How to manually shutdown embedded Tomcat? - spring-boot

I'm trying to implement a graceful shutdown sequence for my Spring Boot application. For that I registered a custom shutdown hook with Runtime and disabled the one provided by Spring (SpringApplication.setRegisterShutdownHook(false)). From this custom shutdown hook I first would like to pause embedded Tomcat or the connectors and some other schedulers after which I manually invoke applicationContext.close() to shutdown the rest of the Spring application.
What is the best way to get access to the embedded Tomcat instance? I was fiddling around with TomcatEmbeddedServletContainerFactory but this does not seem to give me access to default connectors or EmbeddedServletContainer which has a stop method.

You can access the EmbeddedServletContainer from the EmbeddedWebApplicationContext (just inject that) and downcast it.

Related

Spring Kafka Listener shutdown Application

I have an application that creates 3 KafkaListener per configuration in the ConcurrentKafkaListenerContainerFactory if any of these Listeners throws a specific Exception. I would like to shutdown the entire spring application.
Since these errors are non recoverable and need manual intervention.
How would i go about doin this?
Do i just inject the ApplicationContext into the Listener and close the application from there?
Or is there a more appropriate way of handling this?
That's one way, or you could just call System.exit(1).

spring-boot graceful shutdown

Is there a way in spring boot to control the graceful shutdown of the app.
I know that you can have #PreDestroy methods in beans but how can you control the ordering in which those #PreDestroy methods are called.
You can have multiple beans depending on each other will the shutdown of the context look for this dependency already and call the #PreDestroy methods in the right order or not?
For example what I would like to accomplish is:
1.) stop listening for new requests on rest endpoints
2.) prevent rabbit message listeners to accept new messages
3.) wait for all processing that has started before the shutdown but is not finished yet.
Spring-boot-2-3-0 has added support for graceful shutdown.
you can enable graceful shutdown by setting up server.shutdown=graceful property
To configure the timeout period you can use
spring.lifecycle.timeout-per-shutdown-phase=20s
spring boot documentation
If you can not upgrade to spring boot 2.3 then you can check below project
https://github.com/gesellix/graceful-shutdown-spring-boot

How to gracefully shutdown a Spring Boot application?

Is there any difference between springapplication.registerShutdownhook() () and Springapplication.exit(applicationcontext) ? Will either of them also shut down the JVM gracefully?
If you have a ConfigurableApplicationContext, you can use the method registerShutdownHook() to register a shutdown hook with the JVM runtime. You can see more here.
http://docs.oracle.com/javase/8/docs/api/java/lang/Runtime.html?is-external=true#addShutdownHook-java.lang.Thread-
You use Springapplication.exit(applicationcontext) to close the application context an finish the Spring application.

how can we use addShutdownHook in project?

i saw some code use ShutdownHook like this
Runtime.getRuntime().addShutdownHook(new Thread(){
ConfigurableApplicationContext.stop();
//close spring context;
threadpool.shutdownnow();
//close theadpool
});
is there anything useful to do like this?
i thought
when jvm exit ,maybe thread will be shutdown immediately
and spring context will close tooï¼›
what shall we do next when we need to call System.exit() ?
It really depends on your application and the lifecycle of your objects and those threads you appear to have outside of your context. If you are running the spring container inside a standalone java process, then trapping the shutdown hook like this is one way to do that. Another way is to have it listen on a tcp port and send a command to begin the shutdown process. If you are running in a web container like tomcat, then you should follow the standards on normal webapp shutdown, which Spring supports with Context Listeners.
I would also consider redesigning your app so that the threads are all managed with a bean that lives inside your spring container. For instance using a bean that is configured with directives (attributes) for start/stop methods and then that bean would use an Executor for thread pooling. This way, your shutdown is ONLY shutting down the Spring container, and Spring provides very good support for orderly shutdown of beans. One of those beans is your object holding the threads within the Executor. Its a much cleaner way than trying to integrate Spring beans with external threads.
Hope this helps.

Gracefull shutdown on Jboss server 7

I have a scenario where i need to perform a gracefull shutdown on Jboss server 7 where my application needs to flush out all Objects from My application with proper logging and deleting out all the active session containing in my application . I am using spring 3.0 is there any thing provided by spring framework for this
You could implement an ApplicationListener or use a servlet context lifecycle listener instead:
Application context event handling
Servlet context event handling

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