/*
* @(#)Introspector.java 1.144 06/05/23
*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package java.beans;
import java.lang.ref.Reference;
import java.lang.ref.SoftReference;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.Collections;
import java.util.Map;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.EventListener;
import java.util.List;
import java.util.WeakHashMap;
import java.util.TreeMap;
import sun.reflect.misc.ReflectUtil;
/**
* The Introspector class provides a standard way for tools to learn about
* the properties, events, and methods supported by a target Java Bean.
* <p>
* For each of those three kinds of information, the Introspector will
* separately analyze the bean's class and superclasses looking for
* either explicit or implicit information and use that information to
* build a BeanInfo object that comprehensively describes the target bean.
* <p>
* For each class "Foo", explicit information may be available if there exists
* a corresponding "FooBeanInfo" class that provides a non-null value when
* queried for the information. We first look for the BeanInfo class by
* taking the full package-qualified name of the target bean class and
* appending "BeanInfo" to form a new class name. If this fails, then
* we take the final classname component of this name, and look for that
* class in each of the packages specified in the BeanInfo package search
* path.
* <p>
* Thus for a class such as "sun.xyz.OurButton" we would first look for a
* BeanInfo class called "sun.xyz.OurButtonBeanInfo" and if that failed we'd
* look in each package in the BeanInfo search path for an OurButtonBeanInfo
* class. With the default search path, this would mean looking for
* "sun.beans.infos.OurButtonBeanInfo".
* <p>
* If a class provides explicit BeanInfo about itself then we add that to
* the BeanInfo information we obtained from analyzing any derived classes,
* but we regard the explicit information as being definitive for the current
* class and its base classes, and do not proceed any further up the superclass
* chain.
* <p>
* If we don't find explicit BeanInfo on a class, we use low-level
* reflection to study the methods of the class and apply standard design
* patterns to identify property accessors, event sources, or public
* methods. We then proceed to analyze the class's superclass and add
* in the information from it (and possibly on up the superclass chain).
*
* <p>
* Because the Introspector caches BeanInfo classes for better performance,
* take care if you use it in an application that uses
* multiple class loaders.
* In general, when you destroy a <code>ClassLoader</code>
* that has been used to introspect classes,
* you should use the
* {@link #flushCaches <code>Introspector.flushCaches</code>}
* or
* {@link #flushFromCaches <code>Introspector.flushFromCaches</code>} method
* to flush all of the introspected classes out of the cache.
*
* <P>
* For more information about introspection and design patterns, please
* consult the
* <a href="http://java.sun.com/products/javabeans/docs/index.html">JavaBeans specification</a>.
*/
public class Introspector {
// Flags that can be used to control getBeanInfo:
public final static int USE_ALL_BEANINFO = 1;
public final static int IGNORE_IMMEDIATE_BEANINFO = 2;
public final static int IGNORE_ALL_BEANINFO = 3;
// Static Caches to speed up introspection.
private static Map declaredMethodCache =
Collections.synchronizedMap(new WeakHashMap());
private static Map beanInfoCache =
Collections.synchronizedMap(new WeakHashMap());
private Class beanClass;
private BeanInfo explicitBeanInfo;
private BeanInfo superBeanInfo;
private BeanInfo additionalBeanInfo[];
private boolean propertyChangeSource = false;
private static Class eventListenerType = EventListener.class;
// These should be removed.
private String defaultEventName;
private String defaultPropertyName;
private int defaultEventIndex = -1;
private int defaultPropertyIndex = -1;
// Methods maps from Method objects to MethodDescriptors
private Map methods;
// properties maps from String names to PropertyDescriptors
private Map properties;
// events maps from String names to EventSetDescriptors
private Map events;
private final static String DEFAULT_INFO_PATH = "sun.beans.infos";
private static String[] searchPath = { DEFAULT_INFO_PATH };
private final static EventSetDescriptor[] EMPTY_EVENTSETDESCRIPTORS = new EventSetDescriptor[0];
private static final String ADD_PREFIX = "add";
private static final String REMOVE_PREFIX = "remove";
private static final String GET_PREFIX = "get";
private static final String SET_PREFIX = "set";
private static final String IS_PREFIX = "is";
private static final String BEANINFO_SUFFIX = "BeanInfo";
//======================================================================
// Public methods
//======================================================================
/**
* Introspect on a Java Bean and learn about all its properties, exposed
* methods, and events.
* <p>
* If the BeanInfo class for a Java Bean has been previously Introspected
* then the BeanInfo class is retrieved from the BeanInfo cache.
*
* @param beanClass The bean class to be analyzed.
* @return A BeanInfo object describing the target bean.
* @exception IntrospectionException if an exception occurs during
* introspection.
* @see #flushCaches
* @see #flushFromCaches
*/
public static BeanInfo getBeanInfo(Class<?> beanClass)
throws IntrospectionException
{
if (!ReflectUtil.isPackageAccessible(beanClass)) {
return (new Introspector(beanClass, null, USE_ALL_BEANINFO)).getBeanInfo();
}
BeanInfo bi = (BeanInfo)beanInfoCache.get(beanClass);
if (bi == null) {
bi = (new Introspector(beanClass, null, USE_ALL_BEANINFO)).getBeanInfo();
beanInfoCache.put(beanClass, bi);
}
return bi;
}
/**
* Introspect on a Java bean and learn about all its properties, exposed
* methods, and events, subject to some control flags.
* <p>
* If the BeanInfo class for a Java Bean has been previously Introspected
* based on the same arguments then the BeanInfo class is retrieved
* from the BeanInfo cache.
*
* @param beanClass The bean class to be analyzed.
* @param flags Flags to control the introspection.
* If flags == USE_ALL_BEANINFO then we use all of the BeanInfo
* classes we can discover.
* If flags == IGNORE_IMMEDIATE_BEANINFO then we ignore any
* BeanInfo associated with the specified beanClass.
* If flags == IGNORE_ALL_BEANINFO then we ignore all BeanInfo
* associated with the specified beanClass or any of its
* parent classes.
* @return A BeanInfo object describing the target bean.
* @exception IntrospectionException if an exception occurs during
* introspection.
*/
public static BeanInfo getBeanInfo(Class<?> beanClass, int flags)
throws IntrospectionException {
return getBeanInfo(beanClass, null, flags);
}
/**
* Introspect on a Java bean and learn all about its properties, exposed
* methods, below a given "stop" point.
* <p>
* If the BeanInfo class for a Java Bean has been previously Introspected
* based on the same arguments, then the BeanInfo class is retrieved
* from the BeanInfo cache.
*
* @param beanClass The bean class to be analyzed.
* @param stopClass The baseclass at which to stop the analysis. Any
* methods/properties/events in the stopClass or in its baseclasses
* will be ignored in the analysis.
* @exception IntrospectionException if an exception occurs during
* introspection.
*/
public static BeanInfo getBeanInfo(Class<?> beanClass, Class<?> stopClass)
throws IntrospectionException {
return getBeanInfo(beanClass, stopClass, USE_ALL_BEANINFO);
}
/**
* Only called from the public getBeanInfo methods. This method caches
* the Introspected BeanInfo based on the arguments.
*/
private static BeanInfo getBeanInfo(Class beanClass, Class stopClass,
int flags) throws IntrospectionException {
BeanInfo bi;
if (stopClass == null && flags == USE_ALL_BEANINFO) {
// Same parameters to take advantage of caching.
bi = getBeanInfo(beanClass);
} else {
bi = (new Introspector(beanClass, stopClass, flags)).getBeanInfo();
}
return bi;
// Old behaviour: Make an independent copy of the BeanInfo.
//return new GenericBeanInfo(bi);
}
/**
* Utility method to take a string and convert it to normal Java variable
* name capitalization. This normally means converting the first
* character from upper case to lower case, but in the (unusual) special
* case when there is more than one character and both the first and
* second characters are upper case, we leave it alone.
* <p>
* Thus "FooBah" becomes "fooBah" and "X" becomes "x", but "URL" stays
* as "URL".
*
* @param name The string to be decapitalized.
* @return The decapitalized version of the string.
*/
public static String decapitalize(String name) {
if (name == null || name.length() == 0) {
return name;
}
if (name.length() > 1 && Character.isUpperCase(name.charAt(1)) &&
Character.isUpperCase(name.charAt(0))){
return name;
}
char chars[] = name.toCharArray();
chars[0] = Character.toLowerCase(chars[0]);
return new String(chars);
}
/**
* Gets the list of package names that will be used for
* finding BeanInfo classes.
*
* @return The array of package names that will be searched in
* order to find BeanInfo classes. The default value
* for this array is implementation-dependent; e.g.
* Sun implementation initially sets to {"sun.beans.infos"}.
*/
public static synchronized String[] getBeanInfoSearchPath() {
// Return a copy of the searchPath.
String result[] = new String[searchPath.length];
for (int i = 0; i < searchPath.length; i++) {
result[i] = searchPath[i];
}
return result;
}
/**
* Change the list of package names that will be used for
* finding BeanInfo classes. The behaviour of
* this method is undefined if parameter path
* is null.
*
* <p>First, if there is a security manager, its <code>checkPropertiesAccess</code>
* method is called. This could result in a SecurityException.
*
* @param path Array of package names.
* @exception SecurityException if a security manager exists and its
* <code>checkPropertiesAccess</code> method doesn't allow setting
* of system properties.
* @see SecurityManager#checkPropertiesAccess
*/
public static synchronized void setBeanInfoSearchPath(String path[]) {
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
sm.checkPropertiesAccess();
}
searchPath = path;
}
/**
* Flush all of the Introspector's internal caches. This method is
* not normally required. It is normally only needed by advanced
* tools that update existing "Class" objects in-place and need
* to make the Introspector re-analyze existing Class objects.
*/
public static void flushCaches() {
beanInfoCache.clear();
declaredMethodCache.clear();
}
/**
* Flush the Introspector's internal cached information for a given class.
* This method is not normally required. It is normally only needed
* by advanced tools that update existing "Class" objects in-place
* and need to make the Introspector re-analyze an existing Class object.
*
* Note that only the direct state associated with the target Class
* object is flushed. We do not flush state for other Class objects
* with the same name, nor do we flush state for any related Class
* objects (such as subclasses), even though their state may include
* information indirectly obtained from the target Class object.
*
* @param clz Class object to be flushed.
* @throws NullPointerException If the Class object is null.
*/
public static void flushFromCaches(Class<?> clz) {
if (clz == null) {
throw new NullPointerException();
}
beanInfoCache.remove(clz);
declaredMethodCache.remove(clz);
}
//======================================================================
// Private implementation methods
//======================================================================
private Introspector(Class beanClass, Class stopClass, int flags)
throws IntrospectionException {
this.beanClass = beanClass;
// Check stopClass is a superClass of startClass.
if (stopClass != null) {
boolean isSuper = false;
for (Class c = beanClass.getSuperclass(); c != null; c = c.getSuperclass()) {
if (c == stopClass) {
isSuper = true;
}
}
if (!isSuper) {
throw new IntrospectionException(stopClass.getName() + " not superclass of " +
beanClass.getName());
}
}
if (flags == USE_ALL_BEANINFO) {
explicitBeanInfo = findExplicitBeanInfo(beanClass);
}
Class superClass = beanClass.getSuperclass();
if (superClass != stopClass) {
int newFlags = flags;
if (newFlags == IGNORE_IMMEDIATE_BEANINFO) {
newFlags = USE_ALL_BEANINFO;
}
superBeanInfo = getBeanInfo(superClass, stopClass, newFlags);
}
if (explicitBeanInfo != null) {
additionalBeanInfo = explicitBeanInfo.getAdditionalBeanInfo();
}
if (additionalBeanInfo == null) {
additionalBeanInfo = new BeanInfo[0];
}
}
/**
* Constructs a GenericBeanInfo class from the state of the Introspector
*/
private BeanInfo getBeanInfo() throws IntrospectionException {
// the evaluation order here is import, as we evaluate the
// event sets and locate PropertyChangeListeners before we
// look for properties.
BeanDescriptor bd = getTargetBeanDescriptor();
MethodDescriptor mds[] = getTargetMethodInfo();
EventSetDescriptor esds[] = getTargetEventInfo();
PropertyDescriptor pds[] = getTargetPropertyInfo();
int defaultEvent = getTargetDefaultEventIndex();
int defaultProperty = getTargetDefaultPropertyIndex();
return new GenericBeanInfo(bd, esds, defaultEvent, pds,
defaultProperty, mds, explicitBeanInfo);
}
/**
* Looks for an explicit BeanInfo class that corresponds to the Class.
* First it looks in the existing package that the Class is defined in,
* then it checks to see if the class is its own BeanInfo. Finally,
* the BeanInfo search path is prepended to the class and searched.
*
* @return Instance of an explicit BeanInfo class or null if one isn't found.
*/
private static synchronized BeanInfo findExplicitBeanInfo(Class beanClass) {
String name = beanClass.getName() + BEANINFO_SUFFIX;
try {
return (java.beans.BeanInfo)instantiate(beanClass, name);
} catch (Exception ex) {
// Just drop through
}
// Now try checking if the bean is its own BeanInfo.
try {
if (isSubclass(beanClass, java.beans.BeanInfo.class)) {
return (java.beans.BeanInfo)beanClass.newInstance();
}
} catch (Exception ex) {
// Just drop through
}
// Now try looking for <searchPath>.fooBeanInfo
name = name.substring(name.lastIndexOf('.')+1);
for (int i = 0; i < searchPath.length; i++) {
// This optimization will only use the BeanInfo search path if is has changed
// from the original or trying to get the ComponentBeanInfo.
if (!DEFAULT_INFO_PATH.equals(searchPath[i]) ||
DEFAULT_INFO_PATH.equals(searchPath[i]) && "ComponentBeanInfo".equals(name)) {
try {
String fullName = searchPath[i] + "." + name;
java.beans.BeanInfo bi = (java.beans.BeanInfo)instantiate(beanClass, fullName);
// Make sure that the returned BeanInfo matches the class.
if (bi.getBeanDescriptor() != null) {
if (bi.getBeanDescriptor().getBeanClass() == beanClass) {
return bi;
}
} else if (bi.getPropertyDescriptors() != null) {
PropertyDescriptor[] pds = bi.getPropertyDescriptors();
for (int j = 0; j < pds.length; j++) {
Method method = pds[j].getReadMethod();
if (method == null) {
method = pds[j].getWriteMethod();
}
if (method != null && method.getDeclaringClass() == beanClass) {
return bi;
}
}
} else if (bi.getMethodDescriptors() != null) {
MethodDescriptor[] mds = bi.getMethodDescriptors();
for (int j = 0; j < mds.length; j++) {
Method method = mds[j].getMethod();
if (method != null && method.getDeclaringClass() == beanClass) {
return bi;
}
}
}
} catch (Exception ex) {
// Silently ignore any errors.
}
}
}
return null;
}
/**
* @return An array of PropertyDescriptors describing the editable
* properties supported by the target bean.
*/
private PropertyDescriptor[] getTargetPropertyInfo() {
// Check if the bean has its own BeanInfo that will provide
// explicit information.
PropertyDescriptor[] explicitProperties = null;
if (explicitBeanInfo != null) {
explicitProperties = explicitBeanInfo.getPropertyDescriptors();
int ix = explicitBeanInfo.getDefaultPropertyIndex();
if (ix >= 0 && ix < explicitProperties.length) {
defaultPropertyName = explicitProperties[ix].getName();
}
}
if (explicitProperties == null && superBeanInfo != null) {
// We have no explicit BeanInfo properties. Check with our parent.
PropertyDescriptor supers[] = superBeanInfo.getPropertyDescriptors();
for (int i = 0 ; i < supers.length; i++) {
addPropertyDescriptor(supers[i]);
}
int ix = superBeanInfo.getDefaultPropertyIndex();
if (ix >= 0 && ix < supers.length) {
defaultPropertyName = supers[ix].getName();
}
}
for (int i = 0; i < additionalBeanInfo.length; i++) {
PropertyDescriptor additional[] = additionalBeanInfo[i].getPropertyDescriptors();
if (additional != null) {
for (int j = 0 ; j < additional.length; j++) {
addPropertyDescriptor(additional[j]);
}
}
}
if (explicitProperties != null) {
// Add the explicit BeanInfo data to our results.
for (int i = 0 ; i < explicitProperties.length; i++) {
addPropertyDescriptor(explicitProperties[i]);
}
} else {
// Apply some reflection to the current class.
// First get an array of all the public methods at this level
Method methodList[] = getPublicDeclaredMethods(beanClass);
// Now analyze each method.
for (int i = 0; i < methodList.length; i++) {
Method method = methodList[i];
if (method == null) {
continue;
}
// skip static methods.
int mods = method.getModifiers();
if (Modifier.isStatic(mods)) {
continue;
}
String name = method.getName();
Class argTypes[] = method.getParameterTypes();
Class resultType = method.getReturnType();
int argCount = argTypes.length;
PropertyDescriptor pd = null;
if (name.length() <= 3 && !name.startsWith(IS_PREFIX)) {
// Optimization. Don't bother with invalid propertyNames.
continue;
}
try {
if (argCount == 0) {
if (name.startsWith(GET_PREFIX)) {
// Simple getter
pd = new PropertyDescriptor(decapitalize(name.substring(3)),
method, null);
} else if (resultType == boolean.class && name.startsWith(IS_PREFIX)) {
// Boolean getter
pd = new PropertyDescriptor(decapitalize(name.substring(2)),
method, null);
}
} else if (argCount == 1) {
if (argTypes[0] == int.class && name.startsWith(GET_PREFIX)) {
pd = new IndexedPropertyDescriptor(
decapitalize(name.substring(3)),
null, null,
method, null);
} else if (resultType == void.class && name.startsWith(SET_PREFIX)) {
// Simple setter
pd = new PropertyDescriptor(decapitalize(name.substring(3)),
null, method);
if (throwsException(method, PropertyVetoException.class)) {
pd.setConstrained(true);
}
}
} else if (argCount == 2) {
if (argTypes[0] == int.class && name.startsWith(SET_PREFIX)) {
pd = new IndexedPropertyDescriptor(
decapitalize(name.substring(3)),
null, null,
null, method);
if (throwsException(method, PropertyVetoException.class)) {
pd.setConstrained(true);
}
}
}
} catch (IntrospectionException ex) {
// This happens if a PropertyDescriptor or IndexedPropertyDescriptor
// constructor fins that the method violates details of the deisgn
// pattern, e.g. by having an empty name, or a getter returning
// void , or whatever.
pd = null;
}
if (pd != null) {
// If this class or one of its base classes is a PropertyChange
// source, then we assume that any properties we discover are "bound".
if (propertyChangeSource) {
pd.setBound(true);
}
addPropertyDescriptor(pd);
}
}
}
processPropertyDescriptors();
// Allocate and populate the result array.
PropertyDescriptor result[] = new PropertyDescriptor[properties.size()];
result = (PropertyDescriptor[])properties.values().toArray(result);
// Set the default index.
if (defaultPropertyName != null) {
for (int i = 0; i < result.length; i++) {
if (defaultPropertyName.equals(result[i].getName())) {
defaultPropertyIndex = i;
}
}
}
return result;
}
private HashMap pdStore = new HashMap();
/**
* Adds the property descriptor to the list store.
*/
private void addPropertyDescriptor(PropertyDescriptor pd) {
String propName = pd.getName();
List list = (List)pdStore.get(propName);
if (list == null) {
list = new ArrayList();
pdStore.put(propName, list);
}
list.add(pd);
}
/**
* Populates the property descriptor table by merging the
* lists of Property descriptors.
*/
private void processPropertyDescriptors() {
if (properties == null) {
properties = new TreeMap();
}
List list;
PropertyDescriptor pd, gpd, spd;
IndexedPropertyDescriptor ipd, igpd, ispd;
Iterator it = pdStore.values().iterator();
while (it.hasNext()) {
pd = null; gpd = null; spd = null;
ipd = null; igpd = null; ispd = null;
list = (List)it.next();
// First pass. Find the latest getter method. Merge properties
// of previous getter methods.
for (int i = 0; i < list.size(); i++) {
pd = (PropertyDescriptor)list.get(i);
if (pd instanceof IndexedPropertyDescriptor) {
ipd = (IndexedPropertyDescriptor)pd;
if (ipd.getIndexedReadMethod() != null) {
if (igpd != null) {
igpd = new IndexedPropertyDescriptor(igpd, ipd);
} else {
igpd = ipd;
}
}
} else {
if (pd.getReadMethod() != null) {
if (gpd != null) {
// Don't replace the existing read
// method if it starts with "is"
Method method = gpd.getReadMethod();
if (!method.getName().startsWith(IS_PREFIX)) {
gpd = new PropertyDescriptor(gpd, pd);
}
} else {
gpd = pd;
}
}
}
}
// Second pass. Find the latest setter method which
// has the same type as the getter method.
for (int i = 0; i < list.size(); i++) {
pd = (PropertyDescriptor)list.get(i);
if (pd instanceof IndexedPropertyDescriptor) {
ipd = (IndexedPropertyDescriptor)pd;
if (ipd.getIndexedWriteMethod() != null) {
if (igpd != null) {
if (igpd.getIndexedPropertyType()
== ipd.getIndexedPropertyType()) {
if (ispd != null) {
ispd = new IndexedPropertyDescriptor(ispd, ipd);
} else {
ispd = ipd;
}
}
} else {
if (ispd != null) {
ispd = new IndexedPropertyDescriptor(ispd, ipd);
} else {
ispd = ipd;
}
}
}
} else {
if (pd.getWriteMethod() != null) {
if (gpd != null) {
if (gpd.getPropertyType() == pd.getPropertyType()) {
if (spd != null) {
spd = new PropertyDescriptor(spd, pd);
} else {
spd = pd;
}
}
} else {
if (spd != null) {
spd = new PropertyDescriptor(spd, pd);
} else {
spd = pd;
}
}
}
}
}
// At this stage we should have either PDs or IPDs for the
// representative getters and setters. The order at which the
// property descriptors are determined represent the
// precedence of the property ordering.
pd = null; ipd = null;
if (igpd != null && ispd != null) {
// Complete indexed properties set
// Merge any classic property descriptors
if (gpd != null) {
PropertyDescriptor tpd = mergePropertyDescriptor(igpd, gpd);
if (tpd instanceof IndexedPropertyDescriptor) {
igpd = (IndexedPropertyDescriptor)tpd;
}
}
if (spd != null) {
PropertyDescriptor tpd = mergePropertyDescriptor(ispd, spd);
if (tpd instanceof IndexedPropertyDescriptor) {
ispd = (IndexedPropertyDescriptor)tpd;
}
}
if (igpd == ispd) {
pd = igpd;
} else {
pd = mergePropertyDescriptor(igpd, ispd);
}
} else if (gpd != null && spd != null) {
// Complete simple properties set
if (gpd == spd) {
pd = gpd;
} else {
pd = mergePropertyDescriptor(gpd, spd);
}
} else if (ispd != null) {
// indexed setter
pd = ispd;
// Merge any classic property descriptors
if (spd != null) {
pd = mergePropertyDescriptor(ispd, spd);
}
if (gpd != null) {
pd = mergePropertyDescriptor(ispd, gpd);
}
} else if (igpd != null) {
// indexed getter
pd = igpd;
// Merge any classic property descriptors
if (gpd != null) {
pd = mergePropertyDescriptor(igpd, gpd);
}
if (spd != null) {
pd = mergePropertyDescriptor(igpd, spd);
}
} else if (spd != null) {
// simple setter
pd = spd;
} else if (gpd != null) {
// simple getter
pd = gpd;
}
// Very special case to ensure that an IndexedPropertyDescriptor
// doesn't contain less information than the enclosed
// PropertyDescriptor. If it does, then recreate as a
// PropertyDescriptor. See 4168833
if (pd instanceof IndexedPropertyDescriptor) {
ipd = (IndexedPropertyDescriptor)pd;
if (ipd.getIndexedReadMethod() == null && ipd.getIndexedWriteMethod() == null) {
pd = new PropertyDescriptor(ipd);
}
}
// Find the first property descriptor
// which does not have getter and setter methods.
// See regression bug 4984912.
if ( (pd == null) && (list.size() > 0) ) {
pd = (PropertyDescriptor) list.get(0);
}
if (pd != null) {
properties.put(pd.getName(), pd);
}
}
}
/**
* Adds the property descriptor to the indexedproperty descriptor only if the
* types are the same.
*
* The most specific property descriptor will take precedence.
*/
private PropertyDescriptor mergePropertyDescriptor(IndexedPropertyDescriptor ipd,
PropertyDescriptor pd) {
PropertyDescriptor result = null;
Class propType = pd.getPropertyType();
Class ipropType = ipd.getIndexedPropertyType();
if (propType.isArray() && propType.getComponentType() == ipropType) {
if (pd.getClass0().isAssignableFrom(ipd.getClass0())) {
result = new IndexedPropertyDescriptor(pd, ipd);
} else {
result = new IndexedPropertyDescriptor(ipd, pd);
}
} else {
// Cannot merge the pd because of type mismatch
// Return the most specific pd
if (pd.getClass0().isAssignableFrom(ipd.getClass0())) {
result = ipd;
} else {
result = pd;
// Try to add methods which may have been lost in the type change
// See 4168833
Method write = result.getWriteMethod();
Method read = result.getReadMethod();
if (read == null && write != null) {
read = findMethod(result.getClass0(),
"get" + result.capitalize(result.getName()), 0);
if (read != null) {
try {
result.setReadMethod(read);
} catch (IntrospectionException ex) {
// no consequences for failure.
}
}
}
if (write == null && read != null) {
write = findMethod(result.getClass0(),
"set" + result.capitalize(result.getName()), 1,
new Class[] { read.getReturnType() });
if (write != null) {
try {
result.setWriteMethod(write);
} catch (IntrospectionException ex) {
// no consequences for failure.
}
}
}
}
}
return result;
}
// Handle regular pd merge
private PropertyDescriptor mergePropertyDescriptor(PropertyDescriptor pd1,
PropertyDescriptor pd2) {
if (pd1.getClass0().isAssignableFrom(pd2.getClass0())) {
return new PropertyDescriptor(pd1, pd2);
} else {
return new PropertyDescriptor(pd2, pd1);
}
}
// Handle regular ipd merge
private PropertyDescriptor mergePropertyDescriptor(IndexedPropertyDescriptor ipd1,
IndexedPropertyDescriptor ipd2) {
if (ipd1.getClass0().isAssignableFrom(ipd2.getClass0())) {
return new IndexedPropertyDescriptor(ipd1, ipd2);
} else {
return new IndexedPropertyDescriptor(ipd2, ipd1);
}
}
/**
* @return An array of EventSetDescriptors describing the kinds of
* events fired by the target bean.
*/
private EventSetDescriptor[] getTargetEventInfo() throws IntrospectionException {
if (events == null) {
events = new HashMap();
}
// Check if the bean has its own BeanInfo that will provide
// explicit information.
EventSetDescriptor[] explicitEvents = null;
if (explicitBeanInfo != null) {
explicitEvents = explicitBeanInfo.getEventSetDescriptors();
int ix = explicitBeanInfo.getDefaultEventIndex();
if (ix >= 0 && ix < explicitEvents.length) {
defaultEventName = explicitEvents[ix].getName();
}
}
if (explicitEvents == null && superBeanInfo != null) {
// We have no explicit BeanInfo events. Check with our parent.
EventSetDescriptor supers[] = superBeanInfo.getEventSetDescriptors();
for (int i = 0 ; i < supers.length; i++) {
addEvent(supers[i]);
}
int ix = superBeanInfo.getDefaultEventIndex();
if (ix >= 0 && ix < supers.length) {
defaultEventName = supers[ix].getName();
}
}
for (int i = 0; i < additionalBeanInfo.length; i++) {
EventSetDescriptor additional[] = additionalBeanInfo[i].getEventSetDescriptors();
if (additional != null) {
for (int j = 0 ; j < additional.length; j++) {
addEvent(additional[j]);
}
}
}
if (explicitEvents != null) {
// Add the explicit explicitBeanInfo data to our results.
for (int i = 0 ; i < explicitEvents.length; i++) {
addEvent(explicitEvents[i]);
}
} else {
// Apply some reflection to the current class.
// Get an array of all the public beans methods at this level
Method methodList[] = getPublicDeclaredMethods(beanClass);
// Find all suitable "add", "remove" and "get" Listener methods
// The name of the listener type is the key for these hashtables
// i.e, ActionListener
Map adds = null;
Map removes = null;
Map gets = null;
for (int i = 0; i < methodList.length; i++) {
Method method = methodList[i];
if (method == null) {
continue;
}
// skip static methods.
int mods = method.getModifiers();
if (Modifier.isStatic(mods)) {
continue;
}
String name = method.getName();
// Optimization avoid getParameterTypes
if (!name.startsWith(ADD_PREFIX) && !name.startsWith(REMOVE_PREFIX)
&& !name.startsWith(GET_PREFIX)) {
continue;
}
Class argTypes[] = method.getParameterTypes();
Class resultType = method.getReturnType();
if (name.startsWith(ADD_PREFIX) && argTypes.length == 1 &&
resultType == Void.TYPE &&
Introspector.isSubclass(argTypes[0], eventListenerType)) {
String listenerName = name.substring(3);
if (listenerName.length() > 0 &&
argTypes[0].getName().endsWith(listenerName)) {
if (adds == null) {
adds = new HashMap();
}
adds.put(listenerName, method);
}
}
else if (name.startsWith(REMOVE_PREFIX) && argTypes.length == 1 &&
resultType == Void.TYPE &&
Introspector.isSubclass(argTypes[0], eventListenerType)) {
String listenerName = name.substring(6);
if (listenerName.length() > 0 &&
argTypes[0].getName().endsWith(listenerName)) {
if (removes == null) {
removes = new HashMap();
}
removes.put(listenerName, method);
}
}
else if (name.startsWith(GET_PREFIX) && argTypes.length == 0 &&
resultType.isArray() &&
Introspector.isSubclass(resultType.getComponentType(),
eventListenerType)) {
String listenerName = name.substring(3, name.length() - 1);
if (listenerName.length() > 0 &&
resultType.getComponentType().getName().endsWith(listenerName)) {
if (gets == null) {
gets = new HashMap();
}
gets.put(listenerName, method);
}
}
}
if (adds != null && removes != null) {
// Now look for matching addFooListener+removeFooListener pairs.
// Bonus if there is a matching getFooListeners method as well.
Iterator keys = adds.keySet().iterator();
while (keys.hasNext()) {
String listenerName = (String) keys.next();
// Skip any "add" which doesn't have a matching "remove" or
// a listener name that doesn't end with Listener
if (removes.get(listenerName) == null || !listenerName.endsWith("Listener")) {
continue;
}
String eventName = decapitalize(listenerName.substring(0, listenerName.length()-8));
Method addMethod = (Method)adds.get(listenerName);
Method removeMethod = (Method)removes.get(listenerName);
Method getMethod = null;
if (gets != null) {
getMethod = (Method)gets.get(listenerName);
}
Class argType = addMethod.getParameterTypes()[0];
// generate a list of Method objects for each of the target methods:
Method allMethods[] = getPublicDeclaredMethods(argType);
List validMethods = new ArrayList(allMethods.length);
for (int i = 0; i < allMethods.length; i++) {
if (allMethods[i] == null) {
continue;
}
if (isEventHandler(allMethods[i])) {
validMethods.add(allMethods[i]);
}
}
Method[] methods = (Method[])validMethods.toArray(new Method[validMethods.size()]);
EventSetDescriptor esd = new EventSetDescriptor(eventName, argType,
methods, addMethod,
removeMethod,
getMethod);
// If the adder method throws the TooManyListenersException then it
// is a Unicast event source.
if (throwsException(addMethod,
java.util.TooManyListenersException.class)) {
esd.setUnicast(true);
}
addEvent(esd);
}
} // if (adds != null ...
}
EventSetDescriptor[] result;
if (events.size() == 0) {
result = EMPTY_EVENTSETDESCRIPTORS;
} else {
// Allocate and populate the result array.
result = new EventSetDescriptor[events.size()];
result = (EventSetDescriptor[])events.values().toArray(result);
// Set the default index.
if (defaultEventName != null) {
for (int i = 0; i < result.length; i++) {
if (defaultEventName.equals(result[i].getName())) {
defaultEventIndex = i;
}
}
}
}
return result;
}
private void addEvent(EventSetDescriptor esd) {
String key = esd.getName();
if (esd.getName().equals("propertyChange")) {
propertyChangeSource = true;
}
EventSetDescriptor old = (EventSetDescriptor)events.get(key);
if (old == null) {
events.put(key, esd);
return;
}
EventSetDescriptor composite = new EventSetDescriptor(old, esd);
events.put(key, composite);
}
/**
* @return An array of MethodDescriptors describing the private
* methods supported by the target bean.
*/
private MethodDescriptor[] getTargetMethodInfo() {
if (methods == null) {
methods = new HashMap(100);
}
// Check if the bean has its own BeanInfo that will provide
// explicit information.
MethodDescriptor[] explicitMethods = null;
if (explicitBeanInfo != null) {
explicitMethods = explicitBeanInfo.getMethodDescriptors();
}
if (explicitMethods == null && superBeanInfo != null) {
// We have no explicit BeanInfo methods. Check with our parent.
MethodDescriptor supers[] = superBeanInfo.getMethodDescriptors();
for (int i = 0 ; i < supers.length; i++) {
addMethod(supers[i]);
}
}
for (int i = 0; i < additionalBeanInfo.length; i++) {
MethodDescriptor additional[] = additionalBeanInfo[i].getMethodDescriptors();
if (additional != null) {
for (int j = 0 ; j < additional.length; j++) {
addMethod(additional[j]);
}
}
}
if (explicitMethods != null) {
// Add the explicit explicitBeanInfo data to our results.
for (int i = 0 ; i < explicitMethods.length; i++) {
addMethod(explicitMethods[i]);
}
} else {
// Apply some reflection to the current class.
// First get an array of all the beans methods at this level
Method methodList[] = getPublicDeclaredMethods(beanClass);
// Now analyze each method.
for (int i = 0; i < methodList.length; i++) {
Method method = methodList[i];
if (method == null) {
continue;
}
MethodDescriptor md = new MethodDescriptor(method);
addMethod(md);
}
}
// Allocate and populate the result array.
MethodDescriptor result[] = new MethodDescriptor[methods.size()];
result = (MethodDescriptor[])methods.values().toArray(result);
return result;
}
private void addMethod(MethodDescriptor md) {
// We have to be careful here to distinguish method by both name
// and argument lists.
// This method gets called a *lot, so we try to be efficient.
String name = md.getName();
MethodDescriptor old = (MethodDescriptor)methods.get(name);
if (old == null) {
// This is the common case.
methods.put(name, md);
return;
}
// We have a collision on method names. This is rare.
// Check if old and md have the same type.
String[] p1 = md.getParamNames();
String[] p2 = old.getParamNames();
boolean match = false;
if (p1.length == p2.length) {
match = true;
for (int i = 0; i < p1.length; i++) {
if (p1[i] != p2[i]) {
match = false;
break;
}
}
}
if (match) {
MethodDescriptor composite = new MethodDescriptor(old, md);
methods.put(name, composite);
return;
}
// We have a collision on method names with different type signatures.
// This is very rare.
String longKey = makeQualifiedMethodName(name, p1);
old = (MethodDescriptor)methods.get(longKey);
if (old == null) {
methods.put(longKey, md);
return;
}
MethodDescriptor composite = new MethodDescriptor(old, md);
methods.put(longKey, composite);
}
/**
* Creates a key for a method in a method cache.
*/
private static String makeQualifiedMethodName(String name, String[] params) {
StringBuffer sb = new StringBuffer(name);
sb.append('=');
for (int i = 0; i < params.length; i++) {
sb.append(':');
sb.append(params[i]);
}
return sb.toString();
}
private int getTargetDefaultEventIndex() {
return defaultEventIndex;
}
private int getTargetDefaultPropertyIndex() {
return defaultPropertyIndex;
}
private BeanDescriptor getTargetBeanDescriptor() {
// Use explicit info, if available,
if (explicitBeanInfo != null) {
BeanDescriptor bd = explicitBeanInfo.getBeanDescriptor();
if (bd != null) {
return (bd);
}
}
// OK, fabricate a default BeanDescriptor.
return (new BeanDescriptor(beanClass));
}
private boolean isEventHandler(Method m) {
// We assume that a method is an event handler if it has a single
// argument, whose type inherit from java.util.Event.
Class argTypes[] = m.getParameterTypes();
if (argTypes.length != 1) {
return false;
}
if (isSubclass(argTypes[0], java.util.EventObject.class)) {
return true;
}
return false;
}
/*
* Internal method to return *public* methods within a class.
*/
private static synchronized Method[] getPublicDeclaredMethods(Class clz) {
// Looking up Class.getDeclaredMethods is relatively expensive,
// so we cache the results.
Method[] result = null;
if (!ReflectUtil.isPackageAccessible(clz)) {
return new Method[0];
}
final Class fclz = clz;
Reference ref = (Reference)declaredMethodCache.get(fclz);
if (ref != null) {
result = (Method[])ref.get();
if (result != null) {
return result;
}
}
// We have to raise privilege for getDeclaredMethods
result = (Method[]) AccessController.doPrivileged(new PrivilegedAction() {
public Object run() {
return fclz.getDeclaredMethods();
}
});
// Null out any non-public methods.
for (int i = 0; i < result.length; i++) {
Method method = result[i];
int mods = method.getModifiers();
if (!Modifier.isPublic(mods)) {
result[i] = null;
}
}
// Add it to the cache.
declaredMethodCache.put(fclz, new SoftReference(result));
return result;
}
//======================================================================
// Package private support methods.
//======================================================================
/**
* Internal support for finding a target methodName with a given
* parameter list on a given class.
*/
private static Method internalFindMethod(Class start, String methodName,
int argCount, Class args[]) {
// For overriden methods we need to find the most derived version.
// So we start with the given class and walk up the superclass chain.
Method method = null;
for (Class cl = start; cl != null; cl = cl.getSuperclass()) {
Method methods[] = getPublicDeclaredMethods(cl);
for (int i = 0; i < methods.length; i++) {
method = methods[i];
if (method == null) {
continue;
}
// make sure method signature matches.
Class params[] = method.getParameterTypes();
if (method.getName().equals(methodName) &&
params.length == argCount) {
if (args != null) {
boolean different = false;
if (argCount > 0) {
for (int j = 0; j < argCount; j++) {
if (params[j] != args[j]) {
different = true;
continue;
}
}
if (different) {
continue;
}
}
}
return method;
}
}
}
method = null;
// Now check any inherited interfaces. This is necessary both when
// the argument class is itself an interface, and when the argument
// class is an abstract class.
Class ifcs[] = start.getInterfaces();
for (int i = 0 ; i < ifcs.length; i++) {
// Note: The original implementation had both methods calling
// the 3 arg method. This is preserved but perhaps it should
// pass the args array instead of null.
method = internalFindMethod(ifcs[i], methodName, argCount, null);
if (method != null) {
break;
}
}
return method;
}
/**
* Find a target methodName on a given class.
*/
static Method findMethod(Class cls, String methodName, int argCount) {
return findMethod(cls, methodName, argCount, null);
}
/**
* Find a target methodName with specific parameter list on a given class.
* <p>
* Used in the contructors of the EventSetDescriptor,
* PropertyDescriptor and the IndexedPropertyDescriptor.
* <p>
* @param cls The Class object on which to retrieve the method.
* @param methodName Name of the method.
* @param argCount Number of arguments for the desired method.
* @param args Array of argument types for the method.
* @return the method or null if not found
*/
static Method findMethod(Class cls, String methodName, int argCount,
Class args[]) {
if (methodName == null) {
return null;
}
return internalFindMethod(cls, methodName, argCount, args);
}
/**
* Return true if class a is either equivalent to class b, or
* if class a is a subclass of class b, i.e. if a either "extends"
* or "implements" b.
* Note tht either or both "Class" objects may represent interfaces.
*/
static boolean isSubclass(Class a, Class b) {
// We rely on the fact that for any given java class or
// primtitive type there is a unqiue Class object, so
// we can use object equivalence in the comparisons.
if (a == b) {
return true;
}
if (a == null || b == null) {
return false;
}
for (Class x = a; x != null; x = x.getSuperclass()) {
if (x == b) {
return true;
}
if (b.isInterface()) {
Class interfaces[] = x.getInterfaces();
for (int i = 0; i < interfaces.length; i++) {
if (isSubclass(interfaces[i], b)) {
return true;
}
}
}
}
return false;
}
/**
* Return true iff the given method throws the given exception.
*/
private boolean throwsException(Method method, Class exception) {
Class exs[] = method.getExceptionTypes();
for (int i = 0; i < exs.length; i++) {
if (exs[i] == exception) {
return true;
}
}
return false;
}
/**
* Try to create an instance of a named class.
* First try the classloader of "sibling", then try the system
* classloader then the class loader of the current Thread.
*/
static Object instantiate(Class sibling, String className)
throws InstantiationException, IllegalAccessException,
ClassNotFoundException {
// First check with sibling's classloader (if any).
ClassLoader cl = sibling.getClassLoader();
if (cl != null) {
try {
Class cls = cl.loadClass(className);
return cls.newInstance();
} catch (Exception ex) {
// Just drop through and try the system classloader.
}
}
// Now try the system classloader.
try {
cl = ClassLoader.getSystemClassLoader();
if (cl != null) {
Class cls = cl.loadClass(className);
return cls.newInstance();
}
} catch (Exception ex) {
// We're not allowed to access the system class loader or
// the class creation failed.
// Drop through.
}
// Use the classloader from the current Thread.
cl = Thread.currentThread().getContextClassLoader();
Class cls = cl.loadClass(className);
return cls.newInstance();
}
} // end class Introspector
//===========================================================================
/**
* Package private implementation support class for Introspector's
* internal use.
* <p>
* Mostly this is used as a placeholder for the descriptors.
*/
class GenericBeanInfo extends SimpleBeanInfo {
private BeanDescriptor beanDescriptor;
private EventSetDescriptor[] events;
private int defaultEvent;
private PropertyDescriptor[] properties;
private int defaultProperty;
private MethodDescriptor[] methods;
private BeanInfo targetBeanInfo;
public GenericBeanInfo(BeanDescriptor beanDescriptor,
EventSetDescriptor[] events, int defaultEvent,
PropertyDescriptor[] properties, int defaultProperty,
MethodDescriptor[] methods, BeanInfo targetBeanInfo) {
this.beanDescriptor = beanDescriptor;
this.events = events;
this.defaultEvent = defaultEvent;
this.properties = properties;
this.defaultProperty = defaultProperty;
this.methods = methods;
this.targetBeanInfo = targetBeanInfo;
}
/**
* Package-private dup constructor
* This must isolate the new object from any changes to the old object.
*/
GenericBeanInfo(GenericBeanInfo old) {
beanDescriptor = new BeanDescriptor(old.beanDescriptor);
if (old.events != null) {
int len = old.events.length;
events = new EventSetDescriptor[len];
for (int i = 0; i < len; i++) {
events[i] = new EventSetDescriptor(old.events[i]);
}
}
defaultEvent = old.defaultEvent;
if (old.properties != null) {
int len = old.properties.length;
properties = new PropertyDescriptor[len];
for (int i = 0; i < len; i++) {
PropertyDescriptor oldp = old.properties[i];
if (oldp instanceof IndexedPropertyDescriptor) {
properties[i] = new IndexedPropertyDescriptor(
(IndexedPropertyDescriptor) oldp);
} else {
properties[i] = new PropertyDescriptor(oldp);
}
}
}
defaultProperty = old.defaultProperty;
if (old.methods != null) {
int len = old.methods.length;
methods = new MethodDescriptor[len];
for (int i = 0; i < len; i++) {
methods[i] = new MethodDescriptor(old.methods[i]);
}
}
targetBeanInfo = old.targetBeanInfo;
}
public PropertyDescriptor[] getPropertyDescriptors() {
return properties;
}
public int getDefaultPropertyIndex() {
return defaultProperty;
}
public EventSetDescriptor[] getEventSetDescriptors() {
return events;
}
public int getDefaultEventIndex() {
return defaultEvent;
}
public MethodDescriptor[] getMethodDescriptors() {
return methods;
}
public BeanDescriptor getBeanDescriptor() {
return beanDescriptor;
}
public java.awt.Image getIcon(int iconKind) {
if (targetBeanInfo != null) {
return targetBeanInfo.getIcon(iconKind);
}
return super.getIcon(iconKind);
}
}
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