/*
* Copyright 2006 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package com.google.gwt.user.client;
import com.google.gwt.core.client.Scheduler;
/**
* Encapsulates an action for later execution, often from a different context.
*
* <p>
* The Command interface provides a layer of separation between the code
* specifying some behavior and the code invoking that behavior. This separation
* aids in creating reusable code. For example, a
* {@link com.google.gwt.user.client.ui.MenuItem} can have a Command associated
* with it that it executes when the menu item is chosen by the user.
* Importantly, the code that constructed the Command to be executed when the
* menu item is invoked knows nothing about the internals of the MenuItem class
* and vice-versa.
* </p>
*
* <p>
* The Command interface is often implemented with an anonymous inner class. For
* example,
*
* <pre>
* Command sayHello = new Command() {
* public void execute() {
* Window.alert("Hello");
* }
* };
* sayHello.execute();
* </pre>
*
* </p>
* This type extends ScheduledCommand to help migrate from DeferredCommand API.
*/
public interface Command extends Scheduler.ScheduledCommand {
/**
* Causes the Command to perform its encapsulated behavior.
*/
void execute();
}