SecureNegotiator.java

/*
 * SecureNegotiator.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;

import java.io.IOException;

import org.simpleframework.transport.reactor.ExecutorReactor;
import org.simpleframework.transport.reactor.Operation;
import org.simpleframework.transport.reactor.Reactor;
import org.simpleframework.util.thread.PoolExecutor;

/**
 * The <code>SecureNegotiator</code> object is used to negotiations to complete
 * SSL handshakes for secure connections. Negotiations are performed on
 * <code>Pipeline</code> object before a transport is created from the pipeline.
 * Performing the SSL handshake is required to ensure that only HTTP specific
 * data is read and written to the underlying transport.
 * 
 * @author Niall Gallagher
 */
class SecureNegotiator implements Negotiator {

    /**
     * This is the transport used to process complete transports.
     */
    private final Processor transporter;

    /**
     * This is the executor used to execute the negotiations.
     */
    private final PoolExecutor executor;

    /**
     * This is the reactor which is used to schedule I/O events.
     */
    private final Reactor reactor;

    /**
     * Constructor for the <code>SecureNegotiator</code> object. This is used to
     * create a negotiator that will perform SSL handshakes on provided
     * pipelines so that the data read from an written to the underlying
     * transport is complete and ready to use.
     * 
     * @param transporter
     *            this is used to process the transports
     * @param count
     *            this is the number of threads used by this
     */
    public SecureNegotiator(Processor transporter, int count)
            throws IOException {
        this.executor = new PoolExecutor(Notifier.class, count);
        this.reactor = new ExecutorReactor(this.executor);
        this.transporter = transporter;
    }

    /**
     * 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
     */
    @Override
    public void process(Operation task) throws IOException {
        this.reactor.process(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 bitmask value for interested events
     */
    @Override
    public void process(Operation task, int require) throws IOException {
        this.reactor.process(task, require);
    }

    /**
     * Once the negotiation has completed this is used to perform processing of
     * the provided transport. Processing of the transport is done only after
     * the negotiation has completed. The given transport is used to read and
     * write to the socket.
     * 
     * @param transport
     *            this is the transport for the pipeline
     */
    @Override
    public void process(Transport transport) throws IOException {
        this.transporter.process(transport);
    }

    /**
     * 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.
     */
    @Override
    public void stop() throws IOException {
        this.executor.stop();
        this.reactor.stop();
    }
}