DES加密解密和MD5加密解密算法

DES加密解密

import java.security.Key;
import java.security.SecureRandom;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

/**  
 *   
 * 使用DES加密与解密,可对byte[],String类型进行加密与解密 密文可使用String,byte[]存储.  
 *   
 * 方法: void getKey(String strKey)从strKey的字条生成一个Key  
 *   
 * String getEncString(String strMing)对strMing进行加密,返回String密文 String  
 * getDesString(String strMi)对strMin进行解密,返回String明文  
 *   
 * byte[] getEncCode(byte[] byteS)byte[]型的加密 byte[] getDesCode(byte[]  
 * byteD)byte[]型的解密  
 */  
  
public class ThreeDES {   
    Key key;   
  
    /**  
     * 根据参数生成KEY  
     *   
     * @param strKey  
     */  
    public void getKey(String strKey) {   
        try {   
            KeyGenerator _generator = KeyGenerator.getInstance("DES");   
            _generator.init(new SecureRandom(strKey.getBytes()));   
            this.key = _generator.generateKey(); 
            _generator = null;   
        } catch (Exception e) {   
            e.printStackTrace();   
        }   
    }   
  
    /**  
     * 加密String明文输入,String密文输出  
     *   
     * @param strMing  
     * @return  
     */  
    public String getEncString(String strMing) {   
        byte[] byteMi = null;   
        byte[] byteMing = null;   
        String strMi = "";   
        BASE64Encoder base64en = new BASE64Encoder();   
        try {   
            byteMing = strMing.getBytes("UTF8");   
            byteMi = this.getEncCode(byteMing);   
            strMi = base64en.encode(byteMi);   
        } catch (Exception e) {   
            e.printStackTrace();   
        } finally {   
            base64en = null;   
            byteMing = null;   
            byteMi = null;   
        }   
        return strMi;   
    }   
  
    /**  
     * 解密 以String密文输入,String明文输出  
     *   
     * @param strMi  
     * @return  
     */  
    public String getDesString(String strMi) {   
        BASE64Decoder base64De = new BASE64Decoder();   
        byte[] byteMing = null;   
        byte[] byteMi = null;   
        String strMing = "";   
        try {   
            byteMi = base64De.decodeBuffer(strMi);   
            byteMing = this.getDesCode(byteMi);   
            strMing = new String(byteMing, "UTF8");   
        } catch (Exception e) {   
            e.printStackTrace();   
        } finally {   
            base64De = null;   
            byteMing = null;   
            byteMi = null;   
        }   
        return strMing;   
    }   
  
    /**  
     * 加密以byte[]明文输入,byte[]密文输出  
     *   
     * @param byteS  
     * @return  
     */  
    private byte[] getEncCode(byte[] byteS) {   
        byte[] byteFina = null;   
        Cipher cipher;   
        try {   
            cipher = Cipher.getInstance("DES");   
            cipher.init(Cipher.ENCRYPT_MODE, key);   
            byteFina = cipher.doFinal(byteS);   
        } catch (Exception e) {   
            e.printStackTrace();   
        } finally {   
            cipher = null;   
        }   
        return byteFina;   
    }   
  
    /**  
     * 解密以byte[]密文输入,以byte[]明文输出  
     *   
     * @param byteD  
     * @return  
     */  
    private byte[] getDesCode(byte[] byteD) {   
        Cipher cipher;   
        byte[] byteFina = null;   
        try {   
            cipher = Cipher.getInstance("DES");   
            cipher.init(Cipher.DECRYPT_MODE, key);   
            byteFina = cipher.doFinal(byteD);   
        } catch (Exception e) {   
            e.printStackTrace();   
        } finally {   
            cipher = null;   
        }   
        return byteFina;   
  
    }   
  
    public static void main(String[] args) {   
        ThreeDES des = new ThreeDES();// 实例化一个对像   
        des.getKey("daliantan0v0");// 生成密匙   
        
        System.out.println("=================对字符串加密==================================");
        String strEnc = des.getEncString("wuzhaohui");// 加密字符串,返回String的密文   
        System.out.println(strEnc);   
  
        String strDes = des.getDesString("/RubFP0okb6u6s2INMttNQ==");// 把String 类型的密文解密    
        System.out.println(strDes);   
        
        System.out.println("==================对字节数组加密=================================");
       /*
        byte[] getEncCode(byte[] byteS)byte[]型的加密 byte[] getDesCode(byte[]  
                                                                         * byteD)byte[]型的解密
                                                            */
                                                                         
    }   
  
} 

测试结果：

=================对字符串加密==================================
/RubFP0okb6u6s2INMttNQ==
wuzhaohui
==================对字节数组加密=================================

MD5加密

package MD5;
import java.security.MessageDigest;


public class MD5andKL {
 // MD5加码。32位
 public static String MD5Encode(String inStr) {
  MessageDigest md5 = null;
  try {
   md5 = MessageDigest.getInstance("MD5");
  } catch (Exception e) {
   System.out.println(e.toString());
   e.printStackTrace();
   return "";
  }
  char[] charArray = inStr.toCharArray();
  byte[] byteArray = new byte[charArray.length];

  for (int i = 0; i < charArray.length; i++)
   byteArray[i] = (byte) charArray[i];

  byte[] md5Bytes = md5.digest(byteArray);

  StringBuffer hexValue = new StringBuffer();

  for (int i = 0; i < md5Bytes.length; i++) {
   int val = ((int) md5Bytes[i]) & 0xff;
   if (val < 16)
    hexValue.append("0");
   hexValue.append(Integer.toHexString(val));
  }

  return hexValue.toString();
 }

 // 可逆的加密算法
 public static String KL(String inStr) {
  // String s = new String(inStr);
  char[] a = inStr.toCharArray();
  for (int i = 0; i < a.length; i++) {
   a[i] = (char) (a[i] ^ 't');
  }
  String s = new String(a);
  return s;
 }

 // 加密后解密
 public static String MD5DecCode(String inStr) {
  char[] a = inStr.toCharArray();
  for (int i = 0; i < a.length; i++) {
   a[i] = (char) (a[i] ^ 't');
  }
  String k = new String(a);
  return k;
 }
 
 // 测试主函数
 public static void main(String args[]) {
  String s = new String("a");
  System.out.println("原始：" + s);
  System.out.println("MD5后：" + MD5Encode(s));
  System.out.println("MD5后再加密：" + KL(MD5Encode(s)));
  System.out.println("解密为MD5后的：" + MD5DecCode(KL(MD5Encode(s))));
 }
}

测试结果：

原始：a
MD5后：0cc175b9c0f1b6a831c399e269772661
MD5后再加密：DECAMDEBLGEGMMFBMCCFBBE
解密为MD5后的：0cc175b9c0f1b6a831c399e269772661