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Utility classes for Jetty
//========================================================================
//Copyright 2005 Mort Bay Consulting Pty. Ltd.
//------------------------------------------------------------------------
//Licensed under the Apache License, Version 2.0 (the "License");
//you may not use this file except in compliance with the License.
//You may obtain a copy of the License at
//http://www.apache.org/licenses/LICENSE-2.0
//Unless required by applicable law or agreed to in writing, software
//distributed under the License is distributed on an "AS IS" BASIS,
//WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//See the License for the specific language governing permissions and
//limitations under the License.
//========================================================================
package org.mortbay.component;
import java.util.EventListener;
import org.mortbay.log.Log;
import org.mortbay.util.LazyList;
/* ------------------------------------------------------------ */
/** Container.
* This class allows a containment events to be generated from update methods.
*
* The style of usage is:
* public void setFoo(Foo foo)
* {
* getContainer().update(this,this.foo,foo,"foo");
* this.foo=foo;
* }
*
* public void setBars(Bar[] bars)
* {
* getContainer().update(this,this.bars,bars,"bar");
* this.bars=bars;
* }
*
*
* @author gregw
*
*/
public class Container
{
private Object _listeners;
public synchronized void addEventListener(Container.Listener listener)
{
_listeners=LazyList.add(_listeners,listener);
}
public synchronized void removeEventListener(Container.Listener listener)
{
_listeners=LazyList.remove(_listeners,listener);
}
/* ------------------------------------------------------------ */
/** Update single parent to child relationship.
* @param parent The parent of the child.
* @param oldChild The previous value of the child. If this is non null and differs from child, then a remove event is generated.
* @param child The current child. If this is non null and differs from oldChild, then an add event is generated.
* @param relationship The name of the relationship
*/
public synchronized void update(Object parent, Object oldChild, final Object child, String relationship)
{
if (oldChild!=null && !oldChild.equals(child))
remove(parent,oldChild,relationship);
if (child!=null && !child.equals(oldChild))
add(parent,child,relationship);
}
/* ------------------------------------------------------------ */
/** Update single parent to child relationship.
* @param parent The parent of the child.
* @param oldChild The previous value of the child. If this is non null and differs from child, then a remove event is generated.
* @param child The current child. If this is non null and differs from oldChild, then an add event is generated.
* @param relationship The name of the relationship
* @param addRemoveBean If true add/remove is called for the new/old children as well as the relationships
*/
public synchronized void update(Object parent, Object oldChild, final Object child, String relationship,boolean addRemove)
{
if (oldChild!=null && !oldChild.equals(child))
{
remove(parent,oldChild,relationship);
if (addRemove)
removeBean(oldChild);
}
if (child!=null && !child.equals(oldChild))
{
if (addRemove)
addBean(child);
add(parent,child,relationship);
}
}
/* ------------------------------------------------------------ */
/** Update multiple parent to child relationship.
* @param parent The parent of the child.
* @param oldChildren The previous array of children. A remove event is generated for any child in this array but not in the children array.
* This array is modified and children that remain in the new children array are nulled out of the old children array.
* @param children The current array of children. An add event is generated for any child in this array but not in the oldChildren array.
* @param relationship The name of the relationship
*/
public synchronized void update(Object parent, Object[] oldChildren, final Object[] children, String relationship)
{
update(parent,oldChildren,children,relationship,false);
}
/* ------------------------------------------------------------ */
/** Update multiple parent to child relationship.
* @param parent The parent of the child.
* @param oldChildren The previous array of children. A remove event is generated for any child in this array but not in the children array.
* This array is modified and children that remain in the new children array are nulled out of the old children array.
* @param children The current array of children. An add event is generated for any child in this array but not in the oldChildren array.
* @param relationship The name of the relationship
* @param addRemoveBean If true add/remove is called for the new/old children as well as the relationships
*/
public synchronized void update(Object parent, Object[] oldChildren, final Object[] children, String relationship, boolean addRemove)
{
Object[] newChildren = null;
if (children!=null)
{
newChildren = new Object[children.length];
for (int i=children.length;i-->0;)
{
boolean new_child=true;
if (oldChildren!=null)
{
for (int j=oldChildren.length;j-->0;)
{
if (children[i]!=null && children[i].equals(oldChildren[j]))
{
oldChildren[j]=null;
new_child=false;
}
}
}
if (new_child)
newChildren[i]=children[i];
}
}
if (oldChildren!=null)
{
for (int i=oldChildren.length;i-->0;)
{
if (oldChildren[i]!=null)
{
remove(parent,oldChildren[i],relationship);
if (addRemove)
removeBean(oldChildren[i]);
}
}
}
if (newChildren!=null)
{
for (int i=0;i"+_child;
}
public int hashCode()
{
return _parent.hashCode()+_child.hashCode()+_relationship.hashCode();
}
public boolean equals(Object o)
{
if (o==null || !(o instanceof Relationship))
return false;
Relationship r = (Relationship)o;
return r._parent==_parent && r._child==_child && r._relationship.equals(_relationship);
}
}
/* ------------------------------------------------------------ */
/** Listener.
* A listener for Container events.
*/
public interface Listener extends EventListener
{
public void addBean(Object bean);
public void removeBean(Object bean);
public void add(Container.Relationship relationship);
public void remove(Container.Relationship relationship);
}
}