BufferedCommandQueue.java

/**
 * Copyright 2008 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 org.waveprotocol.wave.client.scheduler;

import com.google.gwt.user.client.Command;

import java.util.LinkedList;
import java.util.List;

/**
 * Basic command queue that queues up commands and runs them all in
 * {@link #execute()}.
 *
 */
public class BufferedCommandQueue implements Command, CommandQueue {
  /** Queued commands, with a FIFO-suitable implementation. */
  private final List<Command> commands = new LinkedList<Command>();

  /** {@inheritDoc} */
  public void addCommand(Command c) {
    commands.add(c);
  }

  /**
   * Runs all the commands in the queue until it's empty.
   */
  public void execute() {
    while (!commands.isEmpty()) {
      commands.remove(0).execute();
    }
  }

  /**
   * @return whether there are any queued commands.
   */
  public boolean isEmpty() {
    return commands.isEmpty();
  }
}