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57
58 package org.enhydra.apache.xerces.utils;
59
60
61
62
69
70 public final class HexBin {
71 static private final int BASELENGTH = 255;
72 static private final int LOOKUPLENGTH = 16;
73 static private byte [] hexNumberTable = new byte[BASELENGTH];
74 static private byte [] lookUpHexAlphabet = new byte[LOOKUPLENGTH];
75
76
77 static {
78 for (int i = 0; i<BASELENGTH; i++ ) {
79 hexNumberTable[i] = -1;
80 }
81 for ( int i = '9'; i >= '0'; i--) {
82 hexNumberTable[i] = (byte) (i-'0');
83 }
84 for ( int i = 'F'; i>= 'A'; i--) {
85 hexNumberTable[i] = (byte) ( i-'A' + 10 );
86 }
87 for ( int i = 'f'; i>= 'a'; i--) {
88 hexNumberTable[i] = (byte) ( i-'a' + 10 );
89 }
90
91 for(int i = 0; i<10; i++ )
92 lookUpHexAlphabet[i] = (byte) ('0'+i );
93 for(int i = 10; i<=15; i++ )
94 lookUpHexAlphabet[i] = (byte) ('A'+i -10);
95 }
96
97
103 static boolean isHex( byte octect ) {
104 return( hexNumberTable[octect] != -1 );
106 }
107
108
109
115 static boolean isArrayByteHex( byte[] arrayOctect ) {
116 if (arrayOctect == null)
117 return false;
118 int length = arrayOctect.length;
119 if (length % 2 != 0)
120 return false;
121 for( int i=0; i < length; i++ ){
122 if( HexBin.isHex( arrayOctect[i] ) == false)
123 return false;
124 }
125 return true;
126 }
127
128 public static boolean isHex( String  isValidString ){
129 if (isValidString == null)
130 return false;
131 return( isArrayByteHex( isValidString.getBytes()));
132 }
133
134
140 static public byte[] encode( byte[] binaryData ) {
141 if (binaryData == null)
142 return null;
143 int lengthData = binaryData.length;
144 int lengthEncode = lengthData * 2;
145 byte[] encodedData = new byte[lengthEncode];
146 for( int i = 0; i<lengthData; i++ ){
147 encodedData[i*2] = lookUpHexAlphabet[ binaryData[i] >> 4];
148 encodedData[i*2+1] = lookUpHexAlphabet[ binaryData[i] & 0xf];
149 }
150 return encodedData;
151 }
152
153 static public byte[] decode ( byte[] binaryData ) {
154 if (binaryData == null)
155 return null;
156 int lengthData = binaryData.length;
157 if (lengthData % 2 != 0)
158 return null;
159
160 int lengthDecode = lengthData / 2;
161 byte[] decodedData = new byte[lengthDecode];
162 for( int i = 0; i<lengthDecode; i++ ){
163 decodedData[i] = (byte)((hexNumberTable[binaryData[i*2]] << 4) | hexNumberTable[binaryData[i*2+1]]);
164 }
165 return decodedData;
166 }
167
168 static public int getDecodedDataLength (byte[] hexData) {
169 if (!isArrayByteHex(hexData))
170 return -1;
171
172 return hexData.length / 2;
173 }
174 }
175 |
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