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EclipseLink build based upon Git transaction ecdf3c32c4
/*
* Copyright (c) 1998, 2018 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0 which is available at
* http://www.eclipse.org/legal/epl-2.0,
* or the Eclipse Distribution License v. 1.0 which is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
*/
// Contributors:
// Oracle - initial API and implementation from Oracle TopLink
package org.eclipse.persistence.internal.descriptors.changetracking;
import java.beans.*;
import java.io.Serializable;
/**
*
* Purpose: Define a listener for object change tracking.
*
* Description: Listener is notified on a PropertyChangeEvent from the object it belongs to.
*
* Responsibilities: Set the flag to true when there is any change in the object.
*
*
*/
public class ObjectChangeListener implements PropertyChangeListener, Serializable {
// when EclipseLink merges events should be ignored that are not issued by EclipseLink
// ie when EclipseLink call setters.
protected boolean ignoreEvents = false;
// this is used to treat ignoreEvents as a nestable call. In numerous
// places EclipseLink will disable events, do some work and re-enable. Within
// that work there may be other disable/enable pairs. This flag will allow EclipseLink
// to nest the disable/enable pairs and ensure the event is only enabled when the original
// caller finally enables the events.
protected int ignoreDepth = 0;
protected boolean hasChanges;
/**
* INTERNAL:
* Create a ObjectChangeListener
*/
public ObjectChangeListener() {
hasChanges = false;
}
/**
* INTERNAL:
* This method will set this listener to ignore events not issues by EclipseLink
*/
public void ignoreEvents(){
++ignoreDepth;
this.ignoreEvents = true;
}
/**
* INTERNAL:
* This method will set this listener to ignore events not issues by EclipseLink
*/
public void processEvents(){
--ignoreDepth;
if (ignoreDepth == 0) {
this.ignoreEvents = false;
}
}
/**
* PUBLIC:
* This method turns marks the object as changed.
*/
public void propertyChange(PropertyChangeEvent evt) {
if (this.ignoreEvents){
return;
}
internalPropertyChange(evt);
}
/**
* INTERNAL:
* This method turns marks the object as changed. This method is only
* called by EclipseLink
*/
public void internalPropertyChange(PropertyChangeEvent evt) {
if (evt.getNewValue() == evt.getOldValue()) {
return;
}
hasChanges = true;
}
/**
* INTERNAL:
* This method should return true if the object has been changed and false otherwise. Changed
* Objects will be compared for changes in the UnitOfWork commit process. Unchanged objects
* will not be compared.
*/
public boolean hasChanges() {
return hasChanges;
}
/**
* INTERNAL:
* Clear a change flag used in this method. This will be called in TopLink's UnitOfWork
* commit process when a change set has been calculated for an object.
*/
public void clearChanges(boolean forRefresh) {
hasChanges = false;
}
}