com.yahoo.jdisc.application.Application Maven / Gradle / Ivy
// Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
package com.yahoo.jdisc.application;
import com.yahoo.jdisc.Container;
import com.yahoo.jdisc.core.ApplicationLoader;
import com.yahoo.jdisc.service.ClientProvider;
import com.yahoo.jdisc.service.ServerProvider;
/**
* This interface defines the API of the singleton Application that runs in a jDISC instance. An Application instance
* will always have its {@link #destroy()} method called, regardless of whether {@link #start()} or {@link #stop()}
* threw any exceptions.
*
* @author Simon Thoresen Hult
*/
public interface Application {
/**
* This method is called by the {@link ApplicationLoader} just after creating this Application instance. Use this
* method to start the Application's worker thread, and to activate a {@link Container}. If you attempt to call
* {@link ContainerActivator#activateContainer(ContainerBuilder)} before this method is invoked, that call will
* throw an {@link ApplicationNotReadyException}. If this method does not throw an exception, the {@link #stop()}
* method will be called at some time in the future.
*/
void start();
/**
* This method is called by the {@link ApplicationLoader} after the corresponding signal has been issued by the
* controlling start script. Once this method returns, all calls to {@link
* ContainerActivator#activateContainer(ContainerBuilder)} will throw {@link ApplicationNotReadyException}s. Use
* this method to prepare for termination (see {@link #destroy()}).
*/
void stop();
/**
* This method is called by the {@link ApplicationLoader} after first calling {@link #stop()}, and all previous
* {@link DeactivatedContainer}s have terminated. Use this method to shut down all Application components such as
* {@link ClientProvider}s and {@link ServerProvider}s.
*/
void destroy();
}