In what condition Spring call Lifecycle's start/stop hooks?

Question

I'm trying to understand the Lifecycle interface logic. The documentation for Lifecycle says:

Containers will propagate start/stop signals to all components that apply within each container, e.g. for a stop/restart scenario at runtime.

But it seems that cantainer doesn't call this methods (start/stop) at all.

For example the result for next code snippet is only single output ">> call: is running: false"

@Configuration
public class TestApp implements Lifecycle {

    boolean runStatus = false;

    @Override
    public void start() {
        System.err.println(">> call: start (Lifecycle)");
        runStatus = true;
    }

    @Override
    public void stop() {
        System.err.println(">> call: stop (Lifecycle)");
        runStatus = false;
    }

    @Override
    public boolean isRunning() {
        System.err.println(">> call: is running: " + runStatus);
        return runStatus;
    }

    public static void main(String[] args) {
        AbstractApplicationContext ctx = new AnnotationConfigApplicationContext(TestApp.class);
        ctx.stop();
    }
}

P.S. I heard about SmartLifecycle and it works fine. But I'm interesting in how can we correctly use the start/stop methods from Lifecycle.

Answer 1

You should manually start() and stop() the context.

@Configuration
 public class TestApp implements Lifecycle {

  boolean runStatus = false;

  public TestApp (){}


  @Bean
  public TestApp testApp(){
    return new TestApp();
  }

  @Override
  public void start() {
    System.err.println(">> call: start (Lifecycle)");
    runStatus = true;
  }

  @Override
  public void stop() {
    System.err.println(">> call: stop (Lifecycle)");
    runStatus = false;
  }

  @Override
  public boolean isRunning() {
    System.err.println(">> call: is running: " + runStatus);
    return runStatus;
  }

  public static void main(String[] args) {
    AbstractApplicationContext ctx = new AnnotationConfigApplicationContext(TestApp.class);
    ctx.start();
    TestApp ta = ctx.getBean(TestApp.class);
    ctx.stop();
  }
}