// ********************************************************************** // // <copyright> // // BBN Technologies // 10 Moulton Street // Cambridge, MA 02138 // (617) 873-8000 // // Copyright (C) BBNT Solutions LLC. All rights reserved. // // </copyright> // ********************************************************************** // // $Source: /cvs/distapps/openmap/src/openmap/com/bbn/openmap/plugin/BeanContextAbstractPlugIn.java,v $ // $RCSfile: BeanContextAbstractPlugIn.java,v $ // $Revision: 1.6 $ // $Date: 2006/02/13 16:58:32 $ // $Author: dietrick $ // // ********************************************************************** package com.bbn.openmap.plugin; import java.awt.Component; import java.beans.PropertyChangeListener; import java.beans.PropertyVetoException; import java.beans.VetoableChangeListener; import java.beans.beancontext.BeanContext; import java.beans.beancontext.BeanContextChild; import java.beans.beancontext.BeanContextChildSupport; import java.beans.beancontext.BeanContextMembershipEvent; import java.beans.beancontext.BeanContextMembershipListener; import java.util.Iterator; /** * This class is an abstract implementation of the PlugIn. It does all the * things the AbstractPlugIn does, but also carries the support baggage for * PlugIns that want to play in the BeanContext. * * @see com.bbn.openmap.plugin.PlugInLayer * @see com.bbn.openmap.plugin.PlugIn * @see com.bbn.openmap.MapHandler * @see com.bbn.openmap.MapHandlerChild */ public abstract class BeanContextAbstractPlugIn extends AbstractPlugIn implements BeanContextChild, BeanContextMembershipListener { public BeanContextAbstractPlugIn() { super(); } public BeanContextAbstractPlugIn(Component comp) { super(comp); } /** * BeanContextChildSupport object provides helper functions for * BeanContextChild interface. */ protected BeanContextChildSupport beanContextChildSupport = new BeanContextChildSupport(); /** * This is the method that your object can use to find other objects within * the MapHandler (BeanContext). This method gets called when the object * gets added to the MapHandler, or when another object gets added to the * MapHandler after the object is a member. * * @param it Iterator to use to go through a list of objects. Find the ones * you need, and hook yourself up. */ public void findAndInit(Iterator it) { while (it.hasNext()) { findAndInit((Object) it.next()); } } /** * The findAndInit method has been made non-abstract, because it now calls * this method for every object that is in the iterator it receives. This * lets subclasses call a method on super classes so they can handle their * needs as well. */ public void findAndInit(Object obj) {} /** * BeanContextMembershipListener method. Called when a new object is added * to the BeanContext of this object. */ public void childrenAdded(BeanContextMembershipEvent bcme) { findAndInit(bcme.iterator()); } /** * BeanContextMembershipListener method. Called when a new object is removed * from the BeanContext of this object. For the Layer, this method doesn't * do anything. If your layer does something with the childrenAdded method, * or findAndInit, you should take steps in this method to unhook the layer * from the object used in those methods. */ public void childrenRemoved(BeanContextMembershipEvent bcme) { Iterator it = bcme.iterator(); while (it.hasNext()) { findAndUndo(it.next()); } } /** * The childrenRemoved has been changed to go through its iterator to call * this method with every object. This lets subclasses call this method on * their super class, so it can handle what it needs to with objects it may * be interested in. */ public void findAndUndo(Object obj) { // If we find that our PlugInLayer is being removed from MapHandler, we // should remove ourselves to allow proper cleanup. DFD update - the // layer how senses this and calls dispose on itself and on the plugin. // The default action is that the plugin is removed from the bean // context. } /** Method for BeanContextChild interface. */ public BeanContext getBeanContext() { return beanContextChildSupport.getBeanContext(); } /** * Method for BeanContextChild interface. Adds this object as a * BeanContextMembership listener, set the BeanContext in this objects * BeanContextSupport, and receives the initial list of objects currently * contained in the BeanContext. */ public void setBeanContext(BeanContext in_bc) throws PropertyVetoException { if (in_bc != null) { in_bc.addBeanContextMembershipListener(this); beanContextChildSupport.setBeanContext(in_bc); findAndInit(in_bc.iterator()); } } /** * Method for BeanContextChild interface. Uses the BeanContextChildSupport * to add a listener to this object's property. You don't need this function * for objects that extend java.awt.Component. */ public void addPropertyChangeListener(String propertyName, PropertyChangeListener in_pcl) { beanContextChildSupport.addPropertyChangeListener(propertyName, in_pcl); } /** * Method for BeanContextChild interface. Uses the BeanContextChildSupport * to remove a listener to this object's property. You don't need this * function for objects that extend java.awt.Component. */ public void removePropertyChangeListener(String propertyName, PropertyChangeListener in_pcl) { beanContextChildSupport.removePropertyChangeListener(propertyName, in_pcl); } /** * Method for BeanContextChild interface. Uses the BeanContextChildSupport * to add a listener to this object's property. This listener wants to have * the right to veto a property change. */ public void addVetoableChangeListener(String propertyName, VetoableChangeListener in_vcl) { beanContextChildSupport.addVetoableChangeListener(propertyName, in_vcl); } /** * Method for BeanContextChild interface. Uses the BeanContextChildSupport * to remove a listener to this object's property. The listener has the * power to veto property changes. */ public void removeVetoableChangeListener(String propertyName, VetoableChangeListener in_vcl) { beanContextChildSupport.removeVetoableChangeListener(propertyName, in_vcl); } /** * Method for BeanContextChild interface. Uses the BeanContextChildSupport * to fire a property change. You don't need this function for objects that * extend java.awt.Component. */ public void firePropertyChange(String name, Object oldValue, Object newValue) { beanContextChildSupport.firePropertyChange(name, oldValue, newValue); } /** * Report a vetoable property update to any registered listeners. If anyone * vetos the change, then fire a new event reverting everyone to the old * value and then rethrow the PropertyVetoException. * <P> * * No event is fired if old and new are equal and non-null. * <P> * * @param name The programmatic name of the property that is about to change * * @param oldValue The old value of the property * @param newValue - The new value of the property * * @throws PropertyVetoException if the recipient wishes the property change * to be rolled back. */ public void fireVetoableChange(String name, Object oldValue, Object newValue) throws PropertyVetoException { beanContextChildSupport.fireVetoableChange(name, oldValue, newValue); } }