/*
* ExecutorReactor.java February 2007
*
* Copyright (C) 2007, Niall Gallagher <niallg@users.sf.net>
*
* 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 org.simpleframework.transport.reactor;
import java.io.IOException;
import java.util.concurrent.Executor;
/**
* The <code>ExecutorReactor</code> is used to schedule operation for
* execution using an <code>Executor</code> implementation. This can be
* useful when the operations performed are time intensive. For example
* if the operations performed a read of the underlying channel and
* then had to parse the contents of the payload. Such operations would
* reduce the performance of the reactor if it could not delegate to
* some other form of executor, as it would delay their execution.
*
* @author Niall Gallagher
*/
public class ExecutorReactor implements Reactor {
/**
* This is used to distribute the ready operations for execution.
*/
private final OperationDistributor exchange;
/**
* This is used to execute the operations that ready to run.
*/
private final Executor executor;
/**
* Constructor for the <code>ExecutorReactor</code> object. This is
* used to create a reactor that can delegate to the executor. This
* also accepts the operations it is interested in, the value is
* taken from the <code>SelectionKey</code> object. A bit mask can
* be used to show interest in several operations at once.
*
* @param executor this is the executor used to run the operations
*/
public ExecutorReactor(Executor executor) throws IOException {
this(executor, 1);
}
/**
* Constructor for the <code>ExecutorReactor</code> object. This is
* used to create a reactor that can delegate to the executor. This
* also accepts the operations it is interested in, the value is
* taken from the <code>SelectionKey</code> object. A bit mask can
* be used to show interest in several operations at once.
*
* @param executor this is the executor used to run the operations
* @param count this is the number of distributors to be used
*/
public ExecutorReactor(Executor executor, int count) throws IOException {
this(executor, count, 120000);
}
/**
* Constructor for the <code>ExecutorReactor</code> object. This is
* used to create a reactor that can delegate to the executor. This
* also accepts the operations it is interested in, the value is
* taken from the <code>SelectionKey</code> object. A bit mask can
* be used to show interest in several operations at once.
*
* @param executor this is the executor used to run the operations
* @param count this is the number of distributors to be used
* @param expiry the length of time to maintain and idle operation
*/
public ExecutorReactor(Executor executor, int count, long expiry) throws IOException {
this.exchange = new PartitionDistributor(executor, count, expiry);
this.executor = executor;
}
/**
* This method is used to execute the provided operation without
* the need to specifically check for I/O events. This is used if
* the operation knows that the <code>SelectableChannel</code> is
* ready, or if the I/O operation can be performed without knowing
* if the channel is ready. Typically this is an efficient means
* to perform a poll rather than a select on the channel.
*
* @param task this is the task to execute immediately
*/
public void process(Operation task) throws IOException {
executor.execute(task);
}
/**
* This method is used to execute the provided operation when there
* is an I/O event that task is interested in. This will used the
* operations <code>SelectableChannel</code> object to determine
* the events that are ready on the channel. If this reactor is
* interested in any of the ready events then the task is executed.
*
* @param task this is the task to execute on interested events
* @param require this is the bit-mask value for interested events
*/
public void process(Operation task, int require) throws IOException {
exchange.process(task, require);
}
/**
* This is used to stop the reactor so that further requests to
* execute operations does nothing. This will clean up all of
* the reactors resources and unregister any operations that are
* currently awaiting execution. This should be used to ensure
* any threads used by the reactor gracefully stop.
*/
public void stop() throws IOException {
exchange.close();
}
}