/*
* Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package java.beans.beancontext;
import java.awt.Component;
import java.awt.Container;
import java.beans.Beans;
import java.beans.AppletInitializer;
import java.beans.DesignMode;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.beans.VetoableChangeListener;
import java.beans.VetoableChangeSupport;
import java.beans.PropertyVetoException;
import java.beans.Visibility;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.net.URL;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Locale;
import java.util.Map;
/**
* This helper class provides a utility implementation of the
* java.beans.beancontext.BeanContext interface.
* <p>
* Since this class directly implements the BeanContext interface, the class
* can, and is intended to be used either by subclassing this implementation,
* or via ad-hoc delegation of an instance of this class from another.
* </p>
*
* @author Laurence P. G. Cable
* @since 1.2
*/
public class BeanContextSupport extends BeanContextChildSupport
implements BeanContext,
Serializable,
PropertyChangeListener,
VetoableChangeListener {
// Fix for bug 4282900 to pass JCK regression test
static final long serialVersionUID = -4879613978649577204L;
/**
*
* Construct a BeanContextSupport instance
*
*
* @param peer The peer {@code BeanContext} we are
* supplying an implementation for,
* or {@code null}
* if this object is its own peer
* @param lcle The current Locale for this BeanContext. If
* {@code lcle} is {@code null}, the default locale
* is assigned to the {@code BeanContext} instance.
* @param dTime The initial state,
* {@code true} if in design mode,
* {@code false} if runtime.
* @param visible The initial visibility.
* @see java.util.Locale#getDefault()
* @see java.util.Locale#setDefault(java.util.Locale)
*/
public BeanContextSupport(BeanContext peer, Locale lcle, boolean dTime, boolean visible) {
super(peer);
locale = lcle != null ? lcle : Locale.getDefault();
designTime = dTime;
okToUseGui = visible;
initialize();
}
/**
* Create an instance using the specified Locale and design mode.
*
* @param peer The peer {@code BeanContext} we
* are supplying an implementation for,
* or {@code null} if this object is its own peer
* @param lcle The current Locale for this {@code BeanContext}. If
* {@code lcle} is {@code null}, the default locale
* is assigned to the {@code BeanContext} instance.
* @param dtime The initial state, {@code true}
* if in design mode,
* {@code false} if runtime.
* @see java.util.Locale#getDefault()
* @see java.util.Locale#setDefault(java.util.Locale)
*/
public BeanContextSupport(BeanContext peer, Locale lcle, boolean dtime) {
this (peer, lcle, dtime, true);
}
/**
* Create an instance using the specified locale
*
* @param peer The peer BeanContext we are
* supplying an implementation for,
* or {@code null} if this object
* is its own peer
* @param lcle The current Locale for this
* {@code BeanContext}. If
* {@code lcle} is {@code null},
* the default locale
* is assigned to the {@code BeanContext}
* instance.
* @see java.util.Locale#getDefault()
* @see java.util.Locale#setDefault(java.util.Locale)
*/
public BeanContextSupport(BeanContext peer, Locale lcle) {
this (peer, lcle, false, true);
}
/**
* Create an instance using with a default locale
*
* @param peer The peer {@code BeanContext} we are
* supplying an implementation for,
* or {@code null} if this object
* is its own peer
*/
public BeanContextSupport(BeanContext peer) {
this (peer, null, false, true);
}
/**
* Create an instance that is not a delegate of another object
*/
public BeanContextSupport() {
this (null, null, false, true);
}
/**
* Gets the instance of {@code BeanContext} that
* this object is providing the implementation for.
* @return the BeanContext instance
*/
public BeanContext getBeanContextPeer() { return (BeanContext)getBeanContextChildPeer(); }
/**
* <p>
* The instantiateChild method is a convenience hook
* in BeanContext to simplify
* the task of instantiating a Bean, nested,
* into a {@code BeanContext}.
* </p>
* <p>
* The semantics of the beanName parameter are defined by java.beans.Beans.instantiate.
* </p>
*
* @param beanName the name of the Bean to instantiate within this BeanContext
* @throws IOException if there is an I/O error when the bean is being deserialized
* @throws ClassNotFoundException if the class
* identified by the beanName parameter is not found
* @return the new object
*/
public Object instantiateChild(String beanName)
throws IOException, ClassNotFoundException {
BeanContext bc = getBeanContextPeer();
return Beans.instantiate(bc.getClass().getClassLoader(), beanName, bc);
}
/**
* Gets the number of children currently nested in
* this BeanContext.
*
* @return number of children
*/
public int size() {
synchronized(children) {
return children.size();
}
}
/**
* Reports whether or not this
* {@code BeanContext} is empty.
* A {@code BeanContext} is considered
* empty when it contains zero
* nested children.
* @return if there are not children
*/
public boolean isEmpty() {
synchronized(children) {
return children.isEmpty();
}
}
/**
* Determines whether or not the specified object
* is currently a child of this {@code BeanContext}.
* @param o the Object in question
* @return if this object is a child
*/
public boolean contains(Object o) {
synchronized(children) {
return children.containsKey(o);
}
}
/**
* Determines whether or not the specified object
* is currently a child of this {@code BeanContext}.
* @param o the Object in question
* @return if this object is a child
*/
public boolean containsKey(Object o) {
synchronized(children) {
return children.containsKey(o);
}
}
/**
* Gets all JavaBean or {@code BeanContext} instances
* currently nested in this {@code BeanContext}.
* @return an {@code Iterator} of the nested children
*/
public Iterator<Object> iterator() {
synchronized(children) {
return new BCSIterator(children.keySet().iterator());
}
}
/**
* Gets all JavaBean or {@code BeanContext}
* instances currently nested in this BeanContext.
*/
public Object[] toArray() {
synchronized(children) {
return children.keySet().toArray();
}
}
/**
* Gets an array containing all children of
* this {@code BeanContext} that match
* the types contained in arry.
* @param arry The array of object
* types that are of interest.
* @return an array of children
*/
public Object[] toArray(Object[] arry) {
synchronized(children) {
return children.keySet().toArray(arry);
}
}
/************************************************************************/
/**
* protected final subclass that encapsulates an iterator but implements
* a noop remove() method.
*/
protected static final class BCSIterator implements Iterator<Object> {
BCSIterator(Iterator<?> i) { super(); src = i; }
public boolean hasNext() { return src.hasNext(); }
public Object next() { return src.next(); }
public void remove() { /* do nothing */ }
private Iterator<?> src;
}
/************************************************************************/
/*
* protected nested class containing per child information, an instance
* of which is associated with each child in the "children" hashtable.
* subclasses can extend this class to include their own per-child state.
*
* Note that this 'value' is serialized with the corresponding child 'key'
* when the BeanContextSupport is serialized.
*/
protected class BCSChild implements Serializable {
private static final long serialVersionUID = -5815286101609939109L;
BCSChild(Object bcc, Object peer) {
super();
child = bcc;
proxyPeer = peer;
}
Object getChild() { return child; }
void setRemovePending(boolean v) { removePending = v; }
boolean isRemovePending() { return removePending; }
boolean isProxyPeer() { return proxyPeer != null; }
Object getProxyPeer() { return proxyPeer; }
/*
* fields
*/
private Object child;
private Object proxyPeer;
private transient boolean removePending;
}
/**
* <p>
* Subclasses can override this method to insert their own subclass
* of Child without having to override add() or the other Collection
* methods that add children to the set.
* </p>
* @param targetChild the child to create the Child on behalf of
* @param peer the peer if the tragetChild and the peer are related by an implementation of BeanContextProxy
* @return Subtype-specific subclass of Child without overriding collection methods
*/
protected BCSChild createBCSChild(Object targetChild, Object peer) {
return new BCSChild(targetChild, peer);
}
/************************************************************************/
/**
* Adds/nests a child within this {@code BeanContext}.
* <p>
* Invoked as a side effect of java.beans.Beans.instantiate().
* If the child object is not valid for adding then this method
* throws an IllegalStateException.
* </p>
*
*
* @param targetChild The child objects to nest
* within this {@code BeanContext}
* @return true if the child was added successfully.
* @see #validatePendingAdd
*/
public boolean add(Object targetChild) {
if (targetChild == null) throw new IllegalArgumentException();
// The specification requires that we do nothing if the child
// is already nested herein.
if (children.containsKey(targetChild)) return false; // test before locking
synchronized(BeanContext.globalHierarchyLock) {
if (children.containsKey(targetChild)) return false; // check again
if (!validatePendingAdd(targetChild)) {
throw new IllegalStateException();
}
// The specification requires that we invoke setBeanContext() on the
// newly added child if it implements the java.beans.beancontext.BeanContextChild interface
BeanContextChild cbcc = getChildBeanContextChild(targetChild);
BeanContextChild bccp = null;
synchronized(targetChild) {
if (targetChild instanceof BeanContextProxy) {
bccp = ((BeanContextProxy)targetChild).getBeanContextProxy();
if (bccp == null) throw new NullPointerException("BeanContextPeer.getBeanContextProxy()");
}
BCSChild bcsc = createBCSChild(targetChild, bccp);
BCSChild pbcsc = null;
synchronized (children) {
children.put(targetChild, bcsc);
if (bccp != null) children.put(bccp, pbcsc = createBCSChild(bccp, targetChild));
}
if (cbcc != null) synchronized(cbcc) {
try {
cbcc.setBeanContext(getBeanContextPeer());
} catch (PropertyVetoException pve) {
synchronized (children) {
children.remove(targetChild);
if (bccp != null) children.remove(bccp);
}
throw new IllegalStateException();
}
cbcc.addPropertyChangeListener("beanContext", childPCL);
cbcc.addVetoableChangeListener("beanContext", childVCL);
}
Visibility v = getChildVisibility(targetChild);
if (v != null) {
if (okToUseGui)
v.okToUseGui();
else
v.dontUseGui();
}
if (getChildSerializable(targetChild) != null) serializable++;
childJustAddedHook(targetChild, bcsc);
if (bccp != null) {
v = getChildVisibility(bccp);
if (v != null) {
if (okToUseGui)
v.okToUseGui();
else
v.dontUseGui();
}
if (getChildSerializable(bccp) != null) serializable++;
childJustAddedHook(bccp, pbcsc);
}
}
// The specification requires that we fire a notification of the change
fireChildrenAdded(new BeanContextMembershipEvent(getBeanContextPeer(), bccp == null ? new Object[] { targetChild } : new Object[] { targetChild, bccp } ));
}
return true;
}
/**
* Removes a child from this BeanContext. If the child object is not
* for adding then this method throws an IllegalStateException.
* @param targetChild The child objects to remove
* @see #validatePendingRemove
*/
public boolean remove(Object targetChild) {
return remove(targetChild, true);
}
/**
* internal remove used when removal caused by
* unexpected {@code setBeanContext} or
* by {@code remove()} invocation.
* @param targetChild the JavaBean, BeanContext, or Object to be removed
* @param callChildSetBC used to indicate that
* the child should be notified that it is no
* longer nested in this {@code BeanContext}.
* @return whether or not was present before being removed
*/
protected boolean remove(Object targetChild, boolean callChildSetBC) {
if (targetChild == null) throw new IllegalArgumentException();
synchronized(BeanContext.globalHierarchyLock) {
if (!containsKey(targetChild)) return false;
if (!validatePendingRemove(targetChild)) {
throw new IllegalStateException();
}
BCSChild bcsc = children.get(targetChild);
BCSChild pbcsc = null;
Object peer = null;
// we are required to notify the child that it is no longer nested here if
// it implements java.beans.beancontext.BeanContextChild
synchronized(targetChild) {
if (callChildSetBC) {
BeanContextChild cbcc = getChildBeanContextChild(targetChild);
if (cbcc != null) synchronized(cbcc) {
cbcc.removePropertyChangeListener("beanContext", childPCL);
cbcc.removeVetoableChangeListener("beanContext", childVCL);
try {
cbcc.setBeanContext(null);
} catch (PropertyVetoException pve1) {
cbcc.addPropertyChangeListener("beanContext", childPCL);
cbcc.addVetoableChangeListener("beanContext", childVCL);
throw new IllegalStateException();
}
}
}
synchronized (children) {
children.remove(targetChild);
if (bcsc.isProxyPeer()) {
pbcsc = children.get(peer = bcsc.getProxyPeer());
children.remove(peer);
}
}
if (getChildSerializable(targetChild) != null) serializable--;
childJustRemovedHook(targetChild, bcsc);
if (peer != null) {
if (getChildSerializable(peer) != null) serializable--;
childJustRemovedHook(peer, pbcsc);
}
}
fireChildrenRemoved(new BeanContextMembershipEvent(getBeanContextPeer(), peer == null ? new Object[] { targetChild } : new Object[] { targetChild, peer } ));
}
return true;
}
/**
* Tests to see if all objects in the
* specified {@code Collection} are children of
* this {@code BeanContext}.
* @param c the specified {@code Collection}
*
* @return {@code true} if all objects
* in the collection are children of
* this {@code BeanContext}, false if not.
*/
@SuppressWarnings("rawtypes")
public boolean containsAll(Collection c) {
synchronized(children) {
Iterator<?> i = c.iterator();
while (i.hasNext())
if(!contains(i.next()))
return false;
return true;
}
}
/**
* add Collection to set of Children (Unsupported)
* implementations must synchronized on the hierarchy lock and "children" protected field
* @throws UnsupportedOperationException thrown unconditionally by this implementation
* @return this implementation unconditionally throws {@code UnsupportedOperationException}
*/
@SuppressWarnings("rawtypes")
public boolean addAll(Collection c) {
throw new UnsupportedOperationException();
}
/**
* remove all specified children (Unsupported)
* implementations must synchronized on the hierarchy lock and "children" protected field
* @throws UnsupportedOperationException thrown unconditionally by this implementation
* @return this implementation unconditionally throws {@code UnsupportedOperationException}
*/
@SuppressWarnings("rawtypes")
public boolean removeAll(Collection c) {
throw new UnsupportedOperationException();
}
/**
* retain only specified children (Unsupported)
* implementations must synchronized on the hierarchy lock and "children" protected field
* @throws UnsupportedOperationException thrown unconditionally by this implementation
* @return this implementation unconditionally throws {@code UnsupportedOperationException}
*/
@SuppressWarnings("rawtypes")
public boolean retainAll(Collection c) {
throw new UnsupportedOperationException();
}
/**
* clear the children (Unsupported)
* implementations must synchronized on the hierarchy lock and "children" protected field
* @throws UnsupportedOperationException thrown unconditionally by this implementation
*/
public void clear() {
throw new UnsupportedOperationException();
}
/**
* Adds a BeanContextMembershipListener
*
* @param bcml the BeanContextMembershipListener to add
* @throws NullPointerException if the argument is null
*/
public void addBeanContextMembershipListener(BeanContextMembershipListener bcml) {
if (bcml == null) throw new NullPointerException("listener");
synchronized(bcmListeners) {
if (bcmListeners.contains(bcml))
return;
else
bcmListeners.add(bcml);
}
}
/**
* Removes a BeanContextMembershipListener
*
* @param bcml the BeanContextMembershipListener to remove
* @throws NullPointerException if the argument is null
*/
public void removeBeanContextMembershipListener(BeanContextMembershipListener bcml) {
if (bcml == null) throw new NullPointerException("listener");
synchronized(bcmListeners) {
if (!bcmListeners.contains(bcml))
return;
else
bcmListeners.remove(bcml);
}
}
/**
* @param name the name of the resource requested.
* @param bcc the child object making the request.
*
* @return the requested resource as an InputStream
* @throws NullPointerException if the argument is null
*/
public InputStream getResourceAsStream(String name, BeanContextChild bcc) {
if (name == null) throw new NullPointerException("name");
if (bcc == null) throw new NullPointerException("bcc");
if (containsKey(bcc)) {
ClassLoader cl = bcc.getClass().getClassLoader();
return cl != null ? cl.getResourceAsStream(name)
: ClassLoader.getSystemResourceAsStream(name);
} else throw new IllegalArgumentException("Not a valid child");
}
/**
* @param name the name of the resource requested.
* @param bcc the child object making the request.
*
* @return the requested resource as an InputStream
*/
public URL getResource(String name, BeanContextChild bcc) {
if (name == null) throw new NullPointerException("name");
if (bcc == null) throw new NullPointerException("bcc");
if (containsKey(bcc)) {
ClassLoader cl = bcc.getClass().getClassLoader();
return cl != null ? cl.getResource(name)
: ClassLoader.getSystemResource(name);
} else throw new IllegalArgumentException("Not a valid child");
}
/**
* Sets the new design time value for this {@code BeanContext}.
* @param dTime the new designTime value
*/
public synchronized void setDesignTime(boolean dTime) {
if (designTime != dTime) {
designTime = dTime;
firePropertyChange("designMode", Boolean.valueOf(!dTime), Boolean.valueOf(dTime));
}
}
/**
* Reports whether or not this object is in
* currently in design time mode.
* @return {@code true} if in design time mode,
* {@code false} if not
*/
public synchronized boolean isDesignTime() { return designTime; }
/**
* Sets the locale of this BeanContext.
* @param newLocale the new locale. This method call will have
* no effect if newLocale is {@code null}.
* @throws PropertyVetoException if the new value is rejected
*/
public synchronized void setLocale(Locale newLocale) throws PropertyVetoException {
if ((locale != null && !locale.equals(newLocale)) && newLocale != null) {
Locale old = locale;
fireVetoableChange("locale", old, newLocale); // throws
locale = newLocale;
firePropertyChange("locale", old, newLocale);
}
}
/**
* Gets the locale for this {@code BeanContext}.
*
* @return the current Locale of the {@code BeanContext}
*/
public synchronized Locale getLocale() { return locale; }
/**
* <p>
* This method is typically called from the environment in order to determine
* if the implementor "needs" a GUI.
* </p>
* <p>
* The algorithm used herein tests the BeanContextPeer, and its current children
* to determine if they are either Containers, Components, or if they implement
* Visibility and return needsGui() == true.
* </p>
* @return {@code true} if the implementor needs a GUI
*/
public synchronized boolean needsGui() {
BeanContext bc = getBeanContextPeer();
if (bc != this) {
if (bc instanceof Visibility) return ((Visibility)bc).needsGui();
if (bc instanceof Container || bc instanceof Component)
return true;
}
synchronized(children) {
for (Iterator<Object> i = children.keySet().iterator(); i.hasNext();) {
Object c = i.next();
try {
return ((Visibility)c).needsGui();
} catch (ClassCastException cce) {
// do nothing ...
}
if (c instanceof Container || c instanceof Component)
return true;
}
}
return false;
}
/**
* notify this instance that it may no longer render a GUI.
*/
public synchronized void dontUseGui() {
if (okToUseGui) {
okToUseGui = false;
// lets also tell the Children that can that they may not use their GUI's
synchronized(children) {
for (Iterator<Object> i = children.keySet().iterator(); i.hasNext();) {
Visibility v = getChildVisibility(i.next());
if (v != null) v.dontUseGui();
}
}
}
}
/**
* Notify this instance that it may now render a GUI
*/
public synchronized void okToUseGui() {
if (!okToUseGui) {
okToUseGui = true;
// lets also tell the Children that can that they may use their GUI's
synchronized(children) {
for (Iterator<Object> i = children.keySet().iterator(); i.hasNext();) {
Visibility v = getChildVisibility(i.next());
if (v != null) v.okToUseGui();
}
}
}
}
/**
* Used to determine if the {@code BeanContext}
* child is avoiding using its GUI.
* @return is this instance avoiding using its GUI?
* @see Visibility
*/
public boolean avoidingGui() {
return !okToUseGui && needsGui();
}
/**
* Is this {@code BeanContext} in the
* process of being serialized?
* @return if this {@code BeanContext} is
* currently being serialized
*/
public boolean isSerializing() { return serializing; }
/**
* Returns an iterator of all children
* of this {@code BeanContext}.
* @return an iterator for all the current BCSChild values
*/
protected Iterator<BCSChild> bcsChildren() { synchronized(children) { return children.values().iterator(); } }
/**
* called by writeObject after defaultWriteObject() but prior to
* serialization of currently serializable children.
*
* This method may be overridden by subclasses to perform custom
* serialization of their state prior to this superclass serializing
* the children.
*
* This method should not however be used by subclasses to replace their
* own implementation (if any) of writeObject().
* @param oos the {@code ObjectOutputStream} to use during serialization
* @throws IOException if serialization failed
*/
protected void bcsPreSerializationHook(ObjectOutputStream oos) throws IOException {
}
/**
* called by readObject after defaultReadObject() but prior to
* deserialization of any children.
*
* This method may be overridden by subclasses to perform custom
* deserialization of their state prior to this superclass deserializing
* the children.
*
* This method should not however be used by subclasses to replace their
* own implementation (if any) of readObject().
* @param ois the {@code ObjectInputStream} to use during deserialization
* @throws IOException if deserialization failed
* @throws ClassNotFoundException if needed classes are not found
*/
protected void bcsPreDeserializationHook(ObjectInputStream ois) throws IOException, ClassNotFoundException {
}
/**
* Called by readObject with the newly deserialized child and BCSChild.
* @param child the newly deserialized child
* @param bcsc the newly deserialized BCSChild
*/
protected void childDeserializedHook(Object child, BCSChild bcsc) {
synchronized(children) {
children.put(child, bcsc);
}
}
/**
* Used by writeObject to serialize a Collection.
* @param oos the {@code ObjectOutputStream}
* to use during serialization
* @param coll the {@code Collection} to serialize
* @throws IOException if serialization failed
*/
protected final void serialize(ObjectOutputStream oos, Collection<?> coll) throws IOException {
int count = 0;
Object[] objects = coll.toArray();
for (int i = 0; i < objects.length; i++) {
if (objects[i] instanceof Serializable)
count++;
else
objects[i] = null;
}
oos.writeInt(count); // number of subsequent objects
for (int i = 0; count > 0; i++) {
Object o = objects[i];
if (o != null) {
oos.writeObject(o);
count--;
}
}
}
/**
* used by readObject to deserialize a collection.
* @param ois the ObjectInputStream to use
* @param coll the Collection
* @throws IOException if deserialization failed
* @throws ClassNotFoundException if needed classes are not found
*/
@SuppressWarnings({"rawtypes", "unchecked"})
protected final void deserialize(ObjectInputStream ois, Collection coll) throws IOException, ClassNotFoundException {
int count = 0;
count = ois.readInt();
while (count-- > 0) {
coll.add(ois.readObject());
}
}
/**
* Used to serialize all children of
* this {@code BeanContext}.
* @param oos the {@code ObjectOutputStream}
* to use during serialization
* @throws IOException if serialization failed
*/
public final void writeChildren(ObjectOutputStream oos) throws IOException {
if (serializable <= 0) return;
boolean prev = serializing;
serializing = true;
int count = 0;
synchronized(children) {
Iterator<Map.Entry<Object, BCSChild>> i = children.entrySet().iterator();
while (i.hasNext() && count < serializable) {
Map.Entry<Object, BCSChild> entry = i.next();
if (entry.getKey() instanceof Serializable) {
try {
oos.writeObject(entry.getKey()); // child
oos.writeObject(entry.getValue()); // BCSChild
} catch (IOException ioe) {
serializing = prev;
throw ioe;
}
count++;
}
}
}
serializing = prev;
if (count != serializable) {
throw new IOException("wrote different number of children than expected");
}
}
/**
* Serialize the BeanContextSupport, if this instance has a distinct
* peer (that is this object is acting as a delegate for another) then
* the children of this instance are not serialized here due to a
* 'chicken and egg' problem that occurs on deserialization of the
* children at the same time as this instance.
*
* Therefore in situations where there is a distinct peer to this instance
* it should always call writeObject() followed by writeChildren() and
* readObject() followed by readChildren().
*
* @param oos the ObjectOutputStream
*/
private synchronized void writeObject(ObjectOutputStream oos) throws IOException, ClassNotFoundException {
serializing = true;
synchronized (BeanContext.globalHierarchyLock) {
try {
oos.defaultWriteObject(); // serialize the BeanContextSupport object
bcsPreSerializationHook(oos);
if (serializable > 0 && this.equals(getBeanContextPeer()))
writeChildren(oos);
serialize(oos, (Collection)bcmListeners);
} finally {
serializing = false;
}
}
}
/**
* When an instance of this class is used as a delegate for the
* implementation of the BeanContext protocols (and its subprotocols)
* there exists a 'chicken and egg' problem during deserialization
* @param ois the ObjectInputStream to use
* @throws IOException if deserialization failed
* @throws ClassNotFoundException if needed classes are not found
*/
public final void readChildren(ObjectInputStream ois) throws IOException, ClassNotFoundException {
int count = serializable;
while (count-- > 0) {
Object child = null;
BeanContextSupport.BCSChild bscc = null;
try {
child = ois.readObject();
bscc = (BeanContextSupport.BCSChild)ois.readObject();
} catch (IOException ioe) {
continue;
} catch (ClassNotFoundException cnfe) {
continue;
}
synchronized(child) {
BeanContextChild bcc = null;
try {
bcc = (BeanContextChild)child;
} catch (ClassCastException cce) {
// do nothing;
}
if (bcc != null) {
try {
bcc.setBeanContext(getBeanContextPeer());
bcc.addPropertyChangeListener("beanContext", childPCL);
bcc.addVetoableChangeListener("beanContext", childVCL);
} catch (PropertyVetoException pve) {
continue;
}
}
childDeserializedHook(child, bscc);
}
}
}
/**
* deserialize contents ... if this instance has a distinct peer the
* children are *not* serialized here, the peer's readObject() must call
* readChildren() after deserializing this instance.
*/
private synchronized void readObject(ObjectInputStream ois) throws IOException, ClassNotFoundException {
synchronized(BeanContext.globalHierarchyLock) {
ois.defaultReadObject();
initialize();
bcsPreDeserializationHook(ois);
if (serializable > 0 && this.equals(getBeanContextPeer()))
readChildren(ois);
deserialize(ois, bcmListeners = new ArrayList<>(1));
}
}
/**
* subclasses may envelope to monitor veto child property changes.
*/
public void vetoableChange(PropertyChangeEvent pce) throws PropertyVetoException {
String propertyName = pce.getPropertyName();
Object source = pce.getSource();
synchronized(children) {
if ("beanContext".equals(propertyName) &&
containsKey(source) &&
!getBeanContextPeer().equals(pce.getNewValue())
) {
if (!validatePendingRemove(source)) {
throw new PropertyVetoException("current BeanContext vetoes setBeanContext()", pce);
} else children.get(source).setRemovePending(true);
}
}
}
/**
* subclasses may envelope to monitor child property changes.
*/
public void propertyChange(PropertyChangeEvent pce) {
String propertyName = pce.getPropertyName();
Object source = pce.getSource();
synchronized(children) {
if ("beanContext".equals(propertyName) &&
containsKey(source) &&
children.get(source).isRemovePending()) {
BeanContext bc = getBeanContextPeer();
if (bc.equals(pce.getOldValue()) && !bc.equals(pce.getNewValue())) {
remove(source, false);
} else {
children.get(source).setRemovePending(false);
}
}
}
}
/**
* <p>
* Subclasses of this class may override, or envelope, this method to
* add validation behavior for the BeanContext to examine child objects
* immediately prior to their being added to the BeanContext.
* </p>
*
* @param targetChild the child to create the Child on behalf of
* @return true iff the child may be added to this BeanContext, otherwise false.
*/
protected boolean validatePendingAdd(Object targetChild) {
return true;
}
/**
* <p>
* Subclasses of this class may override, or envelope, this method to
* add validation behavior for the BeanContext to examine child objects
* immediately prior to their being removed from the BeanContext.
* </p>
*
* @param targetChild the child to create the Child on behalf of
* @return true iff the child may be removed from this BeanContext, otherwise false.
*/
protected boolean validatePendingRemove(Object targetChild) {
return true;
}
/**
* subclasses may override this method to simply extend add() semantics
* after the child has been added and before the event notification has
* occurred. The method is called with the child synchronized.
* @param child the child
* @param bcsc the BCSChild
*/
protected void childJustAddedHook(Object child, BCSChild bcsc) {
}
/**
* subclasses may override this method to simply extend remove() semantics
* after the child has been removed and before the event notification has
* occurred. The method is called with the child synchronized.
* @param child the child
* @param bcsc the BCSChild
*/
protected void childJustRemovedHook(Object child, BCSChild bcsc) {
}
/**
* Gets the Component (if any) associated with the specified child.
* @param child the specified child
* @return the Component (if any) associated with the specified child.
*/
protected static final Visibility getChildVisibility(Object child) {
try {
return (Visibility)child;
} catch (ClassCastException cce) {
return null;
}
}
/**
* Gets the Serializable (if any) associated with the specified Child
* @param child the specified child
* @return the Serializable (if any) associated with the specified Child
*/
protected static final Serializable getChildSerializable(Object child) {
try {
return (Serializable)child;
} catch (ClassCastException cce) {
return null;
}
}
/**
* Gets the PropertyChangeListener
* (if any) of the specified child
* @param child the specified child
* @return the PropertyChangeListener (if any) of the specified child
*/
protected static final PropertyChangeListener getChildPropertyChangeListener(Object child) {
try {
return (PropertyChangeListener)child;
} catch (ClassCastException cce) {
return null;
}
}
/**
* Gets the VetoableChangeListener
* (if any) of the specified child
* @param child the specified child
* @return the VetoableChangeListener (if any) of the specified child
*/
protected static final VetoableChangeListener getChildVetoableChangeListener(Object child) {
try {
return (VetoableChangeListener)child;
} catch (ClassCastException cce) {
return null;
}
}
/**
* Gets the BeanContextMembershipListener
* (if any) of the specified child
* @param child the specified child
* @return the BeanContextMembershipListener (if any) of the specified child
*/
protected static final BeanContextMembershipListener getChildBeanContextMembershipListener(Object child) {
try {
return (BeanContextMembershipListener)child;
} catch (ClassCastException cce) {
return null;
}
}
/**
* Gets the BeanContextChild (if any) of the specified child
* @param child the specified child
* @return the BeanContextChild (if any) of the specified child
* @throws IllegalArgumentException if child implements both BeanContextChild and BeanContextProxy
*/
protected static final BeanContextChild getChildBeanContextChild(Object child) {
try {
BeanContextChild bcc = (BeanContextChild)child;
if (child instanceof BeanContextChild && child instanceof BeanContextProxy)
throw new IllegalArgumentException("child cannot implement both BeanContextChild and BeanContextProxy");
else
return bcc;
} catch (ClassCastException cce) {
try {
return ((BeanContextProxy)child).getBeanContextProxy();
} catch (ClassCastException cce1) {
return null;
}
}
}
/**
* Fire a BeanContextshipEvent on the BeanContextMembershipListener interface
* @param bcme the event to fire
*/
protected final void fireChildrenAdded(BeanContextMembershipEvent bcme) {
Object[] copy;
synchronized(bcmListeners) { copy = bcmListeners.toArray(); }
for (int i = 0; i < copy.length; i++)
((BeanContextMembershipListener)copy[i]).childrenAdded(bcme);
}
/**
* Fire a BeanContextshipEvent on the BeanContextMembershipListener interface
* @param bcme the event to fire
*/
protected final void fireChildrenRemoved(BeanContextMembershipEvent bcme) {
Object[] copy;
synchronized(bcmListeners) { copy = bcmListeners.toArray(); }
for (int i = 0; i < copy.length; i++)
((BeanContextMembershipListener)copy[i]).childrenRemoved(bcme);
}
/**
* protected method called from constructor and readObject to initialize
* transient state of BeanContextSupport instance.
*
* This class uses this method to instantiate inner class listeners used
* to monitor PropertyChange and VetoableChange events on children.
*
* subclasses may envelope this method to add their own initialization
* behavior
*/
protected synchronized void initialize() {
children = new HashMap<>(serializable + 1);
bcmListeners = new ArrayList<>(1);
childPCL = new PropertyChangeListener() {
/*
* this adaptor is used by the BeanContextSupport class to forward
* property changes from a child to the BeanContext, avoiding
* accidential serialization of the BeanContext by a badly
* behaved Serializable child.
*/
public void propertyChange(PropertyChangeEvent pce) {
BeanContextSupport.this.propertyChange(pce);
}
};
childVCL = new VetoableChangeListener() {
/*
* this adaptor is used by the BeanContextSupport class to forward
* vetoable changes from a child to the BeanContext, avoiding
* accidential serialization of the BeanContext by a badly
* behaved Serializable child.
*/
public void vetoableChange(PropertyChangeEvent pce) throws PropertyVetoException {
BeanContextSupport.this.vetoableChange(pce);
}
};
}
/**
* Gets a copy of the this BeanContext's children.
* @return a copy of the current nested children
*/
protected final Object[] copyChildren() {
synchronized(children) { return children.keySet().toArray(); }
}
/**
* Tests to see if two class objects,
* or their names are equal.
* @param first the first object
* @param second the second object
* @return true if equal, false if not
*/
protected static final boolean classEquals(Class<?> first, Class<?> second) {
return first.equals(second) || first.getName().equals(second.getName());
}
/*
* fields
*/
/**
* all accesses to the {@code protected HashMap children} field
* shall be synchronized on that object.
*/
protected transient HashMap<Object, BCSChild> children;
private int serializable = 0; // children serializable
/**
* all accesses to the {@code protected ArrayList bcmListeners} field
* shall be synchronized on that object.
*/
protected transient ArrayList<BeanContextMembershipListener> bcmListeners;
//
/**
* The current locale of this BeanContext.
*/
protected Locale locale;
/**
* A {@code boolean} indicating if this
* instance may now render a GUI.
*/
protected boolean okToUseGui;
/**
* A {@code boolean} indicating whether or not
* this object is currently in design time mode.
*/
protected boolean designTime;
/*
* transient
*/
private transient PropertyChangeListener childPCL;
private transient VetoableChangeListener childVCL;
private transient boolean serializing;
}