07.Quartz 监听器-TriggerListener

以你之姓@ 2022-02-20 04:37 334阅读 0赞

TriggerListner 用于监听触发器的相关创建, 用于在触发器触发前后做一些自定义操作. quartz 中TriggerListener的设计思想和JobListener 的设计思想如出一辙. 和JobListener 类似, quartz 2.x 也不再进行持久化操作.

## 1. TriggerListener 定义 ##

quartz 提供了两种方式自定义自己的TriggerListener, 一种是实现TriggerListener接口, 需要实现所有Listener 自定义的方法; 另一种是继承TriggerListenerSuppoer 类, 只需实现自己关注的方法即可.

### 1.1 TriggerListener 接口定义 ###

public interface TriggerListener { 
    
        // 返回trigger名称
        String getName();
    
        // 触发器触发时调用此方法
        void triggerFired(Trigger trigger, JobExecutionContext context);
    
        boolean vetoJobExecution(Trigger trigger, JobExecutionContext context);
    
        // 触发器触发,但是定时任务无法执行执行时调用此方法
        void triggerMisfired(Trigger trigger);
    
        // 触发器关联定时任务完成后调用此方法
        void triggerComplete(Trigger trigger, JobExecutionContext context, CompletedExecutionInstruction triggerInstructionCode);
    
    }

### 1.2 监听器匹配模式 ###

quartz 提供了Matcher 接口用于指定监听器匹配任务的模式, 可具体匹配的定时任务, 或按组进行屁, 亦或者匹配全部的定时任务

// 监听具体的一个触发器
    KeyMatcher<TriggerKey> keyMatcher = KeyMatcher.keyEquals(TriggerKey.triggerKey("triggerName1", "triggerGroupName"));
    
    // 监听一组触发器
    GroupMatcher<TriggerKey> groupMatcher = GroupMatcher.groupEquals("triggerGroupName");
    
    // 监听所有的触发器
    GroupMatcher<TriggerKey> allMatcher = GroupMatcher.anyJobGroup();

### 1.3 TriggerListener ###

# 1. 创建监听器匹配模式
     KeyMatcher<TriggerKey> keyMatcher = KeyMatcher.keyEquals(TriggerKey.triggerKey("triggerName1", "triggerGroup8"));
    
    # 2. 注册监听器
    scheduler.getListenerManager().addTriggerListener(new MyFirstTriggerListener(), keyMatcher);

## 2. 自定义TriggerListener ##

由于quartz 2.x 并不会对监听器做持久化操作, 因此笔者使用基于ram 配置的quartz环境.

### 2.1 实现TriggerListener接口 ###

必须实现TriggerListener 接口的所有方法,

public class MyFirstTriggerListener implements TriggerListener { 
        @Override
        public String getName() { 
            return "myFirstTriggerListener";
        }
    
        @Override
        public void triggerFired(Trigger trigger, JobExecutionContext context) { 
            System.out.println(getName() + "-triggerFired"  );
        }
    
        @Override
        public boolean vetoJobExecution(Trigger trigger, JobExecutionContext context) { 
            return false;
        }
    
        @Override
        public void triggerMisfired(Trigger trigger) { 
            System.out.println("first - triggerMisfired"+ trigger.getKey());
        }
    
        @Override
        public void triggerComplete(Trigger trigger, JobExecutionContext context, Trigger.CompletedExecutionInstruction triggerInstructionCode) { 
            System.out.println(getName() + "-triggerComplete");
        }
    }

### 2.2 继承TriggerListenerSupport ###

其实和实现TriggerListener接口无差异, getName()是必须重写的方法.

public class MySecondTriggerListener extends TriggerListenerSupport { 
    
        @Override
        public String getName() { 
            return "mySecondTriggerListener";
        }
    
        @Override
        public void triggerFired(Trigger trigger, JobExecutionContext context) { 
            System.out.println(getName() + "-triggerFired"  );
        }
    
        @Override
        public boolean vetoJobExecution(Trigger trigger, JobExecutionContext context) { 
            return false;
        }
    
        @Override
        public void triggerMisfired(Trigger trigger) { 
            System.out.println("first - triggerMisfired"+ trigger.getKey());
        }
    
        @Override
        public void triggerComplete(Trigger trigger, JobExecutionContext context, Trigger.CompletedExecutionInstruction triggerInstructionCode) { 
            System.out.println(getName() + "-triggerComplete");
        }
    }

### 2.3 测试用例 ###

笔者推荐在调度器启动之前添加任务监听器.

public class Test08 extends BaseQuartzRamTest { 
    
        // 测试trigger监听器
        @Test
        public void test_triggerListener() throws SchedulerException { 
    
            // 3. 创建定时任务
            JobDetail job = JobBuilder.newJob(ListenerJob.class)
                    .withIdentity("listenerJob", "jobGroup8")
                    .requestRecovery(true)
                    .build();
    
    
            // 4. 创建简单触发器
            Trigger trigger = TriggerBuilder.newTrigger()
                    .withIdentity("jobListenerTrigger", "triggerGroup8")
                    .startNow()
                    .withSchedule(SimpleScheduleBuilder.simpleSchedule()
                            .withRepeatCount(0))
                    .build();
    
            // 5. 将定时任务添加到调度队列中
            scheduler.scheduleJob(job, trigger);
    
    
            // 6. 笔者推荐在调度器启动之前添加监听器
            KeyMatcher<TriggerKey> keyMatcher = KeyMatcher.keyEquals(TriggerKey.triggerKey("jobListenerTrigger","triggerGroup8"));
            scheduler.getListenerManager().addTriggerListener(new MyFirstTriggerListener());
            scheduler.getListenerManager().addTriggerListener(new MySecondTriggerListener());
    
    
            // 7. 启动调度器
            scheduler.start();
    
        }
    
        // 重新启动之后, 并无监听. 说明quartz并不会持久化监听器
        @Test
        public void start() throws SchedulerException { 
            this.scheduler.start();
    
        }
    
    }

### 2.4 测试输出 ###

从输出结果来看, 可以发现执行步骤:

1.  执行监听器1 的triggerFired方法
2.  执行监听器2 的triggerFired方法
3.  执行定时任务的方法
4.  执行监听器2的triggerComplete的方法
5.  执行监听器1的triggerComplete的方法

myFirstTriggerListener-triggerFired
    mySecondTriggerListener-triggerFired
    2019-04-10T18:15:40.346-org.zongf.learn.quartz.l01.job.ListenerJob- do job...
    myFirstTriggerListener-triggerComplete
    mySecondTriggerListener-triggerComplete