Java 编程下字符串的 16 位、32位 MD5 加密

package cn.sunzn.md5;

import java.security.MessageDigest;

import java.security.NoSuchAlgorithmException;

public class Str2MD5 {

public static void main(String[] args) {

MD5("sunzn");

}

private static String MD5(String sourceStr) {

String result = "";

try {

MessageDigest md = MessageDigest.getInstance("MD5");

md.update(sourceStr.getBytes());

byte b[] = md.digest();

int i;

StringBuffer buf = new StringBuffer("");

for (int offset = 0; offset < b.length; offset++) {

i = b[offset];

if (i < 0)

i += 256;

if (i < 16)

buf.append("0");

buf.append(Integer.toHexString(i));

}

result = buf.toString();

System.out.println("MD5(" + sourceStr + ",32) = " + result);

System.out.println("MD5(" + sourceStr + ",16) = " + buf.toString().substring(8, 24));

} catch (NoSuchAlgorithmException e) {

System.out.println(e);

}

return result;

}

}