/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can obtain
* a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
* or glassfish/bootstrap/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
* Sun designates this particular file as subject to the "Classpath" exception
* as provided by Sun in the GPL Version 2 section of the License file that
* accompanied this code. If applicable, add the following below the License
* Header, with the fields enclosed by brackets [] replaced by your own
* identifying information: "Portions Copyrighted [year]
* [name of copyright owner]"
*
* Contributor(s):
*
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
/*
* PersistenceElement.java
*
* Created on February 28, 2000, 3:37 PM
*/
package com.sun.jdo.api.persistence.model.jdo;
import java.util.ResourceBundle;
import java.beans.PropertyChangeListener;
import java.beans.VetoableChangeListener;
import java.text.Collator;
import com.sun.jdo.api.persistence.model.ModelException;
import com.sun.jdo.spi.persistence.utility.I18NHelper;
/**
*
* @author raccah
* @version %I%
*/
public abstract class PersistenceElement extends Object
implements PersistenceElementProperties, Comparable
{
/** I18N message handler */
private static final ResourceBundle _messages = I18NHelper.loadBundle(
"com.sun.jdo.api.persistence.model.Bundle", // NOI18N
PersistenceElement.class.getClassLoader());
/** Implementation */
Impl _impl;
/** Create new PersistenceElement with no implementation.
* This constructor should only be used for cloning and archiving.
*/
public PersistenceElement ()
{
this(null);
}
/** Create new PersistenceElement with the provided implementation. The
* implementation is responsible for storing all properties of the object.
* @param impl the implementation to use
*/
protected PersistenceElement (PersistenceElement.Impl impl)
{
setImpl(impl);
}
/** @return implemetation factory for this element
*/
public final Impl getImpl () { return _impl; }
/** @return I18N message handler for this element
*/
protected static final ResourceBundle getMessages () { return _messages; }
/** Add a property change listener.
* @param l the listener to add
* @see PersistenceElementProperties
*/
public final void addPropertyChangeListener (PropertyChangeListener l)
{
getImpl().addPropertyChangeListener(l);
}
/** Remove a property change listener.
* @param l the listener to remove
* @see PersistenceElementProperties
*/
public final void removePropertyChangeListener (PropertyChangeListener l)
{
getImpl().removePropertyChangeListener(l);
}
/** Add a vetoable change listener.
* @param l the listener to add
* @see PersistenceElementProperties
*/
public final void addVetoableChangeListener (VetoableChangeListener l)
{
getImpl().addVetoableChangeListener(l);
}
/** Remove a vetoable change listener.
* @param l the listener to remove
* @see PersistenceElementProperties
*/
public final void removeVetoableChangeListener (VetoableChangeListener l)
{
getImpl().removeVetoableChangeListener(l);
}
/** Get the name of this persistence element.
* @return the name
*/
public String getName() { return getImpl().getName(); }
/** Set the name of this persistence element.
* @param name the name
* @exception ModelException if impossible
*/
public void setName (String name) throws ModelException
{
getImpl().setName(name);
}
/** Overrides Object's <code>toString</code> method to return the name
* of this persistence element.
* @return a string representation of the object
*/
public String toString () { return getName(); }
/** Overrides Object's <code>equals</code> method by comparing the name of this persistence element
* with the name of the argument obj. The method returns <code>false</code> if obj does not have
* the same dynamic type as this persistence element.
* @return <code>true</code> if this object is the same as the obj argument; <code>false</code> otherwise.
* @param obj the reference object with which to compare.
*/
public boolean equals(Object obj)
{
if (obj == null)
return false;
if (obj == this)
return true;
// check for the right class and then do the name check by calling compareTo.
return (getClass() == obj.getClass()) && (compareTo(obj) == 0);
}
/** Overrides Object's <code>hashCode</code> method to return the hashCode of this persistence element's name.
* @return a hash code value for this object.
*/
public int hashCode()
{
return (getName()==null) ? 0 : getName().hashCode();
}
//================= implementation of Comparable ================
/** Compares this object with the specified object for order. Returns a negative integer, zero,
* or a positive integer as this object is less than, equal to, or greater than the specified object.
* The specified object must be persistence element, meaning it must be an instance of class
* PersistenceElement or any subclass. If not a ClassCastException is thrown.
* The order of PersistenceElement objects is defined by the order of their names.
* Persistence elements without name are considered to be less than any named persistence element.
* @param o the Object to be compared.
* @return a negative integer, zero, or a positive integer as this object is less than, equal to,
* or greater than the specified object.
* @exception ClassCastException - if the specified object is null or is not an instance of PersistenceElement
*/
public int compareTo(Object o)
{
// null is not allowed
if (o == null)
throw new ClassCastException();
if (o == this)
return 0;
String thisName = getName();
// the following statement throws a ClassCastException if o is not a PersistenceElement
String otherName = ((PersistenceElement)o).getName();
// if this does not have a name it should compare less than any named object
if (thisName == null)
return (otherName == null) ? 0 : -1;
// if this is named and o does not have a name it should compare greater
if (otherName == null)
return 1;
// now we know that this and o are named persistence elements =>
// use locale-sensitive String comparison
int ret = Collator.getInstance().compare(thisName, otherName);
// if both names are equal, both objects might have different types.
// If so order both objects by their type names (necessary to be consistent with equals)
if ((ret == 0) && (getClass() != o.getClass()))
ret = getClass().getName().compareTo(o.getClass().getName());
return ret;
}
//=============== extra set methods needed for xml archiver ==============
/** Set the implementation factory of this persistence element.
* This method should only be used internally and for cloning
* and archiving.
* @param impl the implementation to use
*/
public void setImpl (PersistenceElement.Impl impl)
{
_impl = impl;
if (_impl != null)
getImpl().attachToElement(this);
}
/** Pluggable implementation of the storage of element properties.
* @see PersistenceElement#PersistenceElement
*/
public interface Impl
{
/** Add some items. */
public static final int ADD = 1;
/** Remove some items. */
public static final int REMOVE = -1;
/** Set some items, replacing the old ones. */
public static final int SET = 0;
/** Called to attach the implementation to a specific
* element. Will be called in the element's constructor.
* Allows implementors of this interface to store a reference to the
* holder class, useful for implementing the property change listeners.
*
* @param element the element to attach to
*/
public void attachToElement (PersistenceElement element);
/** Add a property change listener.
* @param l the listener to add
*/
public void addPropertyChangeListener (PropertyChangeListener l);
/** Remove a property change listener.
* @param l the listener to remove
*/
public void removePropertyChangeListener (PropertyChangeListener l);
/** Add a vetoable change listener.
* @param l the listener to add
*/
public void addVetoableChangeListener (VetoableChangeListener l);
/** Remove a vetoable change listener.
* @param l the listener to remove
*/
public void removeVetoableChangeListener (VetoableChangeListener l);
/** Get the name of this persistence element.
* @return the name
*/
public String getName ();
/** Set the name of this persistence element.
* @param name the name
* @exception ModelException if impossible
*/
public void setName (String name) throws ModelException;
}
}
|
