java Encryption&Decryption

The encryption class:

package cn.com.smartcost.qy.util;

import java.security.Key;  
import java.security.Security;  
  
import javax.crypto.Cipher;  
  
/** 
 * encrypt and decryption
 * @author wangfeng 
 * @since 2013-4-27 15:50:26 
 * @version 1.0 
 * 
 */  
public class EncryptionDecryption {  
    private static String strDefaultKey = "wfkey";  
      
  //encrypt 
    private Cipher encryptCipher = null;  
      
  // decryption  
    private Cipher decryptCipher = null;  
      
    /** 
     * byte array to hexadecimal
     * @param arrB 
     * @return 16 
     * @throws Exception 
     */  
    public static String byteArr2HexStr(byte[] arrB) throws Exception{  
        int bLen = arrB.length;  
        //
        StringBuffer strBuffer = new StringBuffer(bLen*2);  
        for(int i=0; i != bLen; ++i){  
            int intTmp = arrB[i];  
            //
            while(intTmp < 0){  
                intTmp = intTmp + 256;//
            }  
            //
            if(intTmp < 16){  
                strBuffer.append("0");  
            }  
            strBuffer.append(Integer.toString(intTmp,16));  
        }  
        return strBuffer.toString();  
    }  
      
      
    /** 
     * hex to byte array
     * @param hexStr 
     * @return 
     * @throws Exception 
     */  
    public static byte[] hexStr2ByteArr(String hexStr) throws Exception{  
        byte[] arrB = hexStr.getBytes();  
        int bLen = arrB.length;  
        byte[] arrOut = new byte[bLen/2];  
        for(int i=0; i<bLen; i = i+2){  
            String strTmp = new String(arrB,i,2);  
            arrOut[i/2] = (byte)Integer.parseInt(strTmp,16);  
        }  
        return arrOut;  
    }  
      
    /** 
     * encrypt
     * @throws Exception 
     */  
    public EncryptionDecryption() throws Exception {  
        this(strDefaultKey);  
    }  
  
      
      
    /** 
     * encryption
     * @param strKey
     * @throws Exception 
     */  
       @SuppressWarnings("restriction")  
    public EncryptionDecryption(String strKey) throws Exception {  
            Security.addProvider(new com.sun.crypto.provider.SunJCE());  
            Key key = getKey(strKey.getBytes());  
  
            encryptCipher = Cipher.getInstance("DES");  
            encryptCipher.init(Cipher.ENCRYPT_MODE, key);  
  
            decryptCipher = Cipher.getInstance("DES");  
            decryptCipher.init(Cipher.DECRYPT_MODE, key);  
        }  
  
    /** 
     * encrypt
     * @param arrB 
     * @return 
     * @throws Exception 
     */  
    public byte[] encrypt(byte[] arrB) throws Exception{  
        return encryptCipher.doFinal(arrB);  
    }  
      
    /** 
     * encrypt
     * @param strIn 
     * @return
     * @throws Exception 
     */  
    public String encrypt(String strIn) throws Exception{  
        return byteArr2HexStr(encrypt(strIn.getBytes()));  
    }  
      
    /** 
     * decrypt
     * @param arrB 
     * @return  
     * @throws Exception 
     */  
    public byte[] decrypt(byte[] arrB) throws Exception{  
        return decryptCipher.doFinal(arrB);  
    }  
      
    /** 
     * decrypt 
     * @param strIn 
     * @return 
     * @throws Exception 
     */  
    public String decrypt(String strIn) throws Exception{  
        try{  
            return new String(decrypt(hexStr2ByteArr(strIn)));  
        }catch (Exception e) {  
            return "";  
        }  
    }  
      
      
    /** 
     * get the key
     * @param arrBTmp 
     * @return 
     * @throws Exception 
     */  
    private Key getKey(byte[] arrBTmp) throws Exception{  
        byte[] arrB = new byte[8]; //  
        for(int i=0; i<arrBTmp.length && i < arrB.length; ++i){  
            arrB[i] = arrBTmp[i];  
        }  
          
        //
        Key key = new javax.crypto.spec.SecretKeySpec(arrB,"DES");  
        return key;  
    }  
      
} 

　　Attention:

This class nees a jar:sunjce_provider.jar. u can download it from here: http://pan.baidu.com/s/1ntqkU4h

To use:

private EncryptionDecryption des = new  EncryptionDecryption("wang");
//encrypt
String password = "123456";
password = des.encrypt(password);
//decrypt
password =des.decrypt(password);