JAVA加密技术的一个简单实现类

一个简单的完整实现类：

package com.potevio.telecom;

import java.security.MessageDigest;   

import javax.crypto.KeyGenerator;   
import javax.crypto.Mac;   
import javax.crypto.SecretKey;   
import javax.crypto.spec.SecretKeySpec;
  
import sun.misc.BASE64Decoder;   
import sun.misc.BASE64Encoder;   
  
/**
 *   
 * 基础加密组件 
 * @author Xian-JZ
 *
 */  
public abstract class Coder {   
    public static final String KEY_SHA = "SHA";   
    public static final String KEY_MD5 = "MD5";   
  
    /**  
     * MAC算法可选以下多种算法  
     *   
     * <pre>  
     * HmacMD5   
     * HmacSHA1   
     * HmacSHA256   
     * HmacSHA384   
     * HmacSHA512  
     * </pre>  
     */  
    public static final String KEY_MAC = "HmacMD5";   
  
    /**  
     * BASE64解密  
     *   
     * @param key  
     * @return  
     * @throws Exception  
     */  
    public static byte[] decryptBASE64(String key) throws Exception {   
        return (new BASE64Decoder()).decodeBuffer(key);   
    }   
  
    /**  
     * BASE64加密  
     *   
     * @param key  
     * @return  
     * @throws Exception  
     */  
    public static String encryptBASE64(byte[] key) throws Exception {   
        return (new BASE64Encoder()).encodeBuffer(key);   
    }   
  
    /**  
     * MD5加密  
     *   
     * @param data  
     * @return  
     * @throws Exception  
     */  
    public static byte[] encryptMD5(byte[] data) throws Exception {   
  
        MessageDigest md5 = MessageDigest.getInstance(KEY_MD5);   
        md5.update(data);   
  
        return md5.digest();   
  
    }   
  
    /**  
     * SHA加密  
     *   
     * @param data  
     * @return  
     * @throws Exception  
     */  
    public static byte[] encryptSHA(byte[] data) throws Exception {   
  
        MessageDigest sha = MessageDigest.getInstance(KEY_SHA);   
        sha.update(data);   
  
        return sha.digest();   
  
    }   
  
    /**  
     * 初始化HMAC密钥  
     *   
     * @return  
     * @throws Exception  
     */  
    public static String initMacKey() throws Exception {   
        KeyGenerator keyGenerator = KeyGenerator.getInstance(KEY_MAC);   
  
        SecretKey secretKey = keyGenerator.generateKey();   
        return encryptBASE64(secretKey.getEncoded());   
    }   
  
    /**  
     * HMAC加密  
     *   
     * @param data  
     * @param key  
     * @return  
     * @throws Exception  
     */  
    public static byte[] encryptHMAC(byte[] data, String key) throws Exception {   
  
        SecretKey secretKey = new SecretKeySpec(decryptBASE64(key), KEY_MAC);   
        Mac mac = Mac.getInstance(secretKey.getAlgorithm());   
        mac.init(secretKey);   
  
        return mac.doFinal(data);   
  
    }   
}  

 测试类：

package com.potevio.telecom;

import static org.junit.Assert.*;

import java.math.BigInteger;

import org.junit.Test;

/**
 * 加密测试类
 * @author Xian-JZ
 *
 */
public class CoderTest {

    @Test  
    public void test() throws Exception {   
        String inputStr = "简单加密";   
        System.err.println("原文:\n" + inputStr);   
  
        byte[] inputData = inputStr.getBytes();   
        String code = Coder.encryptBASE64(inputData);   
  
        System.err.println("BASE64加密后:\n" + code);   
  
        byte[] output = Coder.decryptBASE64(code);   
  
        String outputStr = new String(output);   
  
        System.err.println("BASE64解密后:\n" + outputStr);   
  
        // 验证BASE64加密解密一致性   
        assertEquals(inputStr, outputStr);   
  
        // 验证MD5对于同一内容加密是否一致   
        assertArrayEquals(Coder.encryptMD5(inputData), Coder   
                .encryptMD5(inputData));   
  
        // 验证SHA对于同一内容加密是否一致   
        assertArrayEquals(Coder.encryptSHA(inputData), Coder   
                .encryptSHA(inputData));   
  
        String key = Coder.initMacKey();   
        System.err.println("Mac密钥:\n" + key);   
  
        // 验证HMAC对于同一内容，同一密钥加密是否一致   
        assertArrayEquals(Coder.encryptHMAC(inputData, key), Coder.encryptHMAC(   
                inputData, key));   
  
        BigInteger md5 = new BigInteger(Coder.encryptMD5(inputData));   
        System.err.println("MD5:\n" + md5.toString(16));   
  
        BigInteger sha = new BigInteger(Coder.encryptSHA(inputData));   
        System.err.println("SHA:\n" + sha.toString(32));   
  
        BigInteger mac = new BigInteger(Coder.encryptHMAC(inputData, inputStr));   
        System.err.println("HMAC:\n" + mac.toString(16));   
    }   

}

 控制台输出：

原文:
简单加密
BASE64加密后:
vPK1pbzTw9w=

BASE64解密后:
简单加密
Mac密钥:
xVd3YjIn6IqYrzQHvJLN2oOA8pBxsFrDC/ynBrqBFguN920ghN40SMctn9vs6yh5Ut46JRZWn+7y
6fpc9d1Qbw==

MD5:
-12d1456f5d947be6eac80fc07900be99
SHA:
-bbbd559051qu2b5pl635l3jj8jrvodsn
HMAC:
358250966fbd6166b94b384105f6894b