/*
 * @(#)BeanContextChild.java	1.17 01/12/03
 *
 * Copyright 2002 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package java.beans.beancontext;

import java.beans.PropertyChangeListener;
import java.beans.VetoableChangeListener;
import java.beans.PropertyVetoException;

import java.beans.beancontext.BeanContext;

/**
 * <p>
 * JavaBeans wishing to be nested within, and obtain a reference to their
 * execution environment, or context, as defined by the BeanContext
 * sub-interface shall implement this interface.
 * </p>
 * <p>
 * Conformant BeanContexts shall as a side effect of adding a BeanContextChild
 * object shall pass a reference to itself via the setBeanContext() method of
 * this interface.
 * </p>
 * <p>
 * Note that a BeanContextChild may refuse a change in state by throwing
 * PropertyVetoedException in response.
 * </p>
 * <p>
 * In order for persistence mechanisms to function properly on BeanContextChild
 * instances across a broad variety of scenarios, implementing classes of this
 * interface are required to define as transient, any or all fields, or
 * instance variables, that may contain, or represent, references to the
 * nesting BeanContext instance or other resources obtained
 * from the BeanContext via any unspecified mechanisms.
 * </p>
 *
 * @author	Laurence P. G. Cable
 * @version	1.17, 12/03/01
 * @since	1.2
 * 
 * @seealso	java.beans.beancontext.BeanContext
 * @seealso	java.beans.PropertyChangeEvent
 * @seealso	java.beans.PropertyChangeListener
 * @seealso	java.beans.PropertyVetoEvent
 * @seealso	java.beans.PropertyVetoListener
 * @seealso	java.beans.PropertyVetoException
 */

public interface BeanContextChild {

    /**
     * <p>
     * Objects that implement this interface, 
     * shall fire a java.beans.PropertyChangeEvent, with parameters:
     *
     * propertyName "beanContext", oldValue (the previous nesting 
     * <code>BeanContext</code> instance, or <code>null</code>), 
     * newValue (the current nesting 
     * <code>BeanContext</code> instance, or <code>null</code>).
     * <p>
     * A change in the value of the nesting BeanContext property of this
     * BeanContextChild may be vetoed by throwing the appropriate exception.
     * </p>
     * @param bc The <code>BeanContext</code> with which 
     * to associate this <code>BeanContextChild</code>.
     * @throws <code>PropertyVetoException</code> if the 
     * addition of the specified <code>BeanContext</code> is refused.
     */
    void setBeanContext(BeanContext bc) throws PropertyVetoException;

    /**
     * Gets the <code>BeanContext</code> associated 
     * with this <code>BeanContextChild</code>.
     * @return the <code>BeanContext</code> associated 
     * with this <code>BeanContextChild</code>.
     */
    BeanContext getBeanContext();

    /**
     * Adds a <code>PropertyChangeListener</code> 
     * to this <code>BeanContextChild</code> 
     * in order to receive a <code>PropertyChangeEvent</code> 
     * whenever the specified property has changed.
     * @param name the name of the property to listen on
     * @param pcl the <code>PropertyChangeListener</code> to add
     */
    void addPropertyChangeListener(String name, PropertyChangeListener pcl);

    /**
     * Removes a <code>PropertyChangeListener</code> from this 
     * <code>BeanContextChild</code>  so that it no longer 
     * receives <code>PropertyChangeEvents</code> when the 
     * specified property is changed.
     * 
     * @param name the name of the property that was listened on
     * @param pcl the <code>PropertyChangeListener</code> to remove
     */
    void removePropertyChangeListener(String name, PropertyChangeListener pcl);

    /**
     * Adds a <code>VetoableChangeListener</code> to 
     * this <code>BeanContextChild</code>  
     * to receive events whenever the specified property changes.
     * @param name the name of the property to listen on
     * @param vcl the <code>VetoableChangeListener</code> to add
     */
    void addVetoableChangeListener(String name, VetoableChangeListener vcl);

    /**
     * Removes a <code>VetoableChangeListener</code> from this 
     * <code>BeanContextChild</code> so that it no longer receives 
     * events when the specified property changes.
     * @param name the name of the property that was listened on.
     * @param vcl the <code>VetoableChangeListener</code> to remove.
     */
    void removeVetoableChangeListener(String name, VetoableChangeListener vcl);

}
