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 org.activiti.engine.ActivitiTaskAlreadyClaimedException;
  import org.activiti.engine.impl.interceptor.CommandContext;
  import org.activiti.engine.impl.persistence.entity.TaskEntity;
  
  /**
  
   */
  public class ClaimTaskCmd extends NeedsActiveTaskCmd<Void> {
  
      private static final long serialVersionUID = 1L;
  
      protected String userId;
  
      public ClaimTaskCmd(String taskId, String userId) {
          super(taskId);
          this.userId = userId;
      }
  
      protected Void execute(CommandContext commandContext, TaskEntity task) {
          if (userId != null) {
              task.setClaimTime(commandContext.getProcessEngineConfiguration().getClock().getCurrentTime());
  
              if (task.getAssignee() != null) {
                  if (!task.getAssignee().equals(userId)) {
                      // When the task is already claimed by another user, throw
                      // exception. Otherwise, ignore
                      // this, post-conditions of method already met.
                      throw new ActivitiTaskAlreadyClaimedException(task.getId(), task.getAssignee());
                  }
              } else {
                  commandContext.getTaskEntityManager().changeTaskAssignee(task, userId);
              }
          } else {
              // Task claim time should be null
              task.setClaimTime(null);
  
              // Task should be assigned to no one
              commandContext.getTaskEntityManager().changeTaskAssignee(task, null);
          }
  
          // Add claim time to historic task instance
          commandContext.getHistoryManager().recordTaskClaim(task);
  
          return null;
      }
  
      @Override
      protected String getSuspendedTaskException() {
          return "Cannot claim a suspended task";
      }
  }
  