Spring源码-LifecycleProcessor

使用方法

Lifecycle:容器的生命周期回调，容器启动之后运行到某些节点（容器start/stop时候）可以回调Lifecycle子类的方法。比如在容器启动后初始化资源池，在容器停止时候调用资源池销毁的动作

我们实现Lifecycle中接口。注：建议实现SmartLifecycle接口，因为它Lifecycle接口的加强接口，默认实现了stop(Runnable callback)，在调用中通过一个CountdownLatch来异步处理stop,SmartLifecycle非常不建议实现stop(Runnable callback)方法

  public interface Lifecycle {
    void start();
    void stop();
    boolean isRunning();
}

public interface Phased {  
  int getPhase();  
}

public interface SmartLifecycle extends Lifecycle, Phased {  
  default boolean isAutoStartup() {
    return true;
  }

  default void stop(Runnable callback) {
    stop();
    callback.run();
  }

  default int getPhase() {
    return DEFAULT_PHASE;
  }
}

在Lifecycle的基础上实现了onRefresh和onClose接口。参见前面：Spring源码-ApplicationContext文章中finishRefresh中的代码片段。onRefresh会调用Lifecycle实现类的start()方法

// Initialize lifecycle processor for this context.
//初始化LifecycleProcessor
initLifecycleProcessor();

// Propagate refresh to lifecycle processor first.
//调用上面的LifecycleProcessor.onRefresh()
getLifecycleProcessor().onRefresh();

public interface LifecycleProcessor extends Lifecycle {  
  void onRefresh();  
  void onClose();  
}

调用流程

tbd