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1
57
58 package com.sun.org.apache.xerces.internal.impl.dv.util;
59
60
67 public final class HexBin {
68 static private final int BASELENGTH = 255;
69 static private final int LOOKUPLENGTH = 16;
70 static final private byte [] hexNumberTable = new byte[BASELENGTH];
71 static final private char [] lookUpHexAlphabet = new char[LOOKUPLENGTH];
72
73
74 static {
75 for (int i = 0; i<BASELENGTH; i++ ) {
76 hexNumberTable[i] = -1;
77 }
78 for ( int i = '9'; i >= '0'; i--) {
79 hexNumberTable[i] = (byte) (i-'0');
80 }
81 for ( int i = 'F'; i>= 'A'; i--) {
82 hexNumberTable[i] = (byte) ( i-'A' + 10 );
83 }
84 for ( int i = 'f'; i>= 'a'; i--) {
85 hexNumberTable[i] = (byte) ( i-'a' + 10 );
86 }
87
88 for(int i = 0; i<10; i++ )
89 lookUpHexAlphabet[i] = (char)('0'+i);
90 for(int i = 10; i<=15; i++ )
91 lookUpHexAlphabet[i] = (char)('A'+i -10);
92 }
93
94
100 static public String  encode(byte[] binaryData) {
101 if (binaryData == null)
102 return null;
103 int lengthData = binaryData.length;
104 int lengthEncode = lengthData * 2;
105 char[] encodedData = new char[lengthEncode];
106 int temp;
107 for (int i = 0; i < lengthData; i++) {
108 temp = binaryData[i];
109 if (temp < 0)
110 temp += 256;
111 encodedData[i*2] = lookUpHexAlphabet[temp >> 4];
112 encodedData[i*2+1] = lookUpHexAlphabet[temp & 0xf];
113 }
114 return new String (encodedData);
115 }
116
117
123 static public byte[] decode(String encoded) {
124 if (encoded == null)
125 return null;
126 int lengthData = encoded.length();
127 if (lengthData % 2 != 0)
128 return null;
129
130 char[] binaryData = encoded.toCharArray();
131 int lengthDecode = lengthData / 2;
132 byte[] decodedData = new byte[lengthDecode];
133 byte temp1, temp2;
134 for( int i = 0; i<lengthDecode; i++ ){
135 temp1 = hexNumberTable[binaryData[i*2]];
136 if (temp1 == -1)
137 return null;
138 temp2 = hexNumberTable[binaryData[i*2+1]];
139 if (temp2 == -1)
140 return null;
141 decodedData[i] = (byte)((temp1 << 4) | temp2);
142 }
143 return decodedData;
144 }
145 }
146 |
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