Activiti监听器

学习链接

Activiti深入研究 - 专栏

• 5.2 activiti任务监听器TaskListener
• 5.1 activiti执行监听器ExecutionListener
• 5.3 activiti工作流程事件监听ActivitiEventListener

Activiti7工作流从入门到实战(全网最好的)

• Activiti7工作流引擎：基础篇(六) 任务监听器和流程监听器

Activiti

• activiti学习（五）——执行监听器与任务监听器的基本使用
• activiti学习（十一）——全局事件监听器的基本使用及其原理

程序员一灯-activiti监听器

任务监听器 TaskListener

任务监听器用于在特定的任务相关事件发生时，执行自定义的Java逻辑或表达式

• 任务监听器是处理业务逻辑的重要的地方，当任务创建、设定负责人、完成任务时都可以监听的到，从而来处理自己的业务
• 常用于监听Assignment事件，设置完负责人给负责人发一个消息来通知提示。注意：任务监听器只能用在UserTask上使用。

监听器监听的事件

• String EVENTNAME_CREATE = “create”;创建）：当任务已经创建，并且所有任务参数都已经设置时触发

• String EVENTNAME_ASSIGNMENT = “assignment”;（指派）：当任务已经指派给某人时触发。请注意：当流程执行到达用户任务时，create事件触发前，首先触发assignment事件。这看起来不是自然顺序，但是有实际原因的：当收到create事件时，我们通常希望查看任务的所有参数，包括办理人。

• String EVENTNAME_COMPLETE = “complete”（完成）：当任务已经完成，从运行时数据中删除前触发。

• String EVENTNAME_DELETE = “delete”（删除）：在任务即将被删除前触发。请注意当任务通过completeTask正常完成时也会触发

注意：assignment事件比create先执行。

监听器委托类DelegateTask

我们在监听方法中，能够拿到DelegateTask对象，因此，我们要熟悉这个对象的相关方法

package org.activiti.engine.delegate;
 
import java.util.Collection;
import java.util.Date;
import java.util.Set;
 
import org.activiti.engine.ActivitiObjectNotFoundException;
import org.activiti.engine.task.DelegationState;
import org.activiti.engine.task.IdentityLink;
import org.activiti.engine.task.IdentityLinkType;
 
/**
 * @author Joram Barrez
 */
public interface DelegateTask extends VariableScope {
 
  /** DB id of the task. */
  String getId();
  
  /** Name or title of the task. */
  String getName();
  
  /** Change the name of the task. */
  void setName(String name);
 
  /** Free text description of the task. */
  String getDescription();
  
  /** Change the description of the task */
  void setDescription(String description);
  
  /** indication of how important/urgent this task is with a number between 
   * 0 and 100 where higher values mean a higher priority and lower values mean 
   * lower priority: [0..19] lowest, [20..39] low, [40..59] normal, [60..79] high 
   * [80..100] highest */
  int getPriority();
  
  /** indication of how important/urgent this task is with a number between 
   * 0 and 100 where higher values mean a higher priority and lower values mean 
   * lower priority: [0..19] lowest, [20..39] low, [40..59] normal, [60..79] high 
   * [80..100] highest */
  void setPriority(int priority);
  
  /** Reference to the process instance or null if it is not related to a process instance. */
  String getProcessInstanceId();
  
  /** Reference to the path of execution or null if it is not related to a process instance. */
  String getExecutionId();
  
  /** Reference to the process definition or null if it is not related to a process. */
  String getProcessDefinitionId();
 
  /** The date/time when this task was created */
  Date getCreateTime();
  
  /** The id of the activity in the process defining this task or null if this is not related to a process */
  String getTaskDefinitionKey();
 
  /** Indicated whether this task is suspended or not. */
  boolean isSuspended();
 
  /** The tenant identifier of this task */
  String getTenantId();
 
  /** The form key for the user task */
  String getFormKey();
 
  /** Change the form key of the task */
  void setFormKey(String formKey);
  
  /** Returns the execution currently at the task. */
  DelegateExecution getExecution();
  
  /** Returns the event name which triggered the task listener to fire for this task. */
  String getEventName();
 
  /** The current {@link org.activiti.engine.task.DelegationState} for this task. */
  DelegationState getDelegationState();
  
  /** Adds the given user as a candidate user to this task. */
  void addCandidateUser(String userId);
  
  /** Adds multiple users as candidate user to this task. */
  void addCandidateUsers(Collection<String> candidateUsers);
  
  /** Adds the given group as candidate group to this task */
  void addCandidateGroup(String groupId);
  
  /** Adds multiple groups as candidate group to this task. */
  void addCandidateGroups(Collection<String> candidateGroups);
 
  /** The {@link User.getId() userId} of the person responsible for this task. */
  String getOwner();
  
  /** The {@link User.getId() userId} of the person responsible for this task.*/
  void setOwner(String owner);
  
  /** The {@link User.getId() userId} of the person to which this task is delegated. */
  String getAssignee();
  
  /** The {@link User.getId() userId} of the person to which this task is delegated. */
  void setAssignee(String assignee);
  
  /** Due date of the task. */
  Date getDueDate();
  
  /** Change due date of the task. */
  void setDueDate(Date dueDate);
  
  /** The category of the task. This is an optional field and allows to 'tag' tasks as belonging to a certain category. */
  String getCategory();
	
  /** Change the category of the task. This is an optional field and allows to 'tag' tasks as belonging to a certain category. */
  void setCategory(String category);
  
  /**
   * Involves a user with a task. The type of identity link is defined by the given identityLinkType.
   * @param userId id of the user involve, cannot be null.
   * @param identityLinkType type of identityLink, cannot be null (@see {@link IdentityLinkType}).
   * @throws ActivitiObjectNotFoundException when the task or user doesn't exist.
   */
  void addUserIdentityLink(String userId, String identityLinkType);
  
  /**
   * Involves a group with group task. The type of identityLink is defined by the given identityLink.
   * @param groupId id of the group to involve, cannot be null.
   * @param identityLinkType type of identity, cannot be null (@see {@link IdentityLinkType}).
   * @throws ActivitiObjectNotFoundException when the task or group doesn't exist.
   */
  void addGroupIdentityLink(String groupId, String identityLinkType);
  
  /**
   * Convenience shorthand for {@link #deleteUserIdentityLink(String, String)}; with type {@link IdentityLinkType#CANDIDATE}
   * @param userId id of the user to use as candidate, cannot be null.
   * @throws ActivitiObjectNotFoundException when the task or user doesn't exist.
   */
  void deleteCandidateUser(String userId);
  
  /**
   * Convenience shorthand for {@link #deleteGroupIdentityLink(String, String, String)}; with type {@link IdentityLinkType#CANDIDATE}
   * @param groupId id of the group to use as candidate, cannot be null.
   * @throws ActivitiObjectNotFoundException when the task or group doesn't exist.
   */
  void deleteCandidateGroup(String groupId);
  
  /**
   * Removes the association between a user and a task for the given identityLinkType.
   * @param userId id of the user involve, cannot be null.
   * @param identityLinkType type of identityLink, cannot be null (@see {@link IdentityLinkType}).
   * @throws ActivitiObjectNotFoundException when the task or user doesn't exist.
   */
  void deleteUserIdentityLink(String userId, String identityLinkType);
  
  /**
   * Removes the association between a group and a task for the given identityLinkType.
   * @param groupId id of the group to involve, cannot be null.
   * @param identityLinkType type of identity, cannot be null (@see {@link IdentityLinkType}).
   * @throws ActivitiObjectNotFoundException when the task or group doesn't exist.
   */
  void deleteGroupIdentityLink(String groupId, String identityLinkType);
 
  /**
   * Retrieves the candidate users and groups associated with the task.
   * @return set of {@link IdentityLink}s of type {@link IdentityLinkType#CANDIDATE}.
   */
  Set<IdentityLink> getCandidates();
}

任务监听实现方式 — 类class

绘制流程图

给经理审批节点设置如下任务监听器

自定义任务监听器

SiteReportUserTaskListener

import lombok.extern.slf4j.Slf4j;
import org.activiti.engine.delegate.DelegateTask;
import org.activiti.engine.delegate.TaskListener;

/**
 * 任务监听器用于在特定的任务相关事件发生时，执行自定义的Java逻辑或表达式
 *
 * 任务监听器支持下列属性：
 *  event（事件）（必填）：任务监听器将被调用的任务事件类型。可用的事件有：
 *         create（创建）：当任务已经创建，并且所有任务参数都已经设置时触发。
 *         assignment（指派）：当任务已经指派给某人时触发。请注意：当流程执行到达用户任务时，create事件触发前，首先触发
 *         assignment事件。这看起来不是自然顺序，但是有实际原因的：当收到create事件时，我们通常希望查看任务的所有参数，包括
 *         办理人。
 *         complete（完成）：当任务已经完成，从运行时数据中删除前触发。
 *         delete（删除）：在任务即将被删除前触发。请注意当任务通过completeTask正常完成时也会触发
 *
 *   class：需要调用的代理类。这个类必须实现 org.activiti.engine.delegate.TaskListener 接口
 *
 *
 *   expression：（不能与class属性一起使用）：指定在事件发生时要执行的表达式。可以为被调用的对象传递 DelegateTask 对象与事件名（使用 task.eventName ）作为参数
 *
 *
 *
 *   delegateExpression：可以指定一个能够解析为 TaskListener 接口实现类对象的表达式。与服务任务类似
 *
 *
 */
@Slf4j
public class SiteReportUserTaskListener implements TaskListener {

    /*
      启动流程时候（按顺序）
        收到事件通知: assignment
        收到事件通知: create
      完成经理审批任务时候（按顺序）
        收到事件通知: complete
        收到事件通知: delete
    */
    @Override
    public void notify(DelegateTask delegateTask) {
        log.info("收到事件通知: {}", delegateTask.getEventName());
    }


}

测试

1. 先部署该流程
2. 然后，发起1个流程时，它会收到assignment、create
3. 然后，部门经理完成该任务，它会收到complete、delete

监听实现方式 — 表达式expression

使用activiti:taskListener元素的expression属性来指定监听器

绘制流程图

自定义 TaskListenerExpression

@Slf4j
public class TaskListenerExpression implements Serializable {

    public void execute(DelegateTask delegateTask) {
        log.info("收到事件通知: {}", delegateTask.getEventName());
    }

}

测试

1. 先部署该流程

2. 然后，发起1个流程时，注意发起流程时，这里需要设置taskListenerExpression，然后它会收到assignment、create

   // 在流程执行到某个阶段，或者启动流程实例的时候，用下面代码调用
   HashMap<String, Object> variables = new HashMap<String, Object>();
   variables.put("taskListenerExpression", new TaskListenerExpression());
   ProcessInstance processInstance = runtimeService.startProcessInstanceByKey("listener1", variables);
   

3. 然后，部门经理完成该任务，它会收到complete、delete

spring表达式

在上面，我们在开启流程时，自己new了1个TaskListenerExpression，并且把它放入了流程变量中。在spring中，我们只需要将此bean定义在spring容器中即可，在启动流程时，不需要把它放入流程变量中，就可以启动流程了（注意：一定要把这个bean定义在容器中，否则会报错）。

执行监听器 ExecutionListener

工作流程事件监听 ActivitiEventListener