content: /*
   * Copyright 2010-2025 Hyland Software, Inc. and its affiliates.
   *
   * 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.activiti.engine.impl.cmd;
  
  import java.util.Calendar;
  import java.util.GregorianCalendar;
  import java.util.List;
  import org.activiti.engine.impl.Page;
  import org.activiti.engine.impl.asyncexecutor.AcquiredTimerJobEntities;
  import org.activiti.engine.impl.asyncexecutor.AsyncExecutor;
  import org.activiti.engine.impl.interceptor.Command;
  import org.activiti.engine.impl.interceptor.CommandContext;
  import org.activiti.engine.impl.persistence.entity.TimerJobEntity;
  
  /**
  
   */
  public class AcquireTimerJobsCmd implements Command<AcquiredTimerJobEntities> {
  
      private final AsyncExecutor asyncExecutor;
  
      public AcquireTimerJobsCmd(AsyncExecutor asyncExecutor) {
          this.asyncExecutor = asyncExecutor;
      }
  
      public AcquiredTimerJobEntities execute(CommandContext commandContext) {
          AcquiredTimerJobEntities acquiredJobs = new AcquiredTimerJobEntities();
          List<TimerJobEntity> timerJobs = commandContext
              .getTimerJobEntityManager()
              .findTimerJobsToExecute(new Page(0, asyncExecutor.getMaxAsyncJobsDuePerAcquisition()));
  
          for (TimerJobEntity job : timerJobs) {
              lockJob(commandContext, job, asyncExecutor.getAsyncJobLockTimeInMillis());
              acquiredJobs.addJob(job);
          }
  
          return acquiredJobs;
      }
  
      protected void lockJob(CommandContext commandContext, TimerJobEntity job, int lockTimeInMillis) {
          // This will trigger an optimistic locking exception when two concurrent executors
          // try to lock, as the revision will not match.
  
          GregorianCalendar gregorianCalendar = new GregorianCalendar();
          gregorianCalendar.setTime(commandContext.getProcessEngineConfiguration().getClock().getCurrentTime());
          gregorianCalendar.add(Calendar.MILLISECOND, lockTimeInMillis);
          job.setLockOwner(asyncExecutor.getLockOwner());
          job.setLockExpirationTime(gregorianCalendar.getTime());
      }
  }
  