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.directory.mavibot.btree.serializer;
21
22
23 import java.io.IOException;
24 import java.nio.ByteBuffer;
25
26 import org.apache.directory.mavibot.btree.comparator.IntComparator;
27
28
29 /**
30 * The Integer serializer.
31 *
32 * @author <a href="mailto:labs@labs.apache.org">Mavibot labs Project</a>
33 */
34 public class IntSerializer extends AbstractElementSerializer<Integer>
35 {
36 /**
37 * Create a new instance of IntSerializer
38 */
39 public IntSerializer()
40 {
41 super( new IntComparator() );
42 }
43
44
45 /**
46 * A static method used to deserialize an Integer from a byte array.
47 * @param in The byte array containing the Integer
48 * @return An Integer
49 */
50 public static Integer deserialize( byte[] in )
51 {
52 return deserialize( in, 0 );
53 }
54
55
56 /**
57 * A static method used to deserialize an Integer from a byte array.
58 * @param in The byte array containing the Integer
59 * @param start the position in the byte[] we will deserialize the int from
60 * @return An Integer
61 */
62 public static Integer deserialize( byte[] in, int start )
63 {
64 if ( ( in == null ) || ( in.length < 4 + start ) )
65 {
66 throw new RuntimeException( "Cannot extract a Integer from a buffer with not enough bytes" );
67 }
68
69 return ( in[start] << 24 ) +
70 ( ( in[start + 1] & 0xFF ) << 16 ) +
71 ( ( in[start + 2] & 0xFF ) << 8 ) +
72 ( in[start + 3] & 0xFF );
73 }
74
75
76 /**
77 * {@inheritDoc}
78 */
79 public Integer deserialize( ByteBuffer buffer ) throws IOException
80 {
81 return buffer.getInt();
82 }
83
84
85 /**
86 * {@inheritDoc}
87 */
88 public Integer deserialize( BufferHandler bufferHandler ) throws IOException
89 {
90 byte[] in = bufferHandler.read( 4 );
91
92 return deserialize( in );
93 }
94
95
96 /**
97 * {@inheritDoc}
98 */
99 public byte[] serialize( Integer element )
100 {
101 return serialize( element.intValue() );
102 }
103
104
105 /**
106 * Serialize an int
107 *
108 * @param value the value to serialize
109 * @return The byte[] containing the serialized int
110 */
111 public static byte[] serialize( int value )
112 {
113 byte[] bytes = new byte[4];
114
115 return serialize( bytes, 0, value );
116 }
117
118
119 /**
120 * Serialize an int
121 *
122 * @param buffer the Buffer that will contain the serialized value
123 * @param start the position in the buffer we will store the serialized int
124 * @param value the value to serialize
125 * @return The byte[] containing the serialized int
126 */
127 public static byte[] serialize( byte[] buffer, int start, int value )
128 {
129 buffer[start] = ( byte ) ( value >>> 24 );
130 buffer[start + 1] = ( byte ) ( value >>> 16 );
131 buffer[start + 2] = ( byte ) ( value >>> 8 );
132 buffer[start + 3] = ( byte ) ( value );
133
134 return buffer;
135 }
136 }