Java实现的utf8，gbk，unicode编码相互转换的代码详解编程语言

Java实现的utf8，gbk，unicode编码相互转换的代码

public class UTF2GBK { 
      
    public String gbk2utf8(String gbk) { 
        String l_temp = GBK2Unicode(gbk); 
        l_temp = unicodeToUtf8(l_temp); 
  
        return l_temp; 
    } 
  
    public String utf82gbk(String utf) { 
        String l_temp = utf8ToUnicode(utf); 
        l_temp = Unicode2GBK(l_temp); 
  
        return l_temp; 
    } 
  
    /** 
     * 
     * @param str 
     * @return String 
     */ 
  
    public static String GBK2Unicode(String str) { 
        StringBuffer result = new StringBuffer(); 
        for (int i = 0; i < str.length(); i++) { 
            char chr1 = (char) str.charAt(i); 
  
            if (!isNeedConvert(chr1)) { 
                result.append(chr1); 
                continue; 
            } 
  
            result.append("//u" + Integer.toHexString((int) chr1)); 
        } 
  
        return result.toString(); 
    } 
  
    /** 
     * 
     * @param dataStr 
     * @return String 
     */ 
  
    public static String Unicode2GBK(String dataStr) { 
        int index = 0; 
        StringBuffer buffer = new StringBuffer(); 
  
        int li_len = dataStr.length(); 
        while (index < li_len) { 
            if (index >= li_len - 1 
                    || !"//u".equals(dataStr.substring(index, index + 2))) { 
                buffer.append(dataStr.charAt(index)); 
  
                index++; 
                continue; 
            } 
  
            String charStr = ""; 
            charStr = dataStr.substring(index + 2, index + 6); 
  
            char letter = (char) Integer.parseInt(charStr, 16); 
  
            buffer.append(letter); 
            index += 6; 
        } 
  
        return buffer.toString(); 
    } 
  
    public static boolean isNeedConvert(char para) { 
        return ((para & (0x00FF)) != para); 
    } 
  
    /** 
     * utf-8 转unicode 
     * 
     * @param inStr 
     * @return String 
     */ 
    public static String utf8ToUnicode(String inStr) { 
        char[] myBuffer = inStr.toCharArray(); 
  
        StringBuffer sb = new StringBuffer(); 
        for (int i = 0; i < inStr.length(); i++) { 
            UnicodeBlock ub = UnicodeBlock.of(myBuffer[i]); 
            if (ub == UnicodeBlock.BASIC_LATIN) { 
                sb.append(myBuffer[i]); 
            } else if (ub == UnicodeBlock.HALFWIDTH_AND_FULLWIDTH_FORMS) { 
                int j = (int) myBuffer[i] - 65248; 
                sb.append((char) j); 
            } else { 
                short s = (short) myBuffer[i]; 
                String hexS = Integer.toHexString(s); 
                String unicode = "//u" + hexS; 
                sb.append(unicode.toLowerCase()); 
            } 
        } 
        return sb.toString(); 
    } 
  
    /** 
     * 
     * @param theString 
     * @return String 
     */ 
    public static String unicodeToUtf8(String theString) { 
        char aChar; 
        int len = theString.length(); 
        StringBuffer outBuffer = new StringBuffer(len); 
        for (int x = 0; x < len;) { 
            aChar = theString.charAt(x++); 
            if (aChar == '//') { 
                aChar = theString.charAt(x++); 
                if (aChar == 'u') { 
                    // Read the xxxx 
                    int value = 0; 
                    for (int i = 0; i < 4; i++) { 
                        aChar = theString.charAt(x++); 
                        switch (aChar) { 
                        case '0': 
                        case '1': 
                        case '2': 
                        case '3': 
                        case '4': 
                        case '5': 
                        case '6': 
                        case '7': 
                        case '8': 
                        case '9': 
                            value = (value << 4) + aChar - '0'; 
                            break; 
                        case 'a': 
                        case 'b': 
                        case 'c': 
                        case 'd': 
                        case 'e': 
                        case 'f': 
                            value = (value << 4) + 10 + aChar - 'a'; 
                            break; 
                        case 'A': 
                        case 'B': 
                        case 'C': 
                        case 'D': 
                        case 'E': 
                        case 'F': 
                            value = (value << 4) + 10 + aChar - 'A'; 
                            break; 
                        default: 
                            throw new IllegalArgumentException( 
                                    "Malformed   //uxxxx   encoding."); 
                        } 
                    } 
                    outBuffer.append((char) value); 
                } else { 
                    if (aChar == 't') 
                        aChar = '/t'; 
                    else if (aChar == 'r') 
                        aChar = '/r'; 
                    else if (aChar == 'n') 
                        aChar = '/n'; 
                    else if (aChar == 'f') 
                        aChar = '/f'; 
                    outBuffer.append(aChar); 
                } 
            } else 
                outBuffer.append(aChar); 
        } 
        return outBuffer.toString(); 
    } 
  
}