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   /*
    * Copyright 2012 The Netty Project
    *
    * The Netty Project 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 io.netty.bootstrap;
  
  import io.netty.channel.Channel;
  import io.netty.channel.ChannelFuture;
  import io.netty.channel.ChannelFutureListener;
  import io.netty.channel.ChannelOption;
  import io.netty.channel.ChannelPipeline;
  import io.netty.channel.ChannelPromise;
  import io.netty.channel.EventLoopGroup;
  import io.netty.util.AttributeKey;
  import io.netty.util.internal.logging.InternalLogger;
  import io.netty.util.internal.logging.InternalLoggerFactory;
  
  import java.net.InetAddress;
  import java.net.InetSocketAddress;
  import java.net.SocketAddress;
  import java.util.Map;
  import java.util.Map.Entry;
  
  /**
   * A {@link Bootstrap} that makes it easy to bootstrap a {@link Channel} to use
   * for clients.
   *
   * <p>The {@link #bind()} methods are useful in combination with connectionless transports such as datagram (UDP).
   * For regular TCP connections, please use the provided {@link #connect()} methods.</p>
   */
  public class Bootstrap extends AbstractBootstrap<Bootstrap, Channel> {
  
      private static final InternalLogger logger = InternalLoggerFactory.getInstance(Bootstrap.class);
  
      private volatile SocketAddress remoteAddress;
  
      public Bootstrap() { }
  
      private Bootstrap(Bootstrap bootstrap) {
          super(bootstrap);
          remoteAddress = bootstrap.remoteAddress;
      }
  
      /**
       * The {@link SocketAddress} to connect to once the {@link #connect()} method
       * is called.
       */
      public Bootstrap remoteAddress(SocketAddress remoteAddress) {
          this.remoteAddress = remoteAddress;
          return this;
      }
  
      /**
       * @see #remoteAddress(SocketAddress)
       */
      public Bootstrap remoteAddress(String inetHost, int inetPort) {
          remoteAddress = new InetSocketAddress(inetHost, inetPort);
          return this;
      }
  
      /**
       * @see #remoteAddress(SocketAddress)
       */
      public Bootstrap remoteAddress(InetAddress inetHost, int inetPort) {
          remoteAddress = new InetSocketAddress(inetHost, inetPort);
          return this;
      }
  
      /**
       * Connect a {@link Channel} to the remote peer.
       */
      public ChannelFuture connect() {
          validate();
          SocketAddress remoteAddress = this.remoteAddress;
          if (remoteAddress == null) {
              throw new IllegalStateException("remoteAddress not set");
          }
  
          return doConnect(remoteAddress, localAddress());
      }
  
      /**
       * Connect a {@link Channel} to the remote peer.
       */
      public ChannelFuture connect(String inetHost, int inetPort) {
          return connect(new InetSocketAddress(inetHost, inetPort));
      }
  
     /**
      * Connect a {@link Channel} to the remote peer.
      */
     public ChannelFuture connect(InetAddress inetHost, int inetPort) {
         return connect(new InetSocketAddress(inetHost, inetPort));
     }
 
     /**
      * Connect a {@link Channel} to the remote peer.
      */
     public ChannelFuture connect(SocketAddress remoteAddress) {
         if (remoteAddress == null) {
             throw new NullPointerException("remoteAddress");
         }
 
         validate();
         return doConnect(remoteAddress, localAddress());
     }
 
     /**
      * Connect a {@link Channel} to the remote peer.
      */
     public ChannelFuture connect(SocketAddress remoteAddress, SocketAddress localAddress) {
         if (remoteAddress == null) {
             throw new NullPointerException("remoteAddress");
         }
         validate();
         return doConnect(remoteAddress, localAddress);
     }
 
     /**
      * @see #connect()
      */
     private ChannelFuture doConnect(final SocketAddress remoteAddress, final SocketAddress localAddress) {
         final ChannelFuture regFuture = initAndRegister();
         final Channel channel = regFuture.channel();
         if (regFuture.cause() != null) {
             return regFuture;
         }
 
         final ChannelPromise promise = channel.newPromise();
         if (regFuture.isDone()) {
             doConnect0(regFuture, channel, remoteAddress, localAddress, promise);
         } else {
             regFuture.addListener(new ChannelFutureListener() {
                 @Override
                 public void operationComplete(ChannelFuture future) throws Exception {
                     doConnect0(regFuture, channel, remoteAddress, localAddress, promise);
                 }
             });
         }
 
         return promise;
     }
 
     private static void doConnect0(
             final ChannelFuture regFuture, final Channel channel,
             final SocketAddress remoteAddress, final SocketAddress localAddress, final ChannelPromise promise) {
 
         // This method is invoked before channelRegistered() is triggered.  Give user handlers a chance to set up
         // the pipeline in its channelRegistered() implementation.
         channel.eventLoop().execute(new Runnable() {
             @Override
             public void run() {
                 if (regFuture.isSuccess()) {
                     if (localAddress == null) {
                         channel.connect(remoteAddress, promise);
                     } else {
                         channel.connect(remoteAddress, localAddress, promise);
                     }
                     promise.addListener(ChannelFutureListener.CLOSE_ON_FAILURE);
                 } else {
                     promise.setFailure(regFuture.cause());
                 }
             }
         });
     }
 
     @Override
     @SuppressWarnings("unchecked")
     void init(Channel channel) throws Exception {
         ChannelPipeline p = channel.pipeline();
         p.addLast(handler());
 
         final Map<ChannelOption<?>, Object> options = options();
         synchronized (options) {
             setChannelOptions(channel, options, logger);
         }
 
         final Map<AttributeKey<?>, Object> attrs = attrs();
         synchronized (attrs) {
             for (Entry<AttributeKey<?>, Object> e: attrs.entrySet()) {
                 channel.attr((AttributeKey<Object>) e.getKey()).set(e.getValue());
             }
         }
     }
 
     @Override
     public Bootstrap validate() {
         super.validate();
         if (handler() == null) {
             throw new IllegalStateException("handler not set");
         }
         return this;
     }
 
     @Override
     @SuppressWarnings("CloneDoesntCallSuperClone")
     public Bootstrap clone() {
         return new Bootstrap(this);
     }
 
     /**
      * Returns a deep clone of this bootstrap which has the identical configuration except that it uses
      * the given {@link EventLoopGroup}. This method is useful when making multiple {@link Channel}s with similar
      * settings.
      */
     public Bootstrap clone(EventLoopGroup group) {
         Bootstrap bs = new Bootstrap(this);
         bs.group = group;
         return bs;
     }
 
     @Override
     public String toString() {
         if (remoteAddress == null) {
             return super.toString();
         }
 
         StringBuilder buf = new StringBuilder(super.toString());
         buf.setLength(buf.length() - 1);
 
         return buf.append(", remoteAddress: ")
                   .append(remoteAddress)
                   .append(')')
                   .toString();
     }
 }