign;
    
public java.awt.ComponentgetComponent(int n)
Gets the nth component in this container.

param
n the index of the component to get.
return
the nth component in this container.
exception
ArrayIndexOutOfBoundsException if the nth value does not exist.

	synchronized (getTreeLock()) {
	    if ((n < 0) || (n >= ncomponents)) {
		throw new ArrayIndexOutOfBoundsException("No such child: " + n);
	    }
	    return component[n];
	}
    
public java.awt.ComponentgetComponentAt(int x, int y)
Locates the component that contains the x,y position. The top-most child component is returned in the case where there is overlap in the components. This is determined by finding the component closest to the index 0 that claims to contain the given point via Component.contains(), except that Components which have native peers take precedence over those which do not (i.e., lightweight Components).

param
x the x coordinate
param
y the y coordinate
return
null if the component does not contain the position. If there is no child component at the requested point and the point is within the bounds of the container the container itself is returned; otherwise the top-most child is returned.
see
Component#contains
since
JDK1.1

        return locate(x, y);
    
public java.awt.ComponentgetComponentAt(java.awt.Point p)
Gets the component that contains the specified point.

param
p the point.
return
returns the component that contains the point, or null if the component does not contain the point.
see
Component#contains
since
JDK1.1

	return getComponentAt(p.x, p.y);
    
public intgetComponentCount()
Gets the number of components in this panel.

return
the number of components in this panel.
see
#getComponent
since
JDK1.1

	return countComponents();
    
public intgetComponentZOrder(java.awt.Component comp)
Returns the z-order index of the component inside the container. The higher a component is in the z-order hierarchy, the lower its index. The component with the lowest z-order index is painted last, above all other child components.

param
comp the component being queried
return
the z-order index of the component; otherwise returns -1 if the component is null or doesn't belong to the container
see
#setComponentZOrder(java.awt.Component, int)
since
1.5

        if (comp == null) {
            return -1;
        }
        synchronized(getTreeLock()) {
            // Quick check - container should be immediate parent of the component
            if (comp.parent != this) {
                return -1;
            }
            for (int i = 0; i < ncomponents; i++) {
                if (component[i] == comp) {
                    return i;
                }
            }            
        }
        // To please javac
        return -1;
    
public java.awt.Component[]getComponents()
Gets all the components in this container.

return
an array of all the components in this container.

	return getComponents_NoClientCode();
    
final java.awt.Component[]getComponents_NoClientCode()

	synchronized (getTreeLock()) {
            return Arrays.copyOf(component, ncomponents);
	}
    
public synchronized java.awt.event.ContainerListener[]getContainerListeners()
Returns an array of all the container listeners registered on this container.

return
all of this container's ContainerListeners or an empty array if no container listeners are currently registered
see
#addContainerListener
see
#removeContainerListener
since
1.4

        return (ContainerListener[]) (getListeners(ContainerListener.class));
    
java.awt.ComponentgetDropTargetEventTarget(int x, int y, boolean includeSelf)
Fetches the top-most (deepest) component to receive SunDropTargetEvents.

        return getMouseEventTarget(x, y, includeSelf, 
                                   DropTargetEventTargetFilter.FILTER, 
                                   SEARCH_HEAVYWEIGHTS);
    
public java.util.SetgetFocusTraversalKeys(int id)
Returns the Set of focus traversal keys for a given traversal operation for this Container. (See setFocusTraversalKeys for a full description of each key.)

If a Set of traversal keys has not been explicitly defined for this Container, then this Container's parent's Set is returned. If no Set has been explicitly defined for any of this Container's ancestors, then the current KeyboardFocusManager's default Set is returned.

param
id one of KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS, or KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS
return
the Set of AWTKeyStrokes for the specified operation. The Set will be unmodifiable, and may be empty. null will never be returned.
see
#setFocusTraversalKeys
see
KeyboardFocusManager#FORWARD_TRAVERSAL_KEYS
see
KeyboardFocusManager#BACKWARD_TRAVERSAL_KEYS
see
KeyboardFocusManager#UP_CYCLE_TRAVERSAL_KEYS
see
KeyboardFocusManager#DOWN_CYCLE_TRAVERSAL_KEYS
throws
IllegalArgumentException if id is not one of KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS, or KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS
since
1.4

        if (id < 0 || id >= KeyboardFocusManager.TRAVERSAL_KEY_LENGTH) {
	    throw new IllegalArgumentException("invalid focus traversal key identifier");
	}
 
	// Don't call super.getFocusTraversalKey. The Component parameter check
	// does not allow DOWN_CYCLE_TRAVERSAL_KEY, but we do.
	return getFocusTraversalKeys_NoIDCheck(id);
    
public java.awt.FocusTraversalPolicygetFocusTraversalPolicy()
Returns the focus traversal policy that will manage keyboard traversal of this Container's children, or null if this Container is not a focus cycle root. If no traversal policy has been explicitly set for this Container, then this Container's focus-cycle-root ancestor's policy is returned.

return
this Container's focus traversal policy, or null if this Container is not a focus cycle root.
see
#setFocusTraversalPolicy
see
#setFocusCycleRoot
see
#isFocusCycleRoot
since
1.4

        if (!isFocusTraversalPolicyProvider() && !isFocusCycleRoot()) {
	    return null;
	}
 
	FocusTraversalPolicy policy = this.focusTraversalPolicy;
	if (policy != null) {
	    return policy;
	}
 
	Container rootAncestor = getFocusCycleRootAncestor();
	if (rootAncestor != null) {
	    return rootAncestor.getFocusTraversalPolicy();
	} else {
	    return KeyboardFocusManager.getCurrentKeyboardFocusManager().
	        getDefaultFocusTraversalPolicy();
	}
    
java.awt.ContainergetHeavyweightContainer()
Returns closest heavyweight component to this container. If this container is heavyweight returns this.

since
1.5

        checkTreeLock();
        if (peer != null && !(peer instanceof LightweightPeer)) {
            return this;
        } else {
            return getNativeContainer();
        }
    
public java.awt.InsetsgetInsets()
Determines the insets of this container, which indicate the size of the container's border.

A Frame object, for example, has a top inset that corresponds to the height of the frame's title bar.

return
the insets of this container.
see
Insets
see
LayoutManager
since
JDK1.1

    	return insets();
    
public java.awt.LayoutManagergetLayout()
Gets the layout manager for this container.

see
#doLayout
see
#setLayout

	return layoutMgr;
    
public T[]getListeners(java.lang.Class listenerType)
Returns an array of all the objects currently registered as FooListeners upon this Container. FooListeners are registered using the addFooListener method.

You can specify the listenerType argument with a class literal, such as FooListener.class. For example, you can query a Container c for its container listeners with the following code:

ContainerListener[] cls = (ContainerListener[])(c.getListeners(ContainerListener.class));
If no such listeners exist, this method returns an empty array.

param
listenerType the type of listeners requested; this parameter should specify an interface that descends from java.util.EventListener
return
an array of all objects registered as FooListeners on this container, or an empty array if no such listeners have been added
exception
ClassCastException if listenerType doesn't specify a class or interface that implements java.util.EventListener
see
#getContainerListeners
since
1.3

 
	EventListener l = null; 
	if  (listenerType == ContainerListener.class) { 
	    l = containerListener;
	} else {
	    return super.getListeners(listenerType);
	}
	return AWTEventMulticaster.getListeners(l, listenerType);
    
private intgetListenersCount(int id, boolean enabledOnToolkit)

    	assert Thread.holdsLock(getTreeLock());
        if (enabledOnToolkit) {
            return descendantsCount;
        }
	switch (id) {
	  case HierarchyEvent.HIERARCHY_CHANGED:
            return listeningChildren;
	  case HierarchyEvent.ANCESTOR_MOVED:
	  case HierarchyEvent.ANCESTOR_RESIZED:
            return listeningBoundsChildren;
	  default:
            return 0;
        }
    
public java.awt.DimensiongetMaximumSize()
Returns the maximum size of this container. If the maximum size has not been set explicitly by {@link Component#setMaximumSize(Dimension)} and the {@link LayoutManager} installed on this {@code Container} is an instance of {@link LayoutManager2}, then {@link LayoutManager2#maximumLayoutSize(Container)} is used to calculate the maximum size.

Note: some implementations may cache the value returned from the {@code LayoutManager2}. Implementations that cache need not invoke {@code maximumLayoutSize} on the {@code LayoutManager2} every time this method is invoked, rather the {@code LayoutManager2} will only be queried after the {@code Container} becomes invalid.

return
an instance of Dimension that represents the maximum size of this container.
see
#getPreferredSize
see
#getMinimumSize
see
#getLayout
see
LayoutManager2#maximumLayoutSize(Container)
see
Component#getMaximumSize

	/* Avoid grabbing the lock if a reasonable cached size value
	 * is available.
	 */ 
    	Dimension dim = maxSize;
    	if (dim == null || !(isMaximumSizeSet() || isValid())) {
	    synchronized (getTreeLock()) {
               if (layoutMgr instanceof LayoutManager2) {
                    LayoutManager2 lm = (LayoutManager2) layoutMgr;
                    maxSize = lm.maximumLayoutSize(this);
               } else {
                    maxSize = super.getMaximumSize();
               }
               dim = maxSize;
            }
	}
        if (dim != null){
            return new Dimension(dim);
        }
        else{
            return dim;
        }
    
public java.awt.DimensiongetMinimumSize()
Returns the minimum size of this container. If the minimum size has not been set explicitly by {@link Component#setMinimumSize(Dimension)} and this {@code Container} has a {@code non-null} {@link LayoutManager}, then {@link LayoutManager#minimumLayoutSize(Container)} is used to calculate the minimum size.

Note: some implementations may cache the value returned from the {@code LayoutManager}. Implementations that cache need not invoke {@code minimumLayoutSize} on the {@code LayoutManager} every time this method is invoked, rather the {@code LayoutManager} will only be queried after the {@code Container} becomes invalid.

return
an instance of Dimension that represents the minimum size of this container.
see
#getPreferredSize
see
#getMaximumSize
see
#getLayout
see
LayoutManager#minimumLayoutSize(Container)
see
Component#getMinimumSize
since
JDK1.1

	return minimumSize();
    
java.awt.ComponentgetMouseEventTarget(int x, int y, boolean includeSelf)
Fetchs the top-most (deepest) lightweight component that is interested in receiving mouse events.

        return getMouseEventTarget(x, y, includeSelf, 
                                   MouseEventTargetFilter.FILTER, 
                                   !SEARCH_HEAVYWEIGHTS);
    
private java.awt.ComponentgetMouseEventTarget(int x, int y, boolean includeSelf, java.awt.Container$EventTargetFilter filter, boolean searchHeavyweights)
A private version of getMouseEventTarget which has two additional controllable behaviors. This method searches for the top-most descendant of this container that contains the given coordinates and is accepted by the given filter. The search will be constrained to lightweight descendants if the last argument is false.

param
filter EventTargetFilter instance to determine whether the given component is a valid target for this event.
param
searchHeavyweights if false, the method will bypass heavyweight components during the search.

        Component comp = null;
        if (searchHeavyweights) {
            comp = getMouseEventTargetImpl(x, y, includeSelf, filter,
                                           SEARCH_HEAVYWEIGHTS,
                                           searchHeavyweights);
        }
        
        if (comp == null || comp == this) {
            comp = getMouseEventTargetImpl(x, y, includeSelf, filter,
                                           !SEARCH_HEAVYWEIGHTS,
                                           searchHeavyweights);            
        }

        return comp;
    
private java.awt.ComponentgetMouseEventTargetImpl(int x, int y, boolean includeSelf, java.awt.Container$EventTargetFilter filter, boolean searchHeavyweightChildren, boolean searchHeavyweightDescendants)
A private version of getMouseEventTarget which has three additional controllable behaviors. This method searches for the top-most descendant of this container that contains the given coordinates and is accepted by the given filter. The search will be constrained to descendants of only lightweight children or only heavyweight children of this container depending on searchHeavyweightChildren. The search will be constrained to only lightweight descendants of the searched children of this container if searchHeavyweightDescendants is false.

param
filter EventTargetFilter instance to determine whether the selected component is a valid target for this event.
param
searchHeavyweightChildren if true, the method will bypass immediate lightweight children during the search. If false, the methods will bypass immediate heavyweight children during the search.
param
searchHeavyweightDescendants if false, the method will bypass heavyweight descendants which are not immediate children during the search. If true, the method will traverse both lightweight and heavyweight descendants during the search.

        int ncomponents = this.ncomponents;
        Component component[] = this.component;

        for (int i = 0 ; i < ncomponents ; i++) {
            Component comp = component[i];
            if (comp != null && comp.visible &&
                ((!searchHeavyweightChildren && 
                  comp.peer instanceof LightweightPeer) ||
                 (searchHeavyweightChildren &&
                  !(comp.peer instanceof LightweightPeer))) &&
                comp.contains(x - comp.x, y - comp.y)) {

                // found a component that intersects the point, see if there is 
                // a deeper possibility.
                if (comp instanceof Container) {
                    Container child = (Container) comp;
		    Component deeper = child.getMouseEventTarget(x - child.x,
                                                                 y - child.y,
                                                                 includeSelf,
                                                                 filter,
                                                                 searchHeavyweightDescendants);
                    if (deeper != null) {
                        return deeper;
                    }
                } else {
                    if (filter.accept(comp)) {
                        // there isn't a deeper target, but this component is a
                        // target
                        return comp;
                    }
                }
            }
        }
	
        boolean isPeerOK;
        boolean	isMouseOverMe;
	
        isPeerOK = (peer instanceof LightweightPeer) || includeSelf;
        isMouseOverMe = contains(x,y);

        // didn't find a child target, return this component if it's a possible
        // target
        if (isMouseOverMe && isPeerOK && filter.accept(this)) {
            return this;
        }
        // no possible target
        return null;
    
public java.awt.PointgetMousePosition(boolean allowChildren)
Returns the position of the mouse pointer in this Container's coordinate space if the Container is under the mouse pointer, otherwise returns null. This method is similar to {@link Component#getMousePosition()} with the exception that it can take the Container's children into account. If allowChildren is false, this method will return a non-null value only if the mouse pointer is above the Container directly, not above the part obscured by children. If allowChildren is true, this method returns a non-null value if the mouse pointer is above Container or any of its descendants.

exception
HeadlessException if GraphicsEnvironment.isHeadless() returns true
param
allowChildren true if children should be taken into account
see
Component#getMousePosition
return
mouse coordinates relative to this Component, or null
since
1.5

        if (GraphicsEnvironment.isHeadless()) {
            throw new HeadlessException();
        }
        PointerInfo pi = (PointerInfo)java.security.AccessController.doPrivileged(
            new java.security.PrivilegedAction() {
                public Object run() {
                    return MouseInfo.getPointerInfo();
                }
            }
        );
        synchronized (getTreeLock()) {
            Component inTheSameWindow = findUnderMouseInWindow(pi);
            if (isSameOrAncestorOf(inTheSameWindow, allowChildren)) {
                return  pointRelativeToComponent(pi.getLocation());
            }
            return null;
        }
    
public java.awt.DimensiongetPreferredSize()
Returns the preferred size of this container. If the preferred size has not been set explicitly by {@link Component#setPreferredSize(Dimension)} and this {@code Container} has a {@code non-null} {@link LayoutManager}, then {@link LayoutManager#preferredLayoutSize(Container)} is used to calculate the preferred size.

Note: some implementations may cache the value returned from the {@code LayoutManager}. Implementations that cache need not invoke {@code preferredLayoutSize} on the {@code LayoutManager} every time this method is invoked, rather the {@code LayoutManager} will only be queried after the {@code Container} becomes invalid.

return
an instance of Dimension that represents the preferred size of this container.
see
#getMinimumSize
see
#getMaximumSize
see
#getLayout
see
LayoutManager#preferredLayoutSize(Container)
see
Component#getPreferredSize

	return preferredSize();
    
private booleanhasHeavyweightChildren()
Checks whether or not this container has heavyweight children. Note: Should be called while holding tree lock

return
true if there is at least one heavyweight children in a container, false otherwise
since
1.5

        
        checkTreeLock();
        boolean res = true; // true while it is lightweight
        for (int i = 0; i < getComponentCount() && res; i++) {
            Component child = getComponent(i);
            res &= child.isLightweight();
            if (res && child instanceof Container) {
                res &= !((Container)child).hasHeavyweightChildren();
            }
        }
        return !res;
    
private static native voidinitIDs()
Initialize JNI field and method IDs for fields that may be called from C.

voidinitializeFocusTraversalKeys()

	focusTraversalKeys = new Set[4];
    
public java.awt.Insetsinsets()

deprecated
As of JDK version 1.1, replaced by getInsets().

        ComponentPeer peer = this.peer;
	if (peer instanceof ContainerPeer) {
	    ContainerPeer cpeer = (ContainerPeer)peer;
	    return (Insets)cpeer.insets().clone();
	}
	return new Insets(0, 0, 0, 0);
    
public voidinvalidate()
Invalidates the container. The container and all parents above it are marked as needing to be laid out. This method can be called often, so it needs to execute quickly.

If the {@code LayoutManager} installed on this container is an instance of {@code LayoutManager2}, then {@link LayoutManager2#invalidateLayout(Container)} is invoked on it supplying this {@code Container} as the argument.

see
#validate
see
#layout
see
LayoutManager
see
LayoutManager2#invalidateLayout(Container)

        LayoutManager layoutMgr = this.layoutMgr;
	if (layoutMgr instanceof LayoutManager2) {
	    LayoutManager2 lm = (LayoutManager2) layoutMgr;
	    lm.invalidateLayout(this);
	}
	super.invalidate();
    
voidinvalidateTree()
Recursively descends the container tree and invalidates all contained components.

        synchronized (getTreeLock()) {
	    for (int i = 0; i < ncomponents; ++i) {
	        Component comp = component[i];
		if (comp instanceof Container) {
		    ((Container)comp).invalidateTree();
		}
		else {
		    if (comp.valid) {
		        comp.invalidate();
		    }
		}
	    }
	    if (valid) {
	        invalidate();
	    }
	}
    
public booleanisAncestorOf(java.awt.Component c)
Checks if the component is contained in the component hierarchy of this container.

param
c the component
return
true if it is an ancestor; false otherwise.
since
JDK1.1

	Container p;
	if (c == null || ((p = c.getParent()) == null)) {
	    return false;
	}
	while (p != null) {
	    if (p == this) {
		return true;
	    }
	    p = p.getParent();
	}
	return false;
    
public booleanisFocusCycleRoot(java.awt.Container container)
Returns whether the specified Container is the focus cycle root of this Container's focus traversal cycle. Each focus traversal cycle has only a single focus cycle root and each Container which is not a focus cycle root belongs to only a single focus traversal cycle. Containers which are focus cycle roots belong to two cycles: one rooted at the Container itself, and one rooted at the Container's nearest focus-cycle-root ancestor. This method will return true for both such Containers in this case.

param
container the Container to be tested
return
true if the specified Container is a focus-cycle- root of this Container; false otherwise
see
#isFocusCycleRoot()
since
1.4

        if (isFocusCycleRoot() && container == this) {
	    return true;
	} else {
	    return super.isFocusCycleRoot(container);
	}
    
public booleanisFocusCycleRoot()
Returns whether this Container is the root of a focus traversal cycle. Once focus enters a traversal cycle, typically it cannot leave it via focus traversal unless one of the up- or down-cycle keys is pressed. Normal traversal is limited to this Container, and all of this Container's descendants that are not descendants of inferior focus cycle roots. Note that a FocusTraversalPolicy may bend these restrictions, however. For example, ContainerOrderFocusTraversalPolicy supports implicit down-cycle traversal.

return
whether this Container is the root of a focus traversal cycle
see
#setFocusCycleRoot
see
#setFocusTraversalPolicy
see
#getFocusTraversalPolicy
see
ContainerOrderFocusTraversalPolicy
since
1.4

        return focusCycleRoot;
    
public final booleanisFocusTraversalPolicyProvider()
Returns whether this container provides focus traversal policy. If this property is set to true then when keyboard focus manager searches container hierarchy for focus traversal policy and encounters this container before any other container with this property as true or focus cycle roots then its focus traversal policy will be used instead of focus cycle root's policy.

see
#setFocusTraversalPolicy
see
#getFocusTraversalPolicy
see
#setFocusCycleRoot
see
#setFocusTraversalPolicyProvider
return
true if this container provides focus traversal policy, false otherwise
since
1.5
beaninfo
bound: true

        return focusTraversalPolicyProvider;
    
public booleanisFocusTraversalPolicySet()
Returns whether the focus traversal policy has been explicitly set for this Container. If this method returns false, this Container will inherit its focus traversal policy from an ancestor.

return
true if the focus traversal policy has been explicitly set for this Container; false otherwise.
since
1.4

        return (focusTraversalPolicy != null);
    
booleanisParentOf(java.awt.Component comp)
Check if this component is the child of this container or its children. Note: this function acquires treeLock Note: this function traverses children tree only in one Window.

param
comp a component in test, must not be null

        synchronized(getTreeLock()) {
            while (comp != null && comp != this && !(comp instanceof Window)) {
                comp = comp.getParent();
            }
            return (comp == this);
        }
    
private static booleanisRemoveNotifyNeeded(java.awt.Component comp, java.awt.Container oldContainer, java.awt.Container newContainer)
Detects whether or not remove from current parent and adding to new parent requires call of removeNotify on the component. Since removeNotify destroys native window this might (not) be required. For example, if new container and old containers are the same we don't need to destroy native window.

since:
1.5

        if (oldContainer == null) { // Component didn't have parent - no removeNotify
            return false;
        }
        if (comp.peer == null) { // Component didn't have peer - no removeNotify
            return false;
        }
        if (newContainer.peer == null) {
            // Component has peer but new Container doesn't - call removeNotify
            return true;
        }

        // If component is lightweight non-Container or lightweight Container with all but heavyweight
        // children there is no need to call remove notify
        if (comp.isLightweight()) {
            if (comp instanceof Container) {
                // If it has heavyweight children then removeNotify is required
                return ((Container)comp).hasHeavyweightChildren();
            } else {
                // Just a lightweight
                return false;
            }
        }

        // All three components have peers, check for peer change
        Container newNativeContainer = oldContainer.getHeavyweightContainer();
        Container oldNativeContainer = newContainer.getHeavyweightContainer();
        if (newNativeContainer != oldNativeContainer) {
            // Native containers change - check whether or not current platform supports
            // changing of widget hierarchy on native level without recreation.
            return !comp.peer.isReparentSupported();
        } else {
            // if container didn't change we still might need to recreate component's window as
            // changes to zorder should be reflected in native window stacking order and it might
            // not be supported by the platform. This is important only for heavyweight child
            return !comp.isLightweight() && 
                !((ContainerPeer)(newNativeContainer.peer)).isRestackSupported();
        }
    
booleanisSameOrAncestorOf(java.awt.Component comp, boolean allowChildren)

        return this == comp || (allowChildren && isParentOf(comp));
    
public voidlayout()

deprecated
As of JDK version 1.1, replaced by doLayout().

	LayoutManager layoutMgr = this.layoutMgr;
	if (layoutMgr != null) {
	    layoutMgr.layoutContainer(this);
	}
    
voidlightweightPaint(java.awt.Graphics g)
Simulates the peer callbacks into java.awt for printing of lightweight Containers.

param
g the graphics context to use for printing.
see
Component#printAll
see
#printComponents

        super.lightweightPaint(g);
        paintHeavyweightComponents(g);
    
voidlightweightPrint(java.awt.Graphics g)
Simulates the peer callbacks into java.awt for printing of lightweight Containers.

param
g the graphics context to use for printing.
see
Component#printAll
see
#printComponents

        super.lightweightPrint(g);
        printHeavyweightComponents(g);
    
public voidlist(java.io.PrintStream out, int indent)
Prints a listing of this container to the specified output stream. The listing starts at the specified indentation.

The immediate children of the container are printed with an indentation of indent+1. The children of those children are printed at indent+2 and so on.

param
out a print stream
param
indent the number of spaces to indent
see
Component#list(java.io.PrintStream, int)
since
JDK1.0

	super.list(out, indent);
	int ncomponents = this.ncomponents;
        Component component[] = this.component;
	for (int i = 0 ; i < ncomponents ; i++) {
	    Component comp = component[i];
	    if (comp != null) {
		comp.list(out, indent+1);
	    }
	}
    
public voidlist(java.io.PrintWriter out, int indent)
Prints out a list, starting at the specified indentation, to the specified print writer.

The immediate children of the container are printed with an indentation of indent+1. The children of those children are printed at indent+2 and so on.

param
out a print writer
param
indent the number of spaces to indent
see
Component#list(java.io.PrintWriter, int)
since
JDK1.1

	super.list(out, indent);
	int ncomponents = this.ncomponents;
        Component component[] = this.component;
	for (int i = 0 ; i < ncomponents ; i++) {
	    Component comp = component[i];
	    if (comp != null) {
		comp.list(out, indent+1);
	    }
	}
    
public java.awt.Componentlocate(int x, int y)

deprecated
As of JDK version 1.1, replaced by getComponentAt(int, int).

	if (!contains(x, y)) {
	    return null;
	}
	synchronized (getTreeLock()) {
	    // Two passes: see comment in sun.awt.SunGraphicsCallback
	    for (int i = 0 ; i < ncomponents ; i++) {
	        Component comp = component[i];
		if (comp != null &&
		    !(comp.peer instanceof LightweightPeer)) {
		    if (comp.contains(x - comp.x, y - comp.y)) {
		        return comp;
		    }
		}
	    }
	    for (int i = 0 ; i < ncomponents ; i++) {
	        Component comp = component[i];
		if (comp != null &&
		    comp.peer instanceof LightweightPeer) {
		    if (comp.contains(x - comp.x, y - comp.y)) {
		        return comp;
		    }
		}
	    }
	}
	return this;
    
public java.awt.DimensionminimumSize()

deprecated
As of JDK version 1.1, replaced by getMinimumSize().

	/* Avoid grabbing the lock if a reasonable cached size value
	 * is available.
	 */ 
    	Dimension dim = minSize;
    	if (dim == null || !(isMinimumSizeSet() || isValid())) {
	    synchronized (getTreeLock()) {
		minSize = (layoutMgr != null) ?
		    layoutMgr.minimumLayoutSize(this) :
		    super.minimumSize();
                dim = minSize;
	    }
	}
        if (dim != null){
            return new Dimension(dim);
        }
        else{
            return dim;
        }
    
booleannextFocusHelper()

        if (isFocusCycleRoot()) {
            Container root = findTraversalRoot();
            Component comp = this;
            Container anc;
            while (root != null && 
                   (anc = root.getFocusCycleRootAncestor()) != null &&
                   !(root.isShowing() && 
                     root.isFocusable() && 
                     root.isEnabled())) 
            {
                comp = root;
                root = anc;
            }
            if (root != null) {
                FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
                Component toFocus = policy.getComponentAfter(root, comp);
                if (toFocus == null) {
                    toFocus = policy.getDefaultComponent(root);
                }
                if (toFocus != null) {
                    return toFocus.requestFocus(false, CausedFocusEvent.Cause.TRAVERSAL_FORWARD);
                }
            }
            return false;
        } else {
            // I only have one root, so the general case will suffice
            return super.nextFocusHelper();
        }
    
intnumListening(long mask)

        int superListening = super.numListening(mask);

        if (mask == AWTEvent.HIERARCHY_EVENT_MASK) {
	    if (dbg.on) {
	        // Verify listeningChildren is correct
	        int sum = 0;
		for (int i = 0; i < ncomponents; i++) {
		    sum += component[i].numListening(mask);
		}
		dbg.assertion(listeningChildren == sum);
	    }
	    return listeningChildren + superListening;
	} else if (mask == AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK) {
	    if (dbg.on) {
	        // Verify listeningBoundsChildren is correct
	        int sum = 0;
		for (int i = 0; i < ncomponents; i++) {
		    sum += component[i].numListening(mask);
		}
		dbg.assertion(listeningBoundsChildren == sum);
	    }
	    return listeningBoundsChildren + superListening;
	} else {
	    if (dbg.on) {
	        dbg.assertion(false);
	    }
	    return superListening;
	}
    
public voidpaint(java.awt.Graphics g)
Paints the container. This forwards the paint to any lightweight components that are children of this container. If this method is reimplemented, super.paint(g) should be called so that lightweight components are properly rendered. If a child component is entirely clipped by the current clipping setting in g, paint() will not be forwarded to that child.

param
g the specified Graphics window
see
Component#update(Graphics)

	if (isShowing()) {
	    if (printing) {
	        synchronized (this) {
		    if (printing) {
		        if (printingThreads.contains(Thread.currentThread())) {
			    return;
			}
		    }
		}
	    }

	    // The container is showing on screen and
	    // this paint() is not called from print().
	    // Paint self and forward the paint to lightweight subcomponents.

	    // super.paint(); -- Don't bother, since it's a NOP.

	    GraphicsCallback.PaintCallback.getInstance().
	        runComponents(component, g, GraphicsCallback.LIGHTWEIGHTS);
	}
    
public voidpaintComponents(java.awt.Graphics g)
Paints each of the components in this container.

param
g the graphics context.
see
Component#paint
see
Component#paintAll

        if (isShowing()) {
	    GraphicsCallback.PaintAllCallback.getInstance().
	        runComponents(component, g, GraphicsCallback.TWO_PASSES);
	}
    
voidpaintHeavyweightComponents(java.awt.Graphics g)
Prints all the heavyweight subcomponents.

        if (isShowing()) {
	    GraphicsCallback.PaintHeavyweightComponentsCallback.getInstance().
	        runComponents(component, g, GraphicsCallback.LIGHTWEIGHTS |
                                            GraphicsCallback.HEAVYWEIGHTS);
	}
    
protected java.lang.StringparamString()
Returns a string representing the state of this Container. This method is intended to be used only for debugging purposes, and the content and format of the returned string may vary between implementations. The returned string may be empty but may not be null.

return
the parameter string of this container

	String str = super.paramString();
	LayoutManager layoutMgr = this.layoutMgr;
	if (layoutMgr != null) {
	    str += ",layout=" + layoutMgr.getClass().getName();
	}
	return str;
    
voidpostProcessKeyEvent(java.awt.event.KeyEvent e)

        Container parent = this.parent;
        if (parent != null) {
            parent.postProcessKeyEvent(e);
        }
    
booleanpostsOldMouseEvents()

        return true;
    
voidpreProcessKeyEvent(java.awt.event.KeyEvent e)

        Container parent = this.parent;
        if (parent != null) {
            parent.preProcessKeyEvent(e);
        }
    
public java.awt.DimensionpreferredSize()

deprecated
As of JDK version 1.1, replaced by getPreferredSize().

	/* Avoid grabbing the lock if a reasonable cached size value
	 * is available.
	 */ 
    	Dimension dim = prefSize;
    	if (dim == null || !(isPreferredSizeSet() || isValid())) {
	    synchronized (getTreeLock()) {
		prefSize = (layoutMgr != null) ?
		    layoutMgr.preferredLayoutSize(this) :
		    super.preferredSize();
                dim = prefSize;
            }
	}
        if (dim != null){
            return new Dimension(dim);
        }
        else{
            return dim;
        }
    
public voidprint(java.awt.Graphics g)
Prints the container. This forwards the print to any lightweight components that are children of this container. If this method is reimplemented, super.print(g) should be called so that lightweight components are properly rendered. If a child component is entirely clipped by the current clipping setting in g, print() will not be forwarded to that child.

param
g the specified Graphics window
see
Component#update(Graphics)

        if (isShowing()) {
	    Thread t = Thread.currentThread();
	    try {
	        synchronized (this) {
		    if (printingThreads == null) {
		        printingThreads = new HashSet();
		    }
		    printingThreads.add(t);
		    printing = true;
		}
		super.print(g);  // By default, Component.print() calls paint()
	    } finally {
	        synchronized (this) {
		    printingThreads.remove(t);
		    printing = !printingThreads.isEmpty();
		}
	    }

	    GraphicsCallback.PrintCallback.getInstance().
	        runComponents(component, g, GraphicsCallback.LIGHTWEIGHTS);
	}
    
public voidprintComponents(java.awt.Graphics g)
Prints each of the components in this container.

param
g the graphics context.
see
Component#print
see
Component#printAll

        if (isShowing()) {
	    GraphicsCallback.PrintAllCallback.getInstance().
	        runComponents(component, g, GraphicsCallback.TWO_PASSES);
	}
    
voidprintHeavyweightComponents(java.awt.Graphics g)
Prints all the heavyweight subcomponents.

        if (isShowing()) {
	    GraphicsCallback.PrintHeavyweightComponentsCallback.getInstance().
	        runComponents(component, g, GraphicsCallback.LIGHTWEIGHTS |
                                            GraphicsCallback.HEAVYWEIGHTS);
	}
    
protected voidprocessContainerEvent(java.awt.event.ContainerEvent e)
Processes container events occurring on this container by dispatching them to any registered ContainerListener objects. NOTE: This method will not be called unless container events are enabled for this component; this happens when one of the following occurs:
  • A ContainerListener object is registered via addContainerListener
  • Container events are enabled via enableEvents

Note that if the event parameter is null the behavior is unspecified and may result in an exception.

param
e the container event
see
Component#enableEvents

        ContainerListener listener = containerListener;
        if (listener != null) {
            switch(e.getID()) {
              case ContainerEvent.COMPONENT_ADDED:
                listener.componentAdded(e);
                break;
              case ContainerEvent.COMPONENT_REMOVED:
                listener.componentRemoved(e);
                break;
            }
        }
    
protected voidprocessEvent(java.awt.AWTEvent e)
Processes events on this container. If the event is a ContainerEvent, it invokes the processContainerEvent method, else it invokes its superclass's processEvent.

Note that if the event parameter is null the behavior is unspecified and may result in an exception.

param
e the event

        if (e instanceof ContainerEvent) {
            processContainerEvent((ContainerEvent)e);     
            return;
        }
	super.processEvent(e);
    
voidproxyEnableEvents(long events)
This is called by lightweight components that want the containing windowed parent to enable some kind of events on their behalf. This is needed for events that are normally only dispatched to windows to be accepted so that they can be forwarded downward to the lightweight component that has enabled them.

	if (peer instanceof LightweightPeer) {
	    // this container is lightweight.... continue sending it
	    // upward.
	    if (parent != null) {
		parent.proxyEnableEvents(events);
	    }
	} else {
	    // This is a native container, so it needs to host
	    // one of it's children.  If this function is called before
	    // a peer has been created we don't yet have a dispatcher
	    // because it has not yet been determined if this instance
	    // is lightweight.
	    if (dispatcher != null) {
		dispatcher.enableEvents(events);
	    }
	}
    
private voidreadObject(java.io.ObjectInputStream s)
Deserializes this Container from the specified ObjectInputStream.
  • Reads default serializable fields from the stream.
  • Reads a list of serializable ContainerListener(s) as optional data. If the list is null, no Listeners are installed.
  • Reads this Container's FocusTraversalPolicy, which may be null, as optional data.

param
s the ObjectInputStream to read
serial
see
#addContainerListener
see
#writeObject(ObjectOutputStream)

        ObjectInputStream.GetField f = s.readFields();
        ncomponents = f.get("ncomponents", 0);
        component = (Component[])f.get("component", new Component[0]);
        layoutMgr = (LayoutManager)f.get("layoutMgr", null);
        dispatcher = (LightweightDispatcher)f.get("dispatcher", null);
        // Old stream. Doesn't contain maxSize among Component's fields.
        if (maxSize == null) {
            maxSize = (Dimension)f.get("maxSize", null);
        }
        focusCycleRoot = f.get("focusCycleRoot", false);
        containerSerializedDataVersion = f.get("containerSerializedDataVersion", 1);
        focusTraversalPolicyProvider = f.get("focusTraversalPolicyProvider", false);

	Component component[] = this.component;
	for(int i = 0; i < ncomponents; i++) {
	    component[i].parent = this;
	    adjustListeningChildren(AWTEvent.HIERARCHY_EVENT_MASK, 
	        component[i].numListening(AWTEvent.HIERARCHY_EVENT_MASK));
	    adjustListeningChildren(AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK,
                component[i].numListening(
                    AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK));
            adjustDescendants(component[i].countHierarchyMembers());
	}
   
	Object keyOrNull;
	while(null != (keyOrNull = s.readObject())) {
	    String key = ((String)keyOrNull).intern();
	    
	    if (containerListenerK == key) {
		addContainerListener((ContainerListener)(s.readObject()));
	    } else {
		// skip value for unrecognized key
		s.readObject();
	    }
	}
  
	try {
	    Object policy = s.readObject();
	    if (policy instanceof FocusTraversalPolicy) {
		focusTraversalPolicy = (FocusTraversalPolicy)policy;
	    }
	} catch (java.io.OptionalDataException e) {
	    // JDK 1.1/1.2/1.3 instances will not have this optional data.
	    // e.eof will be true to indicate that there is no more data
	    // available for this object. If e.eof is not true, throw the
	    // exception as it might have been caused by reasons unrelated to 
	    // focusTraversalPolicy.
  
	    if (!e.eof) {
		throw e;
	    }
	}
    
public voidremove(int index)
Removes the component, specified by index, from this container. This method also notifies the layout manager to remove the component from this container's layout via the removeLayoutComponent method.

Note: If a component has been removed from a container that had been displayed, {@link #validate} must be called on that container to reflect changes. If multiple components are being removed, you can improve efficiency by calling {@link #validate} only once, after all the components have been removed.

param
index the index of the component to be removed
throws
ArrayIndexOutOfBoundsException if {@code index} is not in range {@code [0, getComponentCount()-1]}
see
#add
see
#validate
see
#getComponentCount
since
JDK1.1

	synchronized (getTreeLock()) {
            if (index < 0  || index >= ncomponents) {
                throw new ArrayIndexOutOfBoundsException(index);
            }
    	    Component comp = component[index];
	    if (peer != null) {
		comp.removeNotify();
	    }
	    if (layoutMgr != null) {
		layoutMgr.removeLayoutComponent(comp);
	    }

	    adjustListeningChildren(AWTEvent.HIERARCHY_EVENT_MASK, 
	        -comp.numListening(AWTEvent.HIERARCHY_EVENT_MASK));
	    adjustListeningChildren(AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK,
		-comp.numListening(AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK));
            adjustDescendants(-(comp.countHierarchyMembers()));

	    comp.parent = null;
	    System.arraycopy(component, index + 1,
			     component, index,
			     ncomponents - index - 1);
	    component[--ncomponents] = null;

	    if (valid) {
		invalidate();
	    }
            if (containerListener != null ||
                (eventMask & AWTEvent.CONTAINER_EVENT_MASK) != 0 ||
                Toolkit.enabledOnToolkit(AWTEvent.CONTAINER_EVENT_MASK)) {
                ContainerEvent e = new ContainerEvent(this, 
                                     ContainerEvent.COMPONENT_REMOVED,
                                     comp);
                dispatchEvent(e);
            }

	    comp.createHierarchyEvents(HierarchyEvent.HIERARCHY_CHANGED, comp,
				       this, HierarchyEvent.PARENT_CHANGED,
                                       Toolkit.enabledOnToolkit(AWTEvent.HIERARCHY_EVENT_MASK));
	    if (peer != null && layoutMgr == null && isVisible()) {
                updateCursorImmediately();
	    }
	}
    
public voidremove(java.awt.Component comp)
Removes the specified component from this container. This method also notifies the layout manager to remove the component from this container's layout via the removeLayoutComponent method.

Note: If a component has been removed from a container that had been displayed, {@link #validate} must be called on that container to reflect changes. If multiple components are being removed, you can improve efficiency by calling {@link #validate} only once, after all the components have been removed.

param
comp the component to be removed
see
#add
see
#validate
see
#remove(int)

	synchronized (getTreeLock()) {
	    if (comp.parent == this)  {
    		/* Search backwards, expect that more recent additions
		 * are more likely to be removed.
    	    	 */
		Component component[] = this.component;
		for (int i = ncomponents; --i >= 0; ) {
		    if (component[i] == comp) {
    	    	    	remove(i);
		    }
		}
	    }
	}
    
public voidremoveAll()
Removes all the components from this container. This method also notifies the layout manager to remove the components from this container's layout via the removeLayoutComponent method.

see
#add
see
#remove

	synchronized (getTreeLock()) {
	    adjustListeningChildren(AWTEvent.HIERARCHY_EVENT_MASK,
                                    -listeningChildren);
	    adjustListeningChildren(AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK,
		                    -listeningBoundsChildren);
            adjustDescendants(-descendantsCount);

	    while (ncomponents > 0) {
		Component comp = component[--ncomponents];
		component[ncomponents] = null;

		if (peer != null) {
		    comp.removeNotify();
		}
		if (layoutMgr != null) {
		    layoutMgr.removeLayoutComponent(comp);
		}
		comp.parent = null;
                if (containerListener != null ||
                   (eventMask & AWTEvent.CONTAINER_EVENT_MASK) != 0 ||
                    Toolkit.enabledOnToolkit(AWTEvent.CONTAINER_EVENT_MASK)) {
                    ContainerEvent e = new ContainerEvent(this, 
                                     ContainerEvent.COMPONENT_REMOVED,
                                     comp);
                    dispatchEvent(e);
                }

		comp.createHierarchyEvents(HierarchyEvent.HIERARCHY_CHANGED,
					   comp, this,
					   HierarchyEvent.PARENT_CHANGED,
                                           Toolkit.enabledOnToolkit(AWTEvent.HIERARCHY_EVENT_MASK));
	    }
	    if (peer != null && layoutMgr == null && isVisible()) {
                updateCursorImmediately();
	    }
	    if (valid) {
		invalidate();
	    }
	}
    
public synchronized voidremoveContainerListener(java.awt.event.ContainerListener l)
Removes the specified container listener so it no longer receives container events from this container. If l is null, no exception is thrown and no action is performed.

Refer to AWT Threading Issues for details on AWT's threading model.

param
l the container listener
see
#addContainerListener
see
#getContainerListeners

	if (l == null) {
	    return;
	}
	containerListener = AWTEventMulticaster.remove(containerListener, l);
    
private voidremoveDelicately(java.awt.Component comp, java.awt.Container newParent, int newIndex)
Removes component comp from this container without making unneccessary changes and generating unneccessary events. This function intended to perform optimized remove, for example, if newParent and current parent are the same it just changes index without calling removeNotify. Note: Should be called while holding treeLock

since:
1.5

        checkTreeLock();

        int index = getComponentZOrder(comp);
        if (isRemoveNotifyNeeded(comp, this, newParent)) {                
            comp.removeNotify();
        }
        if (newParent != this) {
            if (layoutMgr != null) {
                layoutMgr.removeLayoutComponent(comp);
            }
            adjustListeningChildren(AWTEvent.HIERARCHY_EVENT_MASK, 
                                    -comp.numListening(AWTEvent.HIERARCHY_EVENT_MASK));
            adjustListeningChildren(AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK,
                                    -comp.numListening(AWTEvent.HIERARCHY_BOUNDS_EVENT_MASK));
            adjustDescendants(-(comp.countHierarchyMembers()));

            comp.parent = null;
            System.arraycopy(component, index + 1,
                             component, index,
                             ncomponents - index - 1);
            component[--ncomponents] = null;

            if (valid) {
                invalidate();
            }
        } else {
            if (newIndex > index) { // 2->4: 012345 -> 013425, 2->5: 012345 -> 013452
                if (newIndex-index > 0) {
                    System.arraycopy(component, index+1, component, index, newIndex-index);
                }
            } else { // 4->2: 012345 -> 014235
                if (index-newIndex > 0) {
                    System.arraycopy(component, newIndex, component, newIndex+1, index-newIndex);
                }
            }
            component[newIndex] = comp;
        }
        if (comp.parent == null) { // was actually removed
            if (containerListener != null ||
                (eventMask & AWTEvent.CONTAINER_EVENT_MASK) != 0 ||
                Toolkit.enabledOnToolkit(AWTEvent.CONTAINER_EVENT_MASK)) {
                ContainerEvent e = new ContainerEvent(this, 
                                                      ContainerEvent.COMPONENT_REMOVED,
                                                      comp);
                dispatchEvent(e);

            }
            comp.createHierarchyEvents(HierarchyEvent.HIERARCHY_CHANGED, comp,
                                       this, HierarchyEvent.PARENT_CHANGED,
                                       Toolkit.enabledOnToolkit(AWTEvent.HIERARCHY_EVENT_MASK));
            if (peer != null && layoutMgr == null && isVisible()) {
                updateCursorImmediately();
            }
        }
    
public voidremoveNotify()
Makes this Container undisplayable by removing its connection to its native screen resource. Making a container undisplayable will cause all of its children to be made undisplayable. This method is called by the toolkit internally and should not be called directly by programs.

see
Component#isDisplayable
see
#addNotify

        synchronized (getTreeLock()) {
	    int ncomponents = this.ncomponents;
            Component component[] = this.component;
            for (int i = ncomponents-1 ; i >= 0 ; i--) {
                if( component[i] != null )
	        component[i].removeNotify();
	    }
	    if ( dispatcher != null ) {
		dispatcher.dispose();
        dispatcher = null;
	    }
	    super.removeNotify();
        }
    
private voidreparentChild(java.awt.Component comp)
Reparents child component peer to this container peer. Container must be heavyweight.

since
1.5

        checkTreeLock();
        if (comp == null) {
            return;
        }
        if (comp.isLightweight()) {
            // If component is lightweight container we need to reparent all its explicit  heavyweight children
            if (comp instanceof Container) {
                // Traverse component's tree till depth-first until encountering heavyweight component
                reparentTraverse((ContainerPeer)getPeer(), (Container)comp);
            }
        } else {
            comp.getPeer().reparent((ContainerPeer)getPeer());
        }
    
private voidreparentTraverse(java.awt.peer.ContainerPeer parentPeer, java.awt.Container child)
Traverses the tree of components and reparents children heavyweight component to new heavyweight parent.

since
1.5

        checkTreeLock();

        for (int i = 0; i < child.getComponentCount(); i++) {
            Component comp = child.getComponent(i);
            if (comp.isLightweight()) {
                // If components is lightweight check if it is container
                // If it is container it might contain heavyweight children we need to reparent
                if (comp instanceof Container) {
                    reparentTraverse(parentPeer, (Container)comp);
                }
            } else {
                // Q: Need to update NativeInLightFixer?
                comp.getPeer().reparent(parentPeer);
            }
        }
    
public voidsetComponentZOrder(java.awt.Component comp, int index)
Moves the specified component to the specified z-order index in the container. The z-order determines the order that components are painted; the component with the highest z-order paints first and the component with the lowest z-order paints last. Where components overlap, the component with the lower z-order paints over the component with the higher z-order.

If the component is a child of some other container, it is removed from that container before being added to this container. The important difference between this method and java.awt.Container.add(Component, int) is that this method doesn't call removeNotify on the component while removing it from its previous container unless necessary and when allowed by the underlying native windowing system. This way, if the component has the keyboard focus, it maintains the focus when moved to the new position.

This property is guaranteed to apply only to lightweight non-Container components.

Note: Not all platforms support changing the z-order of heavyweight components from one container into another without the call to removeNotify. There is no way to detect whether a platform supports this, so developers shouldn't make any assumptions.

param
comp the component to be moved
param
index the position in the container's list to insert the component, where getComponentCount() appends to the end
exception
NullPointerException if comp is null
exception
IllegalArgumentException if comp is one of the container's parents
exception
IllegalArgumentException if index is not in the range [0, getComponentCount()] for moving between containers, or not in the range [0, getComponentCount()-1] for moving inside a container
exception
IllegalArgumentException if adding a container to itself
exception
IllegalArgumentException if adding a Window to a container
see
#getComponentZOrder(java.awt.Component)
since
1.5

         synchronized (getTreeLock()) {
             // Store parent because remove will clear it
             Container curParent = comp.parent; 
             if (curParent == this && index == getComponentZOrder(comp)) {
                 return;
             }
             checkAdding(comp, index);
             if (curParent != null) {
                 curParent.removeDelicately(comp, this, index);
             }
             
             addDelicately(comp, curParent, index);
         }
    
public voidsetFocusCycleRoot(boolean focusCycleRoot)
Sets whether this Container is the root of a focus traversal cycle. Once focus enters a traversal cycle, typically it cannot leave it via focus traversal unless one of the up- or down-cycle keys is pressed. Normal traversal is limited to this Container, and all of this Container's descendants that are not descendants of inferior focus cycle roots. Note that a FocusTraversalPolicy may bend these restrictions, however. For example, ContainerOrderFocusTraversalPolicy supports implicit down-cycle traversal.

The alternative way to specify the traversal order of this Container's children is to make this Container a focus traversal policy provider.

param
focusCycleRoot indicates whether this Container is the root of a focus traversal cycle
see
#isFocusCycleRoot()
see
#setFocusTraversalPolicy
see
#getFocusTraversalPolicy
see
ContainerOrderFocusTraversalPolicy
see
#setFocusTraversalPolicyProvider
since
1.4
beaninfo
bound: true

        boolean oldFocusCycleRoot;
	synchronized (this) {
	    oldFocusCycleRoot = this.focusCycleRoot;
	    this.focusCycleRoot = focusCycleRoot;
	}
	firePropertyChange("focusCycleRoot", oldFocusCycleRoot,
			   focusCycleRoot);
    
public voidsetFocusTraversalKeys(int id, java.util.Set keystrokes)
Sets the focus traversal keys for a given traversal operation for this Container.

The default values for a Container's focus traversal keys are implementation-dependent. Sun recommends that all implementations for a particular native platform use the same default values. The recommendations for Windows and Unix are listed below. These recommendations are used in the Sun AWT implementations.
Identifier Meaning Default
KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS Normal forward keyboard traversal TAB on KEY_PRESSED, CTRL-TAB on KEY_PRESSED
KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS Normal reverse keyboard traversal SHIFT-TAB on KEY_PRESSED, CTRL-SHIFT-TAB on KEY_PRESSED
KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS Go up one focus traversal cycle none
KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS Go down one focus traversal cycle none
To disable a traversal key, use an empty Set; Collections.EMPTY_SET is recommended.

Using the AWTKeyStroke API, client code can specify on which of two specific KeyEvents, KEY_PRESSED or KEY_RELEASED, the focus traversal operation will occur. Regardless of which KeyEvent is specified, however, all KeyEvents related to the focus traversal key, including the associated KEY_TYPED event, will be consumed, and will not be dispatched to any Container. It is a runtime error to specify a KEY_TYPED event as mapping to a focus traversal operation, or to map the same event to multiple default focus traversal operations.

If a value of null is specified for the Set, this Container inherits the Set from its parent. If all ancestors of this Container have null specified for the Set, then the current KeyboardFocusManager's default Set is used.

param
id one of KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS, or KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS
param
keystrokes the Set of AWTKeyStroke for the specified operation
see
#getFocusTraversalKeys
see
KeyboardFocusManager#FORWARD_TRAVERSAL_KEYS
see
KeyboardFocusManager#BACKWARD_TRAVERSAL_KEYS
see
KeyboardFocusManager#UP_CYCLE_TRAVERSAL_KEYS
see
KeyboardFocusManager#DOWN_CYCLE_TRAVERSAL_KEYS
throws
IllegalArgumentException if id is not one of KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS, or KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS, or if keystrokes contains null, or if any Object in keystrokes is not an AWTKeyStroke, or if any keystroke represents a KEY_TYPED event, or if any keystroke already maps to another focus traversal operation for this Container
since
1.4
beaninfo
bound: true

        if (id < 0 || id >= KeyboardFocusManager.TRAVERSAL_KEY_LENGTH) {
            throw new IllegalArgumentException("invalid focus traversal key identifier");
        }
          
        // Don't call super.setFocusTraversalKey. The Component parameter check
	// does not allow DOWN_CYCLE_TRAVERSAL_KEYS, but we do.
        setFocusTraversalKeys_NoIDCheck(id, keystrokes);
    
public voidsetFocusTraversalPolicy(java.awt.FocusTraversalPolicy policy)
Sets the focus traversal policy that will manage keyboard traversal of this Container's children, if this Container is a focus cycle root. If the argument is null, this Container inherits its policy from its focus- cycle-root ancestor. If the argument is non-null, this policy will be inherited by all focus-cycle-root children that have no keyboard- traversal policy of their own (as will, recursively, their focus-cycle- root children).

If this Container is not a focus cycle root, the policy will be remembered, but will not be used or inherited by this or any other Containers until this Container is made a focus cycle root.

param
policy the new focus traversal policy for this Container
see
#getFocusTraversalPolicy
see
#setFocusCycleRoot
see
#isFocusCycleRoot
since
1.4
beaninfo
bound: true

        FocusTraversalPolicy oldPolicy;
	synchronized (this) {
	    oldPolicy = this.focusTraversalPolicy;
	    this.focusTraversalPolicy = policy;
	}
	firePropertyChange("focusTraversalPolicy", oldPolicy, policy);
    
public final voidsetFocusTraversalPolicyProvider(boolean provider)
Sets whether this container will be used to provide focus traversal policy. Container with this property as true will be used to acquire focus traversal policy instead of closest focus cycle root ancestor.

param
provider indicates whether this container will be used to provide focus traversal policy
see
#setFocusTraversalPolicy
see
#getFocusTraversalPolicy
see
#isFocusTraversalPolicyProvider
since
1.5
beaninfo
bound: true

        boolean oldProvider;
        synchronized(this) {
            oldProvider = focusTraversalPolicyProvider;
            focusTraversalPolicyProvider = provider;
        }
        firePropertyChange("focusTraversalPolicyProvider", oldProvider, provider);
    
public voidsetFont(java.awt.Font f)
Sets the font of this container.

param
f The font to become this container's font.
see
Component#getFont
since
JDK1.0

        boolean shouldinvalidate = false;

	Font oldfont = getFont();
	super.setFont(f);
	Font newfont = getFont();
	if (newfont != oldfont && (oldfont == null ||
				   !oldfont.equals(newfont))) {
	    invalidateTree();
	}
    
public voidsetLayout(java.awt.LayoutManager mgr)
Sets the layout manager for this container.

param
mgr the specified layout manager
see
#doLayout
see
#getLayout

	layoutMgr = mgr;
	if (valid) {
	    invalidate();
	}
    
private voidstartLWModal()

        // Store the app context on which this component is being shown.
        // Event dispatch thread of this app context will be sleeping until
        // we wake it by any event from hideAndDisposeHandler().
        modalAppContext = AppContext.getAppContext();

        // keep the KeyEvents from being dispatched
        // until the focus has been transfered
        long time = Toolkit.getEventQueue().getMostRecentEventTime();
        Component predictedFocusOwner = (Component.isInstanceOf(this, "javax.swing.JInternalFrame")) ? ((javax.swing.JInternalFrame)(this)).getMostRecentFocusOwner() : null;
        if (predictedFocusOwner != null) {
            KeyboardFocusManager.getCurrentKeyboardFocusManager().
                enqueueKeyEvents(time, predictedFocusOwner); 
        }
        // We have two mechanisms for blocking: 1. If we're on the
        // EventDispatchThread, start a new event pump. 2. If we're
        // on any other thread, call wait() on the treelock.
        final Container nativeContainer; 
        synchronized (getTreeLock()) {
            nativeContainer = getHeavyweightContainer();
            if (nativeContainer.modalComp != null) {
                this.modalComp =  nativeContainer.modalComp;
                nativeContainer.modalComp = this;
                return;
            }
            else {
                nativeContainer.modalComp = this;
            }
        }

        Runnable pumpEventsForHierarchy = new Runnable() {
            public void run() {
                EventDispatchThread dispatchThread =
                    (EventDispatchThread)Thread.currentThread();
                dispatchThread.pumpEventsForHierarchy(
                        new Conditional() {
                        public boolean evaluate() {
                        return ((windowClosingException == null) && (nativeContainer.modalComp != null)) ;
                        }
                        }, Container.this);
            }
        };

        if (EventQueue.isDispatchThread()) {
            SequencedEvent currentSequencedEvent =
                KeyboardFocusManager.getCurrentKeyboardFocusManager().
                getCurrentSequencedEvent();
            if (currentSequencedEvent != null) {
                currentSequencedEvent.dispose();
            }

            pumpEventsForHierarchy.run();
        } else {
            synchronized (getTreeLock()) {
                Toolkit.getEventQueue().
                    postEvent(new PeerEvent(this,
                                pumpEventsForHierarchy,
                                PeerEvent.PRIORITY_EVENT));
                while (windowClosingException == null) {
                    try {
                        getTreeLock().wait();
                    } catch (InterruptedException e) {
                        break;
                    }
                }
            }
        }
        if (windowClosingException != null) {
            windowClosingException.fillInStackTrace();
            throw windowClosingException;
        }
        if (predictedFocusOwner != null) {
            KeyboardFocusManager.getCurrentKeyboardFocusManager().
                dequeueKeyEvents(time, predictedFocusOwner);
        }
    
private voidstopLWModal()

        synchronized (getTreeLock()) {
            if (modalAppContext != null) {
                Container nativeContainer = getHeavyweightContainer();
                if(nativeContainer != null) { 
                    if (this.modalComp !=  null) {
                        nativeContainer.modalComp = this.modalComp; 
                        this.modalComp = null;
                        return;
                    }
                    else {
                        nativeContainer.modalComp = null;
                    }
                }
                // Wake up event dispatch thread on which the dialog was 
                // initially shown
                SunToolkit.postEvent(modalAppContext, 
                        new PeerEvent(this, 
                                new WakingRunnable(),
                                PeerEvent.PRIORITY_EVENT));
            }
            EventQueue.invokeLater(new WakingRunnable());
            getTreeLock().notifyAll();
        }
    
public voidtransferFocusBackward()

        if (isFocusCycleRoot()) {
            Container root = findTraversalRoot();
            Component comp = this;
            while (root != null && 
                   !(root.isShowing() && 
                     root.isFocusable() && 
                     root.isEnabled())) 
            {
                comp = root;
                root = comp.getFocusCycleRootAncestor();
            }
            if (root != null) {
                FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
                Component toFocus = policy.getComponentBefore(root, comp);
                if (toFocus == null) {
                    toFocus = policy.getDefaultComponent(root);
                }
                if (toFocus != null) {
                    toFocus.requestFocus(CausedFocusEvent.Cause.TRAVERSAL_BACKWARD);
                }
            }
        } else {
            // I only have one root, so the general case will suffice
            super.transferFocusBackward();
        }
    
public voidtransferFocusDownCycle()
Transfers the focus down one focus traversal cycle. If this Container is a focus cycle root, then the focus owner is set to this Container's default Component to focus, and the current focus cycle root is set to this Container. If this Container is not a focus cycle root, then no focus traversal operation occurs.

see
Component#requestFocus()
see
#isFocusCycleRoot
see
#setFocusCycleRoot
since
1.4

        if (isFocusCycleRoot()) {
	    KeyboardFocusManager.getCurrentKeyboardFocusManager().
	        setGlobalCurrentFocusCycleRoot(this);
	    Component toFocus = getFocusTraversalPolicy().
	        getDefaultComponent(this);
	    if (toFocus != null) {
	        toFocus.requestFocus(CausedFocusEvent.Cause.TRAVERSAL_DOWN);
	    }
	}
    
public voidupdate(java.awt.Graphics g)
Updates the container. This forwards the update to any lightweight components that are children of this container. If this method is reimplemented, super.update(g) should be called so that lightweight components are properly rendered. If a child component is entirely clipped by the current clipping setting in g, update() will not be forwarded to that child.

param
g the specified Graphics window
see
Component#update(Graphics)

        if (isShowing()) {
            if (! (peer instanceof LightweightPeer)) {
                g.clearRect(0, 0, width, height);
            }
            paint(g);
        }
    
public voidvalidate()
Validates this container and all of its subcomponents.

The validate method is used to cause a container to lay out its subcomponents again. It should be invoked when this container's subcomponents are modified (added to or removed from the container, or layout-related information changed) after the container has been displayed.

If this {@code Container} is not valid, this method invokes the {@code validateTree} method and marks this {@code Container} as valid. Otherwise, no action is performed.

see
#add(java.awt.Component)
see
Component#invalidate
see
javax.swing.JComponent#revalidate()
see
#validateTree

        /* Avoid grabbing lock unless really necessary. */
	if (!valid) {
	    boolean updateCur = false;
	    synchronized (getTreeLock()) {
		if (!valid && peer != null) {
		    ContainerPeer p = null;
		    if (peer instanceof ContainerPeer) {
			p = (ContainerPeer) peer;
		    }
		    if (p != null) {
			p.beginValidate();
		    }
		    validateTree();
		    valid = true;
		    if (p != null) {
			p.endValidate();
			updateCur = isVisible();
		    }
		}
	    }
	    if (updateCur) {
                updateCursorImmediately();
	    }
	}
    
protected voidvalidateTree()
Recursively descends the container tree and recomputes the layout for any subtrees marked as needing it (those marked as invalid). Synchronization should be provided by the method that calls this one: validate.

see
#doLayout
see
#validate

	if (!valid) {
	    if (peer instanceof ContainerPeer) {
		((ContainerPeer)peer).beginLayout();
	    }
	    doLayout();
            Component component[] = this.component;
	    for (int i = 0 ; i < ncomponents ; ++i) {
		Component comp = component[i];
		if (   (comp instanceof Container) 
	            && !(comp instanceof Window)
		    && !comp.valid) {
		    ((Container)comp).validateTree();
		} else {
		    comp.validate();
		}
	    }
	    if (peer instanceof ContainerPeer) {
		((ContainerPeer)peer).endLayout();
	    }
	}
	valid = true;
    
private voidwriteObject(java.io.ObjectOutputStream s)
Serializes this Container to the specified ObjectOutputStream.
  • Writes default serializable fields to the stream.
  • Writes a list of serializable ContainerListener(s) as optional data. The non-serializable ContainerListner(s) are detected and no attempt is made to serialize them.
  • Write this Container's FocusTraversalPolicy if and only if it is Serializable; otherwise, null is written.

param
s the ObjectOutputStream to write
serialData
null terminated sequence of 0 or more pairs; the pair consists of a String and Object; the String indicates the type of object and is one of the following: containerListenerK indicating an ContainerListener object; the Container's FocusTraversalPolicy, or null
see
AWTEventMulticaster#save(java.io.ObjectOutputStream, java.lang.String, java.util.EventListener)
see
Container#containerListenerK
see
#readObject(ObjectInputStream)

  
                                                                                                                                                                    
          
        ObjectOutputStream.PutField f = s.putFields();
        f.put("ncomponents", ncomponents);
        f.put("component", component);
        f.put("layoutMgr", layoutMgr);
        f.put("dispatcher", dispatcher);
        f.put("maxSize", maxSize);
        f.put("focusCycleRoot", focusCycleRoot);
        f.put("containerSerializedDataVersion", containerSerializedDataVersion);
        f.put("focusTraversalPolicyProvider", focusTraversalPolicyProvider);
        s.writeFields();
	
	AWTEventMulticaster.save(s, containerListenerK, containerListener);
	s.writeObject(null);
	
	if (focusTraversalPolicy instanceof java.io.Serializable) {
	    s.writeObject(focusTraversalPolicy);
	} else {
	    s.writeObject(null);
	}