java md5加密

package com.h3c.imc.sgyy.sms;


import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;


import sun.misc.BASE64Encoder;


/**
 * MD5 encrypt algorithm. <br>
 * Encryption irreversible.
 *
 */
public final class MD5 {


/** Determine encrypt algorithm MD5 */
private static final String ALGORITHM_MD5 = "MD5";
/** UTF-8 Encoding */
private static final String UTF_8 = "UTF-8";


/**
* MD5 16bit Encrypt Methods.
* 
* @param readyEncryptStr
*            ready encrypt string
* @return String encrypt result string
* @throws NoSuchAlgorithmException
*/
public static final String MD5_16bit(String readyEncryptStr) throws NoSuchAlgorithmException {
if (readyEncryptStr != null) {
return MD5.MD5_32bit(readyEncryptStr).substring(8, 24);
} else {
return null;
}
}


/**
* MD5 32bit Encrypt Methods.
* 
* @param readyEncryptStr
*            ready encrypt string
* @return String encrypt result string
* @throws NoSuchAlgorithmException
*/
public static final String MD5_32bit(String readyEncryptStr) throws NoSuchAlgorithmException {
if (readyEncryptStr != null) {
// Get MD5 digest algorithm's MessageDigest's instance.
MessageDigest md = MessageDigest.getInstance(ALGORITHM_MD5);
// Use specified byte update digest.
md.update(readyEncryptStr.getBytes());
// Get cipher text
byte[] b = md.digest();
// The cipher text converted to hexadecimal string
StringBuilder su = new StringBuilder();
// byte array switch hexadecimal number.
for (int offset = 0, bLen = b.length; offset < bLen; offset++) {
String haxHex = Integer.toHexString(b[offset] & 0xFF);
if (haxHex.length() < 2) {
su.append("0");
}
su.append(haxHex);
}
return su.toString();
} else {
return null;
}
}


/**
* MD5 32bit Encrypt Methods.
* 
* @param readyEncryptStr
*            ready encrypt string
* @return String encrypt result string
* @throws NoSuchAlgorithmException
*/
public static final String MD5_32bit1(String readyEncryptStr) throws NoSuchAlgorithmException {
if (readyEncryptStr != null) {
// The cipher text converted to hexadecimal string
StringBuilder su = new StringBuilder();
// Get MD5 digest algorithm's MessageDigest's instance.
MessageDigest md = MessageDigest.getInstance(ALGORITHM_MD5);
byte[] b = md.digest(readyEncryptStr.getBytes());
int temp = 0;
// byte array switch hexadecimal number.
for (int offset = 0, bLen = b.length; offset < bLen; offset++) {
temp = b[offset];
if (temp < 0) {
temp += 256;
}
int d1 = temp / 16;
int d2 = temp % 16;
su.append(Integer.toHexString(d1) + Integer.toHexString(d2));
}
return su.toString();
} else {
return null;
}
}


/**
* MD5 32bit Encrypt Methods.
* 
* @param readyEncryptStr
*            ready encrypt string
* @return String encrypt result string
* @throws NoSuchAlgorithmException
*/
public static final String MD5_32bit2(String readyEncryptStr) throws NoSuchAlgorithmException {
if (readyEncryptStr != null) {
// The cipher text converted to hexadecimal string
StringBuilder su = new StringBuilder();
// Get MD5 digest algorithm's MessageDigest's instance.
MessageDigest md = MessageDigest.getInstance(ALGORITHM_MD5);
// Use specified byte update digest.
md.update(readyEncryptStr.getBytes());
byte[] b = md.digest();
int temp = 0;
// byte array switch hexadecimal number.
for (int offset = 0, bLen = b.length; offset < bLen; offset++) {
temp = b[offset];
if (temp < 0) {
temp += 256;
}
if (temp < 16) {
su.append("0");
}
su.append(Integer.toHexString(temp));
}
return su.toString();
} else {
return null;
}
}


/**
* MD5 16bit Encrypt Methods.
* 
* @param readyEncryptStr
*            ready encrypt string
* @return String encrypt result string
* @throws NoSuchAlgorithmException
* @throws UnsupportedEncodingException
*/
public static final String MD5_64bit(String readyEncryptStr)
throws NoSuchAlgorithmException, UnsupportedEncodingException {
MessageDigest md = MessageDigest.getInstance(ALGORITHM_MD5);
BASE64Encoder base64Encoder = new BASE64Encoder();
return base64Encoder.encode(md.digest(readyEncryptStr.getBytes(UTF_8)));
}


public static void main(String[] args) {
try {
String md516 = MD5.MD5_16bit("kaka123");
System.out.println("16bit-md5:\n" + md516); //
String md532 = MD5.MD5_32bit("kaka123");
String md5321 = MD5.MD5_32bit1("kaka123");
String md5322 = MD5.MD5_32bit2("kaka123");
System.out.println("32bit-md5:"); // 5d052f1e32af4e4ac2544a5fc2a9b992
System.out.println("1:  " + md532);
System.out.println("2:  " + md5321);
System.out.println("3:  " + md5322);
String md564 = MD5.MD5_64bit("kaka123");
System.out.println("64bit-md5:\n" + md564); //
} catch (Exception e) {
e.printStackTrace();
}
}
}