beancontextsupport.java

JAVA基本类源代码,大家可以学习学习!

     * 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 <tt>setBeanContext</tt> or
     * by <tt>remove()</tt> 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 <tt>BeanContext</tt>.
     */
    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  = (BCSChild)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 = (BCSChild)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 <tt>Collection</tt> are children of
     * this <tt>BeanContext</tt>.
     * @param c the specified <tt>Collection</tt> 
     * 
     * @return <tt>true</tt> if all objects 
     * in the collection are children of 
     * this <tt>BeanContext</tt>, false if not.
     */
    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
     */
    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
     */
    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
     */
    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
     */
    public void clear() {
	throw new UnsupportedOperationException();
    }

    /**
     * Adds a BeanContextMembershipListener
     *
     * @param  bcml the BeanContextMembershipListener to add
     * @throws NullPointerException
     */

    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
     */

    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
     */

    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 <tt>BeanContext</tt>.
     * @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 <tt>true</tt> if in design time mode, 
     * <tt>false</tt> 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</CODE>.
     * @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 <tt>BeanContext</tt>.
     *
     * @return the current Locale of the <tt>BeanContext</tt>
     */
    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 <tt>true</tt> 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 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 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 i = children.keySet().iterator(); i.hasNext();) {
		    Visibility v = getChildVisibility(i.next());

		    if (v != null) v.okToUseGui();
	        }
	    }
	}
    }

    /**
     * Used to determine if the <tt>BeanContext</tt> 
     * child is avoiding using its GUI.
     * @return is this instance avoiding using its GUI?
     * @see Visibility
     */
    public boolean avoidingGui() {
	return !okToUseGui && needsGui();
    }

    /**
     * Is this <tt>BeanContext</tt> in the 
     * process of being serialized?
     * @return if this <tt>BeanContext</tt> is 
     * currently being serialized
     */
    public boolean isSerializing() { return serializing; }

    /**
     * Returns an iterator of all children 
     * of this <tt>BeanContext</tt>.
     * @return an iterator for all the current BCSChild values 
     */
    protected Iterator 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().
     */

    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().
     */

    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 <tt>ObjectOutputStream</tt> 
     * to use during serialization
     * @param coll the <tt>Collection</tt> 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
     */
    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 <tt>BeanContext</tt>.
     * @param oos the <tt>ObjectOutputStream</tt> 
     * to use during serialization
     * @throws IOException if serialization failed
     */
    public final void writeChildren(ObjectOutputStream oos) throws IOException {
	if (serializable <= 0) return;