ratpack.exec.ExecController Maven / Gradle / Ivy
/*
* Copyright 2014 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ratpack.exec;
import io.netty.channel.EventLoopGroup;
import ratpack.exec.internal.ThreadBinding;
import java.util.Optional;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.ScheduledExecutorService;
/**
* The exec controller manages the execution of operations.
*
* The instance for an application can be obtained via the server registry.
*/
public interface ExecController extends AutoCloseable {
/**
* Returns the execution controller bound to the current thread, if this is a Ratpack managed compute thread.
*
* If called on a non Ratpack compute thread, the returned optional will be empty.
*
* @return the execution controller for the current thread
*/
static Optional current() {
return ThreadBinding.get().map(ThreadBinding::getExecController);
}
/**
* Returns the execution controller bound to the current thread, or throws an exception if called on a non Ratpack managed compute thread.
*
* If called on a non Ratpack compute thread, the returned optional will be empty.
*
* @return the execution controller for the current thread
* @throws UnmanagedThreadException when called from a non Ratpack managed thread
*/
static ExecController require() throws UnmanagedThreadException {
return current().orElseThrow(UnmanagedThreadException::new);
}
ExecStarter fork();
/**
* The event loop (i.e. computation) executor.
*
* This executor wraps Netty's event loop executor to provide callback features by way of Guava's executor extensions.
*
* It is generally preferable to use {@link #fork()} to submit computation work rather than this method,
* which properly initialises Ratpack's execution infrastructure.
*
* @return the executor that performs computation
*/
ScheduledExecutorService getExecutor();
ExecutorService getBlockingExecutor();
/**
* The event loop group used by Netty for this application.
*
* Generally there is no need to access this unless you are doing something directly with Netty.
*
* @return the event loop group
*/
EventLoopGroup getEventLoopGroup();
/**
* The number of threads that will be used for computation.
*
* This is determined by the {@link ratpack.server.ServerConfig#getThreads()} value of the launch config that created this controller.
*
* @return the number of threads that will be used for computation
*/
int getNumThreads();
/**
* Shuts down this controller, terminating the event loop and blocking threads.
*
* This method returns immediately, not waiting for the actual shutdown to occur.
*
* Generally, the only time it is necessary to call this method is when using an exec controller directly during testing.
* Calling {@link ratpack.server.RatpackServer#stop()} will inherently call this method.
*/
@Override
void close();
}