001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 */ 019package org.apache.directory.api.util; 020 021 022/** 023 * A class containing static methods used to serialize and deserialize base types 024 * 025 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 026 */ 027public final class Serialize 028{ 029 /** The serialized value for TRUE */ 030 public static final byte TRUE = 0x01; 031 032 /** The serialized value for FALSE */ 033 public static final byte FALSE = 0x00; 034 035 036 private Serialize() 037 { 038 } 039 040 041 /** 042 * Write an integer into a buffer at a given position 043 * 044 * @param value The value to serialize 045 * @param buffer The buffer to store the value into 046 * @param pos The position where we serialize the integer 047 * @return The new position in the byte[] 048 */ 049 public static int serialize( int value, byte[] buffer, int pos ) 050 { 051 if ( buffer.length - pos < 4 ) 052 { 053 throw new ArrayIndexOutOfBoundsException(); 054 } 055 056 buffer[pos++] = ( byte ) ( ( value >>> 24 ) & 0xFF ); 057 buffer[pos++] = ( byte ) ( ( value >>> 16 ) & 0xFF ); 058 buffer[pos++] = ( byte ) ( ( value >>> 8 ) & 0xFF ); 059 buffer[pos++] = ( byte ) ( ( value >>> 0 ) & 0xFF ); 060 061 return pos; 062 } 063 064 065 /** 066 * Write a byte[] into a buffer at a given position 067 * 068 * @param value The value to serialize 069 * @param buffer The buffer to store the value into 070 * @param pos The position where we serialize the byte[] 071 * @return The new position in the byte[] 072 */ 073 public static int serialize( byte[] value, byte[] buffer, int pos ) 074 { 075 if ( buffer.length - pos < 4 + value.length ) 076 { 077 throw new ArrayIndexOutOfBoundsException(); 078 } 079 080 buffer[pos++] = ( byte ) ( ( value.length >>> 24 ) & 0xFF ); 081 buffer[pos++] = ( byte ) ( ( value.length >>> 16 ) & 0xFF ); 082 buffer[pos++] = ( byte ) ( ( value.length >>> 8 ) & 0xFF ); 083 buffer[pos++] = ( byte ) ( ( value.length >>> 0 ) & 0xFF ); 084 085 System.arraycopy( value, 0, buffer, pos, value.length ); 086 087 return pos + value.length; 088 } 089 090 091 /** 092 * Read an integer from a buffer at a given position 093 * 094 * @param buffer The buffer containing the serialized integer 095 * @param pos The position from which we will read an integer 096 * @return the deserialized integer 097 */ 098 public static int deserializeInt( byte[] buffer, int pos ) 099 { 100 if ( buffer.length - pos < 4 ) 101 { 102 throw new ArrayIndexOutOfBoundsException(); 103 } 104 105 return ( buffer[pos] << 24 ) + ( buffer[pos + 1] << 16 ) + ( buffer[pos + 2] << 8 ) + ( buffer[pos + 3] << 0 ); 106 } 107 108 109 /** 110 * Read a byte[] from a buffer at a given position 111 * 112 * @param buffer The buffer containing the serialized byte[] 113 * @param pos The position from which we will read a byte[] 114 * @return the deserialized byte[] 115 */ 116 public static byte[] deserializeBytes( byte[] buffer, int pos ) 117 { 118 if ( buffer.length - pos < 4 ) 119 { 120 throw new ArrayIndexOutOfBoundsException(); 121 } 122 123 int len = deserializeInt( buffer, pos ); 124 pos += 4; 125 126 if ( len > 0 ) 127 { 128 if ( buffer.length - pos < len ) 129 { 130 throw new ArrayIndexOutOfBoundsException(); 131 } 132 133 byte[] result = new byte[len]; 134 135 System.arraycopy( buffer, pos, result, 0, len ); 136 137 return result; 138 } 139 else 140 { 141 return Strings.EMPTY_BYTES; 142 } 143 } 144 145 146 /** 147 * Read a boolean from a buffer at a given position 148 * 149 * @param buffer The buffer containing the serialized boolean 150 * @param pos The position from which we will read a boolean 151 * @return the deserialized boolean 152 */ 153 public static boolean deserializeBoolean( byte[] buffer, int pos ) 154 { 155 if ( buffer.length - pos < 1 ) 156 { 157 throw new ArrayIndexOutOfBoundsException(); 158 } 159 160 byte value = buffer[pos]; 161 162 return ( value != 0x00 ); 163 } 164}