PropertyChangeEvent.java

/*******************************************************************************
 * Copyright (c) 2011, 2015 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 v1.0 and Eclipse Distribution License v. 1.0
 * which accompanies this distribution.
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *     Oracle - initial API and implementation
 *
 ******************************************************************************/
package org.eclipse.persistence.jpa.jpql.tools.model;

import org.eclipse.persistence.jpa.jpql.tools.model.query.StateObject;

/**
 * The default implementation of {@link IPropertyChangeEvent} where the generics is the type of the
 * old and new values.
 *
 * @version 2.4
 * @since 2.4
 * @author Pascal Filion
 */
public class PropertyChangeEvent<T> implements IPropertyChangeEvent<T> {

    /**
     * The new value of the property that changed.
     */
    private T newValue;

    /**
     * The old value of the property that changed.
     */
    private T oldValue;

    /**
     * The name of the property associated with the property change.
     */
    private String propertyName;

    /**
     * The source where the modification occurred and that fired the event.
     */
    private StateObject source;

    /**
     * Creates a new <code>PropertyChangeEvent</code>.
     *
     * @param source The source where the modification occurred and that fired the event
     * @param propertyName The name of the property associated with the property change
     * @param oldValue The old value of the property that changed
     * @param newValue The new value of the property that changed
     */
    public PropertyChangeEvent(StateObject source, String propertyName, T oldValue, T newValue) {
        super();
        this.source       = source;
        this.propertyName = propertyName;
        this.oldValue     = oldValue;
        this.newValue     = newValue;
    }

    /**
     * {@inheritDoc}
     */
    public T getNewValue() {
        return newValue;
    }

    /**
     * {@inheritDoc}
     */
    public T getOldValue() {
        return oldValue;
    }

    /**
     * {@inheritDoc}
     */
    public String getPropertyName() {
        return propertyName;
    }

    /**
     * {@inheritDoc}
     */
    @SuppressWarnings("unchecked")
    public <S extends StateObject> S getSource() {
        return (S) source;
    }
}