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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.handler.codec.serialization;
17  
18  import java.io.DataOutputStream;
19  import java.io.IOException;
20  import java.io.ObjectOutput;
21  import java.io.ObjectOutputStream;
22  import java.io.OutputStream;
23  
24  import org.jboss.netty.buffer.ChannelBuffer;
25  import org.jboss.netty.buffer.ChannelBufferOutputStream;
26  import org.jboss.netty.buffer.ChannelBuffers;
27  
28  /**
29   * An {@link ObjectOutput} which is interoperable with {@link ObjectDecoder}
30   * and {@link ObjectDecoderInputStream}.
31   *
32   * @author <a href="http://www.jboss.org/netty/">The Netty Project</a>
33   * @author <a href="http://gleamynode.net/">Trustin Lee</a>
34   *
35   * @version $Rev: 2080 $, $Date: 2010-01-26 18:04:19 +0900 (Tue, 26 Jan 2010) $
36   *
37   */
38  public class ObjectEncoderOutputStream extends OutputStream implements
39          ObjectOutput {
40  
41      private final DataOutputStream out;
42      private final int estimatedLength;
43  
44      /**
45       * Creates a new {@link ObjectOutput} with the estimated length of 512
46       * bytes.
47       *
48       * @param out
49       *        the {@link OutputStream} where the serialized form will be
50       *        written out
51       */
52      public ObjectEncoderOutputStream(OutputStream out) {
53          this(out, 512);
54      }
55  
56      /**
57       * Creates a new {@link ObjectOutput}.
58       *
59       * @param out
60       *        the {@link OutputStream} where the serialized form will be
61       *        written out
62       *
63       * @param estimatedLength
64       *        the estimated byte length of the serialized form of an object.
65       *        If the length of the serialized form exceeds this value, the
66       *        internal buffer will be expanded automatically at the cost of
67       *        memory bandwidth.  If this value is too big, it will also waste
68       *        memory bandwidth.  To avoid unnecessary memory copy or allocation
69       *        cost, please specify the properly estimated value.
70       */
71      public ObjectEncoderOutputStream(OutputStream out, int estimatedLength) {
72          if (out == null) {
73              throw new NullPointerException("out");
74          }
75          if (estimatedLength < 0) {
76              throw new IllegalArgumentException("estimatedLength: " + estimatedLength);
77          }
78  
79          if (out instanceof DataOutputStream) {
80              this.out = (DataOutputStream) out;
81          } else {
82              this.out = new DataOutputStream(out);
83          }
84          this.estimatedLength = estimatedLength;
85      }
86  
87      public void writeObject(Object obj) throws IOException {
88          ChannelBufferOutputStream bout = new ChannelBufferOutputStream(
89                  ChannelBuffers.dynamicBuffer(estimatedLength));
90          ObjectOutputStream oout = new CompactObjectOutputStream(bout);
91          oout.writeObject(obj);
92          oout.flush();
93          oout.close();
94  
95          ChannelBuffer buffer = bout.buffer();
96          int objectSize = buffer.readableBytes();
97          writeInt(objectSize);
98          buffer.getBytes(0, this, objectSize);
99      }
100 
101     @Override
102     public void write(int b) throws IOException {
103         out.write(b);
104     }
105 
106     @Override
107     public void close() throws IOException {
108         out.close();
109     }
110 
111     @Override
112     public void flush() throws IOException {
113         out.flush();
114     }
115 
116     public final int size() {
117         return out.size();
118     }
119 
120     @Override
121     public void write(byte[] b, int off, int len) throws IOException {
122         out.write(b, off, len);
123     }
124 
125     @Override
126     public void write(byte[] b) throws IOException {
127         out.write(b);
128     }
129 
130     public final void writeBoolean(boolean v) throws IOException {
131         out.writeBoolean(v);
132     }
133 
134     public final void writeByte(int v) throws IOException {
135         out.writeByte(v);
136     }
137 
138     public final void writeBytes(String s) throws IOException {
139         out.writeBytes(s);
140     }
141 
142     public final void writeChar(int v) throws IOException {
143         out.writeChar(v);
144     }
145 
146     public final void writeChars(String s) throws IOException {
147         out.writeChars(s);
148     }
149 
150     public final void writeDouble(double v) throws IOException {
151         out.writeDouble(v);
152     }
153 
154     public final void writeFloat(float v) throws IOException {
155         out.writeFloat(v);
156     }
157 
158     public final void writeInt(int v) throws IOException {
159         out.writeInt(v);
160     }
161 
162     public final void writeLong(long v) throws IOException {
163         out.writeLong(v);
164     }
165 
166     public final void writeShort(int v) throws IOException {
167         out.writeShort(v);
168     }
169 
170     public final void writeUTF(String str) throws IOException {
171         out.writeUTF(str);
172     }
173 }