如何在Camunda中捕获任务开始和结束的事件？

import org.camunda.bpm.engine.delegate.DelegateExecution;
import org.camunda.bpm.engine.delegate.ExecutionListener;

public class TaskEventListener implements ExecutionListener {

    @Override
    public void notify(DelegateExecution execution) throws Exception {
        String eventName = execution.getEventName();

        if ("start".equals(eventName)) {
            // 处理任务开始事件
            System.out.println("任务开始：" + execution.getCurrentActivityName());
        } else if ("end".equals(eventName)) {
            // 处理任务结束事件
            System.out.println("任务结束：" + execution.getCurrentActivityName());
        }
    }
}

<extensionElements>
  <camunda:executionListener class="com.example.TaskEventListener" event="start" />
  <camunda:executionListener class="com.example.TaskEventListener" event="end" />
</extensionElements>