#urlencoder

使用：

URLencoder.encode(str, "GB2312");//GB2312编码

URLencoder.encode(str, "UTF-8");//UTF-8编码

源代码：

import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.OutputStreamWriter; import java.io.UnsupportedEncodingException; /**  * Adapted from J2SE java.net.URLEncoder.  */ public class URLGB2312encoder {         public static String encode(String s, String enc)     throws UnsupportedEncodingException {     boolean needToChange = false;     boolean wroteUnencodedChar = false;     int maxBytesPerChar = 10; // rather arbitrary limit, but safe for now       StringBuffer out = new StringBuffer(s.length());     ByteArrayOutputStream buf = new ByteArrayOutputStream(maxBytesPerChar);     OutputStreamWriter writer = new OutputStreamWriter(buf, enc);     for (int i = 0; i < s.length(); i++) {         int c = (int) s.charAt(i);         if (dontNeedEncoding(c)) {         if (c == ' ') {             c = '+';             needToChange = true;         }         out.append((char)c);         wroteUnencodedChar = true;         } else {         // convert to external encoding before hex conversion         try {             if (wroteUnencodedChar) { // Fix for 4407610                 writer = new OutputStreamWriter(buf, enc);             wroteUnencodedChar = false;             }             writer.write(c);             /*              * If this character represents the start of a Unicode              * surrogate pair, then pass in two characters. It's not              * clear what should be done if a bytes reserved in the              * surrogate pairs range occurs outside of a legal              * surrogate pair. For now, just treat it as if it were              * any other character.              */             if (c >= 0xD800 && c <= 0xDBFF) {             /*               System.out.println(Integer.toHexString(c)               + " is high surrogate");             */             if ( (i+1) < s.length()) {                 int d = (int) s.charAt(i+1);                 /*                   System.out.println("\tExamining "                   + Integer.toHexString(d));                 */                 if (d >= 0xDC00 && d <= 0xDFFF) {                 /*                   System.out.println("\t"                   + Integer.toHexString(d)                   + " is low surrogate");                 */                 writer.write(d);                 i++;                 }             }             }             writer.flush();         } catch(IOException e) {             buf.reset();             continue;         }         byte[] ba = buf.toByteArray();         for (int j = 0; j < ba.length; j++) {             out.append('%');             char ch = CCharacter.forDigit((ba[j] >> 4) & 0xF, 16);             out.append(ch);             ch = CCharacter.forDigit(ba[j] & 0xF, 16);             out.append(ch);         }         buf.reset();         needToChange = true;         }     }     return (needToChange? out.toString() : s);   }    static class CCharacter {     public static char forDigit(int digit, int radix) {       if ((digit >= radix) || (digit < 0)) {           return '\0';       }       if ((radix < Character.MIN_RADIX) || (radix > Character.MAX_RADIX)) {           return '\0';       }       if (digit < 10) {           return (char)('0' + digit);       }       return (char)('A' - 10 + digit);   }   }   public static boolean dontNeedEncoding(int ch){     int len = _dontNeedEncoding.length();     boolean en = false;     for(int i =0;i< len;i++){       if(_dontNeedEncoding.charAt(i) == ch)       {         en = true;         break;       }     }         return en;   }   //private static final int caseDiff = ('a' - 'A');   private static String _dontNeedEncoding = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ -_.*"; }