| /* |
| * Copyright (c) 2011, 2012, 2015 Eike Stepper (Berlin, Germany) and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * Eike Stepper - initial API and implementation |
| */ |
| package org.eclipse.net4j.util.event; |
| |
| import org.eclipse.net4j.util.ObjectUtil; |
| |
| /** |
| * A {@link INotifier notifier} with an {@link #getID() ID} and a single {@link #getValue() value}. |
| * <p> |
| * A value notifier can fire the following events: |
| * <ul> |
| * <li> {@link ValueEvent} after value changes. |
| * </ul> |
| * |
| * @author Eike Stepper |
| * @since 3.1 |
| * @apiviz.has {@link java.lang.Object} oneway - - value |
| * @apiviz.uses {@link ValueEvent} - - fires |
| */ |
| public class ValueNotifier<VALUE> extends Notifier |
| { |
| private String id; |
| |
| private VALUE value; |
| |
| public ValueNotifier() |
| { |
| this(null, null); |
| } |
| |
| public ValueNotifier(VALUE value) |
| { |
| this(null, value); |
| } |
| |
| public ValueNotifier(String id) |
| { |
| this(id, null); |
| } |
| |
| public ValueNotifier(String id, VALUE value) |
| { |
| this.id = id; |
| this.value = value; |
| } |
| |
| public String getID() |
| { |
| return id; |
| } |
| |
| public VALUE getValue() |
| { |
| return value; |
| } |
| |
| public synchronized void setValue(VALUE value) |
| { |
| VALUE oldValue = this.value; |
| if (!ObjectUtil.equals(value, oldValue)) |
| { |
| this.value = value; |
| fireEvent(new ValueEvent<VALUE>(this, oldValue, value)); |
| } |
| } |
| } |