app开发历程————服务器端生成JSON格式数据，采用Unicode编码，隐藏中文

  1 package mobi.chenwei.wing.util;
  2 
  3 public class CharacterSetToolkit {
  4 
  5     /**
  6      * @param args
  7      */
  8     public static void main(String[] args) {
  9         // TODO Auto-generated method stub
 10         String s = "天津";
 11         System.out.println("Original:\t\t" + s);  
 12         
 13           s = toEncodedUnicode(s, true);  
 14             System.out.println("to unicode:\t\t" + s);  
 15             
 16             
 17             s = fromEncodedUnicode(s.toCharArray(), 0, s.length());  
 18             System.out.println("from unicode:\t" + s);  
 19         
 20 
 21     }
 22     private static final char[] hexDigit = { ‘0‘, ‘1‘, ‘2‘, ‘3‘, ‘4‘, ‘5‘, ‘6‘, ‘7‘, ‘8‘, ‘9‘, ‘A‘,  
 23         ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘ };  
 24 
 25 private static char toHex(int nibble) {  
 26     return hexDigit[(nibble & 0xF)];  
 27 }  
 28 /** 
 29  * 将字符串编码成 Unicode 形式的字符串. 如 "黄" to "\u9EC4" 
 30  * Converts unicodes to encoded \\uxxxx and escapes 
 31  * special characters with a preceding slash 
 32  *  
 33  * @param theString 
 34  *        待转换成Unicode编码的字符串。 
 35  * @param escapeSpace 
 36  *        是否忽略空格，为true时在空格后面是否加个反斜杠。 
 37  * @return 返回转换后Unicode编码的字符串。 
 38  */  
 39 public static String toEncodedUnicode(String theString, boolean escapeSpace) {  
 40     int len = theString.length();  
 41     int bufLen = len * 2;  
 42     if (bufLen < 0) {  
 43         bufLen = Integer.MAX_VALUE;  
 44     }  
 45     StringBuffer outBuffer = new StringBuffer(bufLen);  
 46 
 47     for (int x = 0; x < len; x++) {  
 48         char aChar = theString.charAt(x);  
 49         // Handle common case first, selecting largest block that  
 50         // avoids the specials below  
 51         if ((aChar > 61) && (aChar < 127)) {  
 52             if (aChar == ‘\\‘) {  
 53                 outBuffer.append(‘\\‘);  
 54                 outBuffer.append(‘\\‘);  
 55                 continue;  
 56             }  
 57             outBuffer.append(aChar);  
 58             continue;  
 59         }  
 60           
 61         switch (aChar) {  
 62         case ‘ ‘:  
 63             if (x == 0 || escapeSpace) outBuffer.append(‘\\‘);  
 64             outBuffer.append(‘ ‘);  
 65             break;  
 66         case ‘\t‘:  
 67             outBuffer.append(‘\\‘);  
 68             outBuffer.append(‘t‘);  
 69             break;  
 70         case ‘\n‘:  
 71             outBuffer.append(‘\\‘);  
 72             outBuffer.append(‘n‘);  
 73             break;  
 74         case ‘\r‘:  
 75             outBuffer.append(‘\\‘);  
 76             outBuffer.append(‘r‘);  
 77             break;  
 78         case ‘\f‘:  
 79             outBuffer.append(‘\\‘);  
 80             outBuffer.append(‘f‘);  
 81             break;  
 82         case ‘=‘: // Fall through  
 83         case ‘:‘: // Fall through  
 84         case ‘#‘: // Fall through  
 85         case ‘!‘:  
 86             outBuffer.append(‘\\‘);  
 87             outBuffer.append(aChar);  
 88             break;  
 89         default:  
 90             if ((aChar < 0x0020) || (aChar > 0x007e)) {  
 91                 // 每个unicode有16位，每四位对应的16进制从高位保存到低位  
 92                 outBuffer.append(‘\\‘);  
 93                 outBuffer.append(‘u‘);  
 94                 outBuffer.append(toHex((aChar >> 12) & 0xF));  
 95                 outBuffer.append(toHex((aChar >> 8) & 0xF));  
 96                 outBuffer.append(toHex((aChar >> 4) & 0xF));  
 97                 outBuffer.append(toHex(aChar & 0xF));  
 98             } else {  
 99                 outBuffer.append(aChar);  
100             }  
101         }  
102     }  
103     return outBuffer.toString();  
104 }  
105 
106 /** 
107  * 从 Unicode 形式的字符串转换成对应的编码的特殊字符串。 如 "\u9EC4" to "黄". 
108  * Converts encoded \\uxxxx to unicode chars 
109  * and changes special saved chars to their original forms 
110  *  
111  * @param in 
112  *        Unicode编码的字符数组。 
113  * @param off 
114  *        转换的起始偏移量。 
115  * @param len 
116  *        转换的字符长度。 
117  * @param convtBuf 
118  *        转换的缓存字符数组。 
119  * @return 完成转换，返回编码前的特殊字符串。 
120  */  
121 public static String fromEncodedUnicode(char[] in, int off, int len) {  
122     char aChar;  
123     char[] out = new char[len]; // 只短不长  
124     int outLen = 0;  
125     int end = off + len;  
126 
127     while (off < end) {  
128         aChar = in[off++];  
129         if (aChar == ‘\\‘) {  
130             aChar = in[off++];  
131             if (aChar == ‘u‘) {  
132                 // Read the xxxx  
133                 int value = 0;  
134                 for (int i = 0; i < 4; i++) {  
135                     aChar = in[off++];  
136                     switch (aChar) {  
137                     case ‘0‘:  
138                     case ‘1‘:  
139                     case ‘2‘:  
140                     case ‘3‘:  
141                     case ‘4‘:  
142                     case ‘5‘:  
143                     case ‘6‘:  
144                     case ‘7‘:  
145                     case ‘8‘:  
146                     case ‘9‘:  
147                         value = (value << 4) + aChar - ‘0‘;  
148                         break;  
149                     case ‘a‘:  
150                     case ‘b‘:  
151                     case ‘c‘:  
152                     case ‘d‘:  
153                     case ‘e‘:  
154                     case ‘f‘:  
155                         value = (value << 4) + 10 + aChar - ‘a‘;  
156                         break;  
157                     case ‘A‘:  
158                     case ‘B‘:  
159                     case ‘C‘:  
160                     case ‘D‘:  
161                     case ‘E‘:  
162                     case ‘F‘:  
163                         value = (value << 4) + 10 + aChar - ‘A‘;  
164                         break;  
165                     default:  
166                         throw new IllegalArgumentException("Malformed \\uxxxx encoding.");  
167                     }  
168                 }  
169                 out[outLen++] = (char) value;  
170             } else {  
171                 if (aChar == ‘t‘) {  
172                     aChar = ‘\t‘;  
173                 } else if (aChar == ‘r‘) {  
174                     aChar = ‘\r‘;  
175                 } else if (aChar == ‘n‘) {  
176                     aChar = ‘\n‘;  
177                 } else if (aChar == ‘f‘) {  
178                     aChar = ‘\f‘;  
179                 }  
180                 out[outLen++] = aChar;  
181             }  
182         } else {  
183             out[outLen++] = (char) aChar;  
184         }  
185     }  
186     return new String(out, 0, outLen);  
187 } 
188 }