Java常用加密算法工具类

import java.io.IOException;
import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

/**
* 常用加密算法工具类
* @author cq
*/
public class EncryptUtils {

/**
* 用MD5算法进行加密
* @param str 需要加密的字符串
* @return MD5加密后的结果
*/
public static String encodeMD5String(String str) {
return encode(str, "MD5");
}

/**
* 用SHA算法进行加密
* @param str 需要加密的字符串
* @return SHA加密后的结果
*/
public static String encodeSHAString(String str) {
return encode(str, "SHA");
}

/**
* 用base64算法进行加密
* @param str 需要加密的字符串
* @return base64加密后的结果
*/
public static String encodeBase64String(String str) {
BASE64Encoder encoder =  new BASE64Encoder();
return encoder.encode(str.getBytes());
}

/**
* 用base64算法进行解密
* @param str 需要解密的字符串
* @return base64解密后的结果
* @throws IOException
*/
public static String decodeBase64String(String str) throws IOException {
BASE64Decoder encoder =  new BASE64Decoder();
return new String(encoder.decodeBuffer(str));
}

private static String encode(String str, String method) {
MessageDigest md = null;
String dstr = null;
try {
md = MessageDigest.getInstance(method);
md.update(str.getBytes());
dstr = new BigInteger(1, md.digest()).toString(16);
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
return dstr;
}

public static void main(String[] args) throws IOException {
String user = "oneadmin";
System.out.println("原始字符串 " + user);
System.out.println("MD5加密 " + encodeMD5String(user));
System.out.println("SHA加密 " + encodeSHAString(user));
String base64Str = encodeBase64String(user);
System.out.println("Base64加密 " + base64Str);
System.out.println("Base64解密 " + decodeBase64String(base64Str));
}
}