java

package org.lib.code;  
  
/** 
 * java String 与各种进制字符之间的转换 
 *  
 * @author 流水孟春^篱笆墙外 08.3.4 
 */  
public class Coding {  
  
    /** 
     * 字符串转换成十六进制值 
     * @param bin String 我们看到的要转换成十六进制的字符串 
     * @return  
     */  
    public static String bin2hex(String bin) {  
        char[] digital = "0123456789ABCDEF".toCharArray();  
        StringBuffer sb = new StringBuffer("");  
        byte[] bs = bin.getBytes();  
        int bit;  
        for (int i = 0; i < bs.length; i++) {  
            bit = (bs[i] & 0x0f0) >> 4;  
            sb.append(digital[bit]);  
            bit = bs[i] & 0x0f;  
            sb.append(digital[bit]);  
        }  
        return sb.toString();  
    }  
  
    /** 
     * 十六进制转换字符串 
     * @param hex String 十六进制 
     * @return String 转换后的字符串 
     */  
    public static String hex2bin(String hex) {  
        String digital = "0123456789ABCDEF";  
        char[] hex2char = hex.toCharArray();  
        byte[] bytes = new byte[hex.length() / 2];  
        int temp;  
        for (int i = 0; i < bytes.length; i++) {  
            temp = digital.indexOf(hex2char[2 * i]) * 16;  
            temp += digital.indexOf(hex2char[2 * i + 1]);  
            bytes[i] = (byte) (temp & 0xff);  
        }  
        return new String(bytes);  
    }  
  
    /**  
     * java字节码转字符串  
     * @param b  
     * @return  
     */  
    public static String byte2hex(byte[] b) { //一个字节的数，  
  
        // 转成16进制字符串  
  
        String hs = "";  
        String tmp = "";  
        for (int n = 0; n < b.length; n++) {  
            //整数转成十六进制表示  
  
            tmp = (java.lang.Integer.toHexString(b[n] & 0XFF));  
            if (tmp.length() == 1) {  
                hs = hs + "0" + tmp;  
            } else {  
                hs = hs + tmp;  
            }  
        }  
        tmp = null;  
        return hs.toUpperCase(); //转成大写  
  
    }  
  
    /** 
     * 字符串转java字节码 
     * @param b 
     * @return 
     */  
    public static byte[] hex2byte(byte[] b) {  
        if ((b.length % 2) != 0) {  
            throw new IllegalArgumentException("长度不是偶数");  
        }  
        byte[] b2 = new byte[b.length / 2];  
        for (int n = 0; n < b.length; n += 2) {  
            String item = new String(b, n, 2);  
            // 两位一组，表示一个字节,把这样表示的16进制字符串，还原成一个进制字节  
  
            b2[n / 2] = (byte) Integer.parseInt(item, 16);  
        }  
        b = null;  
        return b2;  
    }  
  
    public static void main(String[] args) {  
        String content = "技术性问题EDF%&^%#_|~";  
        System.out.println(bin2hex(content));  
        System.out.println(hex2bin(bin2hex(content)));  
    }  
}   

转自:http://classdemo.iteye.com/blog/246073