content: /**
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You 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.apache.activemq.broker.scheduler;
  
  import java.util.Collections;
  import java.util.List;
  
  import org.apache.activemq.util.ByteSequence;
  
  /**
   * A wrapper for instances of the JobScheduler interface that ensures that methods
   * provides safe and sane return values and can deal with null values being passed
   * in etc.  Provides a measure of safety when using unknown implementations of the
   * JobSchedulerStore which might not always do the right thing.
   */
  public class JobSchedulerFacade implements JobScheduler {
  
      private final SchedulerBroker broker;
  
      JobSchedulerFacade(SchedulerBroker broker) {
          this.broker = broker;
      }
  
      @Override
      public void addListener(JobListener l) throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              js.addListener(l);
          }
      }
  
      @Override
      public List<Job> getAllJobs() throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              return js.getAllJobs();
          }
          return Collections.emptyList();
      }
  
      @Override
      public List<Job> getAllJobs(long start, long finish) throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              return js.getAllJobs(start, finish);
          }
          return Collections.emptyList();
      }
  
      @Override
      public String getName() throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              return js.getName();
          }
          return "";
      }
  
      @Override
      public List<Job> getNextScheduleJobs() throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              return js.getNextScheduleJobs();
          }
          return Collections.emptyList();
      }
  
      @Override
      public long getNextScheduleTime() throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              return js.getNextScheduleTime();
          }
          return 0;
      }
  
      @Override
      public void remove(long time) throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              js.remove(time);
          }
      }
  
      @Override
      public void remove(String jobId) throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              js.remove(jobId);
          }
      }
  
      @Override
      public void removeAllJobs() throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              js.removeAllJobs();
          }
      }
  
      @Override
      public void removeAllJobs(long start, long finish) throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              js.removeAllJobs(start, finish);
          }
      }
  
      @Override
      public void removeListener(JobListener l) throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              js.removeListener(l);
          }
      }
  
      @Override
      public void schedule(String jobId, ByteSequence payload, long delay) throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              js.schedule(jobId, payload, delay);
          }
      }
  
      @Override
      public void schedule(String jobId, ByteSequence payload, String cronEntry, long start, long period, int repeat) throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              js.schedule(jobId, payload, cronEntry, start, period, repeat);
          }
      }
  
      @Override
      public void schedule(String jobId, ByteSequence payload, String cronEntry) throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              js.schedule(jobId, payload, cronEntry);
          }
      }
  
      @Override
      public void startDispatching() throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              js.startDispatching();
          }
      }
  
      @Override
      public void stopDispatching() throws Exception {
          JobScheduler js = this.broker.getInternalScheduler();
          if (js != null) {
              js.stopDispatching();
          }
      }
  }
  