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Diffstat (limited to 'libjava/java/beans/beancontext/BeanContextChildSupport.java')
| -rw-r--r-- | libjava/java/beans/beancontext/BeanContextChildSupport.java | 356 |
1 files changed, 0 insertions, 356 deletions
diff --git a/libjava/java/beans/beancontext/BeanContextChildSupport.java b/libjava/java/beans/beancontext/BeanContextChildSupport.java deleted file mode 100644 index 08d2a718ea4..00000000000 --- a/libjava/java/beans/beancontext/BeanContextChildSupport.java +++ /dev/null @@ -1,356 +0,0 @@ -/* java.beans.beancontext.BeanContextChildSupport - Copyright (C) 1999 Free Software Foundation, Inc. - -This file is part of GNU Classpath. - -GNU Classpath is free software; you can redistribute it and/or modify -it under the terms of the GNU General Public License as published by -the Free Software Foundation; either version 2, or (at your option) -any later version. - -GNU Classpath 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 for more details. - -You should have received a copy of the GNU General Public License -along with GNU Classpath; see the file COPYING. If not, write to the -Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA -02111-1307 USA. - -As a special exception, if you link this library with other files to -produce an executable, this library does not by itself cause the -resulting executable to be covered by the GNU General Public License. -This exception does not however invalidate any other reasons why the -executable file might be covered by the GNU General Public License. */ - - -package java.beans.beancontext; - -import java.beans.PropertyChangeListener; -import java.beans.VetoableChangeListener; -import java.beans.PropertyVetoException; -import java.beans.PropertyChangeEvent; -import java.beans.PropertyChangeSupport; -import java.beans.VetoableChangeSupport; -import java.io.Serializable; - -/** - * Support for creating a <code>BeanContextChild</code>. - * This class contains the most common implementations of the methods in - * the <code>BeanContextChild</code> - * - * @specnote This class is not very well specified. I had to "fill in the - * blanks" in most places with what I thought was reasonable - * behavior. If there are problems, let me know. - * - * @author John Keiser - * @since JDK1.2 - * @see java.beans.beancontext.BeanContextChild - */ - -public class BeanContextChildSupport implements BeanContextChild, BeanContextServicesListener, Serializable { - /** - * The peer on which to perform <code>set</code> actions. - * This is here so that this class can be used as a peer. - * <P> - * - * When extending this class, this variable will be set to - * <code>this</code>. - */ - public BeanContextChild beanContextChildPeer; - - /** - * The parent <code>BeanContext</code>. - */ - protected transient BeanContext beanContext; - - /** - * If <code>setBeanContext()</code> was vetoed once before, this - * is set to <code>true</code> so that the next time, vetoes will - * be ignored. - */ - protected transient boolean rejectedSetBCOnce; - - /** - * Listeners are registered here and events are fired through here. - */ - protected PropertyChangeSupport pcSupport; - - /** - * Listeners are registered here and events are fired through here. - */ - protected VetoableChangeSupport vcSupport; - - - /** - * Create a new <code>BeanContextChildSupport</code> with itself as the peer. - * This is meant to be used when you subclass - * <code>BeanContextChildSupport</code> to create your child. - */ - public BeanContextChildSupport() { - this(null); - }; - - /** - * Create a new <code>BeanContextChildSupport</code> with the specified peer. - * @param peer the peer to use, or <code>null</code> to specify - * <code>this</code>. - */ - public BeanContextChildSupport(BeanContextChild peer) { - if(peer == null) { - peer = this; - } - - beanContextChildPeer = peer; - pcSupport = new PropertyChangeSupport(peer); - vcSupport = new VetoableChangeSupport(peer); - } - - /** - * Set the parent <code>BeanContext</code>. - * <P> - * - * When this Object is being added to a new BeanContext or moved - * from an old one, a non-null value will be passed in. - * <P> - * - * When this Object is being removed from the current - * <code>BeanContext</code>, <code>setBeanContext()</code> will - * receive the parameter <code>null</code>. - * <P> - * - * Order of events: - * <OL> - * <LI> - * If the new <code>BeanContext</code> is the same as the old - * one, nothing happens. - * </LI> - * <LI> - * If the change has not been rejected or vetoed before, call - * <code>validatePendingSetBeanContext()</code>. If this call - * returns <code>false</code>, the change is rejected and a - * <code>PropertyVetoException</code> is thrown. - * </LI> - * <LI> - * If the change has not been rejected or vetoed before, - * <code>VetoableChangeEvent</code>s are fired with the name - * <code>"beanContext"</code>, using the - * <code>fireVetoableChange()</code> method. If a veto - * occurs, reversion events are fired using the same method, - * the change is rejected, and the veto is rethrown. - * </LI> - * <LI> - * <code>releaseBeanContextResources()</code> is called. - * </LI> - * <LI> - * The change is made. - * </LI> - * <LI> - * <code>PropertyChangeEvent</code>s are fired using the - * <code>firePropertyChange()</code> method. - * </LI> - * <LI> - * <code>initializeBeanContextResources()</code> is called. - * </LI> - * </OL> - * <P> - * - * @param newBeanContext the new parent for the - * <code>BeanContextChild</code>, or <code>null</code> to - * signify removal from a tree. - * @exception PropertyVetoException if the - * <code>BeanContextChild</code> implementor does not - * wish to have its parent changed. - */ - public void setBeanContext(BeanContext newBeanContext) - throws PropertyVetoException { - synchronized(beanContextChildPeer) { - if(newBeanContext == beanContext) - return; - - if(!rejectedSetBCOnce) { - if(!validatePendingSetBeanContext(newBeanContext)) { - rejectedSetBCOnce = true; - throw new PropertyVetoException("validatePendingSetBeanContext() rejected change", - new PropertyChangeEvent(beanContextChildPeer, "beanContext", beanContext, newBeanContext)); - } - try { - fireVetoableChange("beanContext", beanContext, newBeanContext); - } catch(PropertyVetoException e) { - rejectedSetBCOnce = true; - throw e; - } - } - - releaseBeanContextResources(); - - beanContext = newBeanContext; - rejectedSetBCOnce = false; - - firePropertyChange("beanContext", beanContext, newBeanContext); - - initializeBeanContextResources(); - } - } - - /** - * Get the parent <code>BeanContext</code>. - * @return the parent <code>BeanContext</code>. - */ - public BeanContext getBeanContext() { - return beanContext; - } - - /** - * Get the peer (or <code>this</code> if there is no peer). - * @return the peer, or <code>this</code> if there is no peer. - */ - public BeanContextChild getBeanContextChildPeer() { - return beanContextChildPeer; - } - - /** - * Determine whether there is a peer. - * This is true iff <code>getBeanContextChildPeer() == this</code>. - * @return whether there is a peer. - */ - public boolean isDelegated() { - return beanContextChildPeer == this; - } - - /** - * Add a listener that will be notified when a specific property changes. - * @param propertyName the name of the property to listen on. - * @param listener the listener to listen on the property. - */ - public void addPropertyChangeListener(String propertyName, PropertyChangeListener listener) { - pcSupport.addPropertyChangeListener(propertyName, listener); - } - - /** - * Remove a listener to a certain property. - * - * @param propertyName the name of the property being listened on. - * @param listener the listener listening on the property. - */ - public void removePropertyChangeListener(String propertyName, PropertyChangeListener listener) { - pcSupport.removePropertyChangeListener(propertyName, listener); - } - - /** - * Add a listener that will be notified when a specific property - * change is requested (a PropertyVetoException may be thrown) as - * well as after the change is successfully made. - * - * @param propertyName the name of the property to listen on. - * @param listener the listener to listen on the property. - */ - public void addVetoableChangeListener(String propertyName, VetoableChangeListener listener) { - vcSupport.addVetoableChangeListener(propertyName, listener); - } - - /** - * Remove a listener to a certain property. - * - * @param propertyName the name of the property being listened on - * @param listener the listener listening on the property. - */ - public void removeVetoableChangeListener(String propertyName, VetoableChangeListener listener) { - vcSupport.removeVetoableChangeListener(propertyName, listener); - } - - /** - * Fire a property change. - * - * @param propertyName the name of the property that changed - * @param oldVal the old value of the property - * @param newVal the new value of the property - */ - public void firePropertyChange(String propertyName, Object oldVal, Object newVal) { - pcSupport.firePropertyChange(propertyName, oldVal, newVal); - } - - /** - * Fire a vetoable property change. - * - * @param propertyName the name of the property that changed - * @param oldVal the old value of the property - * @param newVal the new value of the property - * @exception PropertyVetoException if the change is vetoed. - */ - public void fireVetoableChange(String propertyName, Object oldVal, Object newVal) - throws PropertyVetoException { - vcSupport.fireVetoableChange(propertyName, oldVal, newVal); - } - - /** - * Called by <code>BeanContextServices.revokeService()</code> to indicate that a service has been revoked. - * If you have a reference to such a service, it should be - * discarded and may no longer function properly. - * <code>getService()</code> will no longer work on the specified - * service class after this event has been fired. - * <P> - * - * <EM>This method is meant to be overriden.</EM> - * <code>BeanContextChildSupport</code>'s implementation does - * nothing. - * - * @param event the service revoked event. - * @see java.beans.beancontext.BeanContextServices#revokeService(java.lang.Class,java.beans.beancontext.BeanContextServiceProvider,boolean) - */ - public void serviceRevoked(BeanContextServiceRevokedEvent event) { - } - - /** - * Called by <code>BeanContextServices</code> whenever a service is made available. - * <P> - * - * <EM>This method is meant to be overriden.</EM> - * <code>BeanContextChildSupport</code>'s implementation does - * nothing. - * - * @param event the service revoked event, with useful information - * about the new service. - */ - public void serviceAvailable(BeanContextServiceAvailableEvent event) { - } - - /** - * Called by <code>setBeanContext()</code> to determine whether the set should be rejected. - * <P> - * - * <EM>This method is meant to be overriden.</EM> - * <code>BeanContextChildSupport</code>'s implementation simply - * returns <code>true</code>. - * - * @param newBeanContext the new parent. - * @return whether to allow the parent to be changed to the new - * value. - */ - public boolean validatePendingSetBeanContext(BeanContext newBeanContext) { - return true; - } - - /** - * Called by <code>setBeanContext()</code> to release resources of a what will soon no longer be the parent. - * <P> - * - * <EM>This method is meant to be overriden.</EM> - * <code>BeanContextChildSupport</code>'s implementation does - * nothing. - */ - protected void releaseBeanContextResources() { - } - - /** - * Called by <code>setBeanContext()</code> to grab resources when the parent has been set. - * <P> - * - * <EM>This method is meant to be overriden.</EM> - * <code>BeanContextChildSupport</code>'s implementation does - * nothing. - */ - protected void initializeBeanContextResources() { - } -} |