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    1   /*
    2    *  Licensed to the Apache Software Foundation (ASF) under one
    3    *  or more contributor license agreements.  See the NOTICE file
    4    *  distributed with this work for additional information
    5    *  regarding copyright ownership.  The ASF licenses this file
    6    *  to you under the Apache License, Version 2.0 (the
    7    *  "License"); you may not use this file except in compliance
    8    *  with the License.  You may obtain a copy of the License at
    9    *
    10   *    http://www.apache.org/licenses/LICENSE-2.0
    11   *
    12   *  Unless required by applicable law or agreed to in writing,
    13   *  software distributed under the License is distributed on an
    14   *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    15   *  KIND, either express or implied.  See the License for the
    16   *  specific language governing permissions and limitations
    17   *  under the License.
    18   *
    19   */
    20  package org.apache.mina.transport.vmpipe;
    21
    22  import java.io.IOException;
    23  import java.net.SocketAddress;
    24  import java.util.HashSet;
    25  import java.util.Set;
    26  import java.util.concurrent.Executor;
    27
    28  import org.apache.mina.core.filterchain.IoFilterChain;
    29  import org.apache.mina.core.future.ConnectFuture;
    30  import org.apache.mina.core.future.DefaultConnectFuture;
    31  import org.apache.mina.core.future.IoFuture;
    32  import org.apache.mina.core.future.IoFutureListener;
    33  import org.apache.mina.core.service.AbstractIoConnector;
    34  import org.apache.mina.core.service.IoHandler;
    35  import org.apache.mina.core.service.TransportMetadata;
    36  import org.apache.mina.core.session.IdleStatusChecker;
    37  import org.apache.mina.core.session.IoSessionInitializer;
    38  import org.apache.mina.util.ExceptionMonitor;
    39
    40  /**
    41   * Connects to {@link IoHandler}s which is bound on the specified
    42   * {@link VmPipeAddress}.
    43   *
    44   * @author <a href="http://mina.apache.org">Apache MINA Project</a>
    45   */
    46  public final class VmPipeConnector extends AbstractIoConnector {
    47
    48      // object used for checking session idle
    49      private IdleStatusChecker idleChecker;
    50
    51      /**
    52       * Creates a new instance.
    53       */
    54      public VmPipeConnector() {
    55          this(null);
    56      }
    57
    58      /**
    59       * Creates a new instance.
    60       */
    61      public VmPipeConnector(Executor executor) {
    62          super(new DefaultVmPipeSessionConfig(), executor);
    63          idleChecker = new IdleStatusChecker();
    64          // we schedule the idle status checking task in this service exceutor
    65          // it will be woke up every seconds
    66          executeWorker(idleChecker.getNotifyingTask(), "idleStatusChecker");
    67      }
    68
    69      public TransportMetadata getTransportMetadata() {
    70          return VmPipeSession.METADATA;
    71      }
    72
    73      @Override
    74      public VmPipeSessionConfig getSessionConfig() {
    75          return (VmPipeSessionConfig) super.getSessionConfig();
    76      }
    77
    78      @Override
    79      protected ConnectFuture connect0(SocketAddress remoteAddress, SocketAddress localAddress,
    80              IoSessionInitializer<? extends ConnectFuture> sessionInitializer) {
    81          VmPipe entry = VmPipeAcceptor.boundHandlers.get(remoteAddress);
    82          if (entry == null) {
    83              return DefaultConnectFuture.newFailedFuture(new IOException("Endpoint unavailable: " + remoteAddress));
    84          }
    85
    86          DefaultConnectFuture future = new DefaultConnectFuture();
    87
    88          // Assign the local address dynamically,
    89          VmPipeAddress actualLocalAddress;
    90          try {
    91              actualLocalAddress = nextLocalAddress();
    92          } catch (IOException e) {
    93              return DefaultConnectFuture.newFailedFuture(e);
    94          }
    95
    96          VmPipeSession localSession = new VmPipeSession(this, getListeners(), actualLocalAddress, getHandler(), entry);
    97
    98          initSession(localSession, future, sessionInitializer);
    99
    100         // and reclaim the local address when the connection is closed.
    101         localSession.getCloseFuture().addListener(LOCAL_ADDRESS_RECLAIMER);
    102
    103         // initialize connector session
    104         try {
    105             IoFilterChain filterChain = localSession.getFilterChain();
    106             this.getFilterChainBuilder().buildFilterChain(filterChain);
    107
    108             // The following sentences don't throw any exceptions.
    109             getListeners().fireSessionCreated(localSession);
    110             idleChecker.addSession(localSession);
    111         } catch (Throwable t) {
    112             future.setException(t);
    113             return future;
    114         }
    115
    116         // initialize acceptor session
    117         VmPipeSession remoteSession = localSession.getRemoteSession();
    118         ((VmPipeAcceptor) remoteSession.getService()).doFinishSessionInitialization(remoteSession, null);
    119         try {
    120             IoFilterChain filterChain = remoteSession.getFilterChain();
    121             entry.getAcceptor().getFilterChainBuilder().buildFilterChain(filterChain);
    122
    123             // The following sentences don't throw any exceptions.
    124             entry.getListeners().fireSessionCreated(remoteSession);
    125             idleChecker.addSession(remoteSession);
    126         } catch (Throwable t) {
    127             ExceptionMonitor.getInstance().exceptionCaught(t);
    128             remoteSession.close(true);
    129         }
    130
    131         // Start chains, and then allow and messages read/written to be processed. This is to ensure that
    132         // sessionOpened gets received before a messageReceived
    133         ((VmPipeFilterChain) localSession.getFilterChain()).start();
    134         ((VmPipeFilterChain) remoteSession.getFilterChain()).start();
    135
    136         return future;
    137     }
    138
    139     @Override
    140     protected void dispose0() throws Exception {
    141         // stop the idle checking task
    142         idleChecker.getNotifyingTask().cancel();
    143     }
    144
    145     private static final Set<VmPipeAddress> TAKEN_LOCAL_ADDRESSES = new HashSet<VmPipeAddress>();
    146
    147     private static int nextLocalPort = -1;
    148
    149     private static final IoFutureListener<IoFuture> LOCAL_ADDRESS_RECLAIMER = new LocalAddressReclaimer();
    150
    151     private static VmPipeAddress nextLocalAddress() throws IOException {
    152         synchronized (TAKEN_LOCAL_ADDRESSES) {
    153             if (nextLocalPort >= 0) {
    154                 nextLocalPort = -1;
    155             }
    156             for (int i = 0; i < Integer.MAX_VALUE; i++) {
    157                 VmPipeAddress answer = new VmPipeAddress(nextLocalPort--);
    158                 if (!TAKEN_LOCAL_ADDRESSES.contains(answer)) {
    159                     TAKEN_LOCAL_ADDRESSES.add(answer);
    160                     return answer;
    161                 }
    162             }
    163         }
    164
    165         throw new IOException("Can't assign a local VM pipe port.");
    166     }
    167
    168     private static class LocalAddressReclaimer implements IoFutureListener<IoFuture> {
    169         public void operationComplete(IoFuture future) {
    170             synchronized (TAKEN_LOCAL_ADDRESSES) {
    171                 TAKEN_LOCAL_ADDRESSES.remove(future.getSession().getLocalAddress());
    172             }
    173         }
    174     }
    175 }