174 lines
6.7 KiB
Java
174 lines
6.7 KiB
Java
/* java.beans.beancontext.BeanContextChild
|
|
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.
|
|
|
|
Linking this library statically or dynamically with other modules is
|
|
making a combined work based on this library. Thus, the terms and
|
|
conditions of the GNU General Public License cover the whole
|
|
combination.
|
|
|
|
As a special exception, the copyright holders of this library give you
|
|
permission to link this library with independent modules to produce an
|
|
executable, regardless of the license terms of these independent
|
|
modules, and to copy and distribute the resulting executable under
|
|
terms of your choice, provided that you also meet, for each linked
|
|
independent module, the terms and conditions of the license of that
|
|
module. An independent module is a module which is not derived from
|
|
or based on this library. If you modify this library, you may extend
|
|
this exception to your version of the library, but you are not
|
|
obligated to do so. If you do not wish to do so, delete this
|
|
exception statement from your version. */
|
|
|
|
|
|
package java.beans.beancontext;
|
|
|
|
import java.beans.PropertyChangeListener;
|
|
import java.beans.VetoableChangeListener;
|
|
import java.beans.PropertyVetoException;
|
|
|
|
/**
|
|
* Beans implement this to get information about the execution environment and its services and to be placed in the hierarchy.
|
|
* <P>
|
|
*
|
|
* The difference between a <code>BeanContext</code> and a
|
|
* <code>BeanContextChild</code>, mainly, is that a
|
|
* <code>BeanContext</code> may be a parent.
|
|
* <P>
|
|
*
|
|
* <code>BeanContextChild</code> instances will be serialized at some
|
|
* point in their life, but you need to make sure your bean context does
|
|
* not contain a serializable reference (directly or indirectly) to the
|
|
* parent <code>BeanContext</code>, to any of the other
|
|
* <code>BeanContext</code>s in the tree, or to any resources obtained
|
|
* via the <code>BeanContextServices</code> interface. One way to do this
|
|
* is to mark any fields that contain such references as
|
|
* <code>transient</code>. Another way is to use a custom serializer.
|
|
* <P>
|
|
*
|
|
* If you do not do this, when the <code>BeanContext</code> is serialized,
|
|
* all the other <code>BeanContext</code>s and other unnecessary things
|
|
* will be serialized along with it.
|
|
* <P>
|
|
*
|
|
* Before dying, a <code>BeanContextChild</code> should call
|
|
* <code>getBeanContext().remove(this)</code> to detach from the
|
|
* hierarchy and exit cleanly.
|
|
*
|
|
* @author John Keiser
|
|
* @since JDK1.2
|
|
* @see java.beans.beancontext.BeanContext
|
|
*/
|
|
|
|
public interface BeanContextChild {
|
|
/**
|
|
* Set the parent <code>BeanContext</code>.
|
|
* <P>
|
|
*
|
|
* This method is called from <code>BeanContext.add()</code> and
|
|
* should not be called directly.
|
|
* <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>
|
|
*
|
|
* When being removed from the current <code>BeanContext</code>,
|
|
* it is the <code>BeanContextChild</code>'s responsibility to
|
|
* release all services it has obtained.
|
|
* <P>
|
|
*
|
|
* This change should generate <code>PropertyChangeEvent</code>
|
|
* and <code>VetoableChangeEvent</code>s with the property name
|
|
* "beanContext". If the change is vetoed, it must re-throw the
|
|
* exception and not change anything. In this way, the parent
|
|
* <code>BeanContextChild</code>, who has registered himself with
|
|
* you, will have a chance to remove this child from its
|
|
* collection.
|
|
* <P>
|
|
*
|
|
* If the Bean does not wish to change the parent or be removed
|
|
* from one, it may throw the <code>PropertyVetoException</code>.
|
|
* If you veto a <code>setBeanContext(null)</code> call, then you
|
|
* should try your hardest to remedy whatever problem is keeping
|
|
* you from being removed from the <code>BeanContext</code> so
|
|
* that you can <em>not</em> veto it the next time.
|
|
* Otherwise, nasty pathological recursion stuff could occur in
|
|
* certain situations.
|
|
* <P>
|
|
*
|
|
* If you do veto the change, you must first back out any changes
|
|
* you made prior to the veto. Best not to make any such changes
|
|
* prior to the veto in the first place.
|
|
* <P>
|
|
*
|
|
* This method is called from <code>BeanContext.add()</code> and
|
|
* should not be called directly.
|
|
*
|
|
* @param parent 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 parent)
|
|
throws PropertyVetoException;
|
|
|
|
/**
|
|
* Get the parent <code>BeanContext</code>.
|
|
* @return the parent <code>BeanContext</code>.
|
|
*/
|
|
public BeanContext getBeanContext();
|
|
|
|
/**
|
|
* Add a listener that will be notified when a specific property changes.
|
|
* @param prop the name of the property to listen on
|
|
* @param listener the listener to listen on the property.
|
|
*/
|
|
public void addPropertyChangeListener(String prop, PropertyChangeListener listener);
|
|
|
|
/**
|
|
* Remove a listener to a certain property.
|
|
* @param prop the name of the property being listened on
|
|
* @param listener the listener listening on the property.
|
|
*/
|
|
public void removePropertyChangeListener(String prop, PropertyChangeListener 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 prop the name of the property to listen on
|
|
* @param listener the listener to listen on the property.
|
|
*/
|
|
public void addVetoableChangeListener(String prop, VetoableChangeListener listener);
|
|
|
|
/**
|
|
* Remove a listener to a certain property.
|
|
* @param prop the name of the property being listened on
|
|
* @param listener the listener listening on the property.
|
|
*/
|
|
public void removeVetoableChangeListener(String prop, VetoableChangeListener listener);
|
|
}
|