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 package org.apache.directory.api.util;
20
21
22 /**
23 * A class containing static methods used to serialize and deserialize base types
24 *
25 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
26 */
27 public class Serialize
28 {
29 public final static byte TRUE = 0x01;
30 public final static byte FALSE = 0x00;
31
32
33 /**
34 * Write an integer into a buffer at a given position
35 *
36 * @param value The value to serialize
37 * @param buffer The buffer to store the value into
38 * @param pos The position where we serialize the integer
39 */
40 public static int serialize( int value, byte[] buffer, int pos )
41 {
42 if ( buffer.length - pos < 4 )
43 {
44 throw new ArrayIndexOutOfBoundsException();
45 }
46
47 buffer[pos++] = ( byte ) ( ( value >>> 24 ) & 0xFF );
48 buffer[pos++] = ( byte ) ( ( value >>> 16 ) & 0xFF );
49 buffer[pos++] = ( byte ) ( ( value >>> 8 ) & 0xFF );
50 buffer[pos++] = ( byte ) ( ( value >>> 0 ) & 0xFF );
51
52 return pos;
53 }
54
55
56 /**
57 * Write a byte[] into a buffer at a given position
58 *
59 * @param value The value to serialize
60 * @param buffer The buffer to store the value into
61 * @param pos The position where we serialize the byte[]
62 */
63 public static int serialize( byte[] value, byte[] buffer, int pos )
64 {
65 if ( buffer.length - pos < 4 + value.length )
66 {
67 throw new ArrayIndexOutOfBoundsException();
68 }
69
70 buffer[pos++] = ( byte ) ( ( value.length >>> 24 ) & 0xFF );
71 buffer[pos++] = ( byte ) ( ( value.length >>> 16 ) & 0xFF );
72 buffer[pos++] = ( byte ) ( ( value.length >>> 8 ) & 0xFF );
73 buffer[pos++] = ( byte ) ( ( value.length >>> 0 ) & 0xFF );
74
75 System.arraycopy( value, 0, buffer, pos, value.length );
76
77 return pos + value.length;
78 }
79
80
81 /**
82 * Read an integer from a buffer at a given position
83 *
84 * @param buffer The buffer containing the serialized integer
85 * @param pos The position from which we will read an integer
86 * @return the deserialized integer
87 */
88 public static int deserializeInt( byte[] buffer, int pos )
89 {
90 if ( buffer.length - pos < 4 )
91 {
92 throw new ArrayIndexOutOfBoundsException();
93 }
94
95 return ( buffer[pos] << 24 ) + ( buffer[pos + 1] << 16 ) + ( buffer[pos + 2] << 8 ) + ( buffer[pos + 3] << 0 );
96 }
97
98
99 /**
100 * Read a byte[] from a buffer at a given position
101 *
102 * @param buffer The buffer containing the serialized byte[]
103 * @param pos The position from which we will read a byte[]
104 * @return the deserialized byte[]
105 */
106 public static byte[] deserializeBytes( byte[] buffer, int pos )
107 {
108 if ( buffer.length - pos < 4 )
109 {
110 throw new ArrayIndexOutOfBoundsException();
111 }
112
113 int len = deserializeInt( buffer, pos );
114 pos += 4;
115
116 if ( len > 0 )
117 {
118 if ( buffer.length - pos < len )
119 {
120 throw new ArrayIndexOutOfBoundsException();
121 }
122
123 byte[] result = new byte[len];
124
125 System.arraycopy( buffer, pos, result, 0, len );
126
127 return result;
128 }
129 else
130 {
131 return Strings.EMPTY_BYTES;
132 }
133 }
134
135
136 /**
137 * Read a boolean from a buffer at a given position
138 *
139 * @param buffer The buffer containing the serialized boolean
140 * @param pos The position from which we will read a boolean
141 * @return the deserialized boolean
142 */
143 public static boolean deserializeBoolean( byte[] buffer, int pos )
144 {
145 if ( buffer.length - pos < 1 )
146 {
147 throw new ArrayIndexOutOfBoundsException();
148 }
149
150 byte value = buffer[pos];
151
152 return ( value != 0x00 );
153 }
154 }