geode-memcached/src/main/java/org/apache/geode/internal/memcached/ConnectionHandler.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more contributor license
 * agreements. See the NOTICE file distributed with this work for additional information regarding
 * copyright ownership. The ASF licenses this file to You 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.apache.geode.internal.memcached;

import java.io.IOException;
import java.net.Socket;
import java.nio.ByteBuffer;

import org.apache.geode.LogWriter;
import org.apache.geode.annotations.internal.MakeNotStatic;
import org.apache.geode.cache.Cache;
import org.apache.geode.cache.CacheClosedException;
import org.apache.geode.internal.memcached.commands.ClientError;
import org.apache.geode.memcached.GemFireMemcachedServer;
import org.apache.geode.memcached.GemFireMemcachedServer.Protocol;

/**
 * One instance of ConnectionHandle is created for each client that connects to
 * {@link GemFireMemcachedServer} and is responsible for reading requests and sending responses to
 * this client.
 *
 *
 *
 */
public class ConnectionHandler implements Runnable {

  private final Socket socket;

  private final Cache cache;

  private final Protocol protocol;

  @MakeNotStatic
  private static LogWriter logger;

  public ConnectionHandler(Socket socket, Cache cache, Protocol protocol) {
    this.socket = socket;
    this.cache = cache;
    this.protocol = protocol;
    if (logger == null) {
      logger = this.cache.getLogger();
    }
  }

  @Override
  public void run() {
    RequestReader request = new RequestReader(this.socket, this.protocol);
    while (!Thread.currentThread().isInterrupted()) {
      try {
        Command command = request.readCommand();
        if (logger.fineEnabled()) {
          logger.fine("processing command:" + command);
        }
        ByteBuffer reply =
            command.getCommandProcessor().processCommand(request, this.protocol, cache);
        if (reply != null) {
          request.sendReply(reply);
        }
        if (command == Command.QUIT || command == Command.QUITQ) {
          socket.close();
          break;
        }
      } catch (ClientError e) {
        request.sendException(e);
      } catch (IllegalArgumentException e) {
        // thrown by Command.valueOf() when there is no matching command
        request.sendException(e);
      } catch (CacheClosedException cc) {
        Thread.currentThread().interrupt();
      } catch (IOException e) {
        Thread.currentThread().interrupt();
      }
    }
    logger.fine("Connection handler " + Thread.currentThread().getName() + " terminating");
  }

  protected static LogWriter getLogger() {
    return logger;
  }
}