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    1   /*
    2    * Copyright 2009 Red Hat, Inc.
    3    *
    4    * Red Hat licenses this file to you under the Apache License, version 2.0
    5    * (the "License"); you may not use this file except in compliance with the
    6    * License.  You may obtain a copy of the License at:
    7    *
    8    *    http://www.apache.org/licenses/LICENSE-2.0
    9    *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
    12   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
    13   * License for the specific language governing permissions and limitations
    14   * under the License.
    15   */
    16  package org.jboss.netty.example.uptime;
    17
    18  import java.net.ConnectException;
    19  import java.net.InetSocketAddress;
    20  import java.util.concurrent.TimeUnit;
    21
    22  import org.jboss.netty.bootstrap.ClientBootstrap;
    23  import org.jboss.netty.channel.ChannelHandlerContext;
    24  import org.jboss.netty.channel.ChannelStateEvent;
    25  import org.jboss.netty.channel.ExceptionEvent;
    26  import org.jboss.netty.channel.SimpleChannelUpstreamHandler;
    27  import org.jboss.netty.util.Timeout;
    28  import org.jboss.netty.util.Timer;
    29  import org.jboss.netty.util.TimerTask;
    30
    31  /**
    32   * Keep reconnecting to the server while printing out the current uptime and
    33   * connection attempt status.
    34   *
    35   * @author <a href="http://www.jboss.org/netty/">The Netty Project</a>
    36   * @author <a href="http://gleamynode.net/">Trustin Lee</a>
    37   *
    38   * @version $Rev: 2189 $, $Date: 2010-02-19 18:02:57 +0900 (Fri, 19 Feb 2010) $
    39   */
    40  public class UptimeClientHandler extends SimpleChannelUpstreamHandler {
    41
    42      final ClientBootstrap bootstrap;
    43      private final Timer timer;
    44      private long startTime = -1;
    45
    46      public UptimeClientHandler(ClientBootstrap bootstrap, Timer timer) {
    47          this.bootstrap = bootstrap;
    48          this.timer = timer;
    49      }
    50
    51      InetSocketAddress getRemoteAddress() {
    52          return (InetSocketAddress) bootstrap.getOption("remoteAddress");
    53      }
    54
    55      @Override
    56      public void channelDisconnected(ChannelHandlerContext ctx, ChannelStateEvent e) {
    57          println("Disconnected from: " + getRemoteAddress());
    58      }
    59
    60      @Override
    61      public void channelClosed(ChannelHandlerContext ctx, ChannelStateEvent e) {
    62          println("Sleeping for: " + UptimeClient.RECONNECT_DELAY + "s");
    63          timer.newTimeout(new TimerTask() {
    64              public void run(Timeout timeout) throws Exception {
    65                  println("Reconnecting to: " + getRemoteAddress());
    66                  bootstrap.connect();
    67              }
    68          }, UptimeClient.RECONNECT_DELAY, TimeUnit.SECONDS);
    69      }
    70
    71      @Override
    72      public void channelConnected(ChannelHandlerContext ctx, ChannelStateEvent e) {
    73          if (startTime < 0) {
    74              startTime = System.currentTimeMillis();
    75          }
    76
    77          println("Connected to: " + getRemoteAddress());
    78      }
    79
    80      @Override
    81      public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) {
    82          Throwable cause = e.getCause();
    83          if (cause instanceof ConnectException) {
    84              startTime = -1;
    85              println("Failed to connect: " + cause.getMessage());
    86          }
    87          ctx.getChannel().close();
    88      }
    89
    90      void println(String msg) {
    91          if (startTime < 0) {
    92              System.err.format("[SERVER IS DOWN] %s%n", msg);
    93          } else {
    94              System.err.format("[UPTIME: %5ds] %s%n", (System.currentTimeMillis() - startTime) / 1000, msg);
    95          }
    96      }
    97  }