java中字符窜与16进制，byte之间的转换

/**

* java String 与各种进制字符之间的转换

* 

* @author

*/

 publicclass 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 

     */

    publicstatic String bin2hex(String bin) {

        char[] digital ="0123456789ABCDEF".toCharArray();

        StringBuffer sb =new StringBuffer("");

        byte[] bs = bin.getBytes();

        intbit;

        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]);

        }

        returnsb.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

     */

    publicstatic String hex2bin(String hex) {

        String digital ="0123456789ABCDEF";

        char[] hex2char = hex.toCharArray();

        byte[] bytes =new byte[hex.length() /2];

        inttemp;

        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);

        }

        returnnew String(bytes);

    }

  

    /** 

     * java字节码转字符串 

     * @param b 

     * @return 

     */

    publicstatic 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;

        returnhs.toUpperCase(); //转成大写

    }

  

    /**

     * 字符串转java字节码

     * @param b

     * @return

     */

    publicstatic byte[] hex2byte(byte[] b) {

        if((b.length % 2) !=0) {

            thrownew 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;

        returnb2;

    }

  

    publicstatic void main(String[] args) {

        String content ="EDF%&^%#_|~";

        System.out.println(bin2hex(content));

        System.out.println(hex2bin(bin2hex(content)));

    }

}