DESUtil.java

import java.io.IOException;
import java.security.SecureRandom;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;


public class DESUtil {

		/**
	    *  根据键值进行加密
	    */
	    public static String encrypt(String data, String key) throws Exception {
	        byte[] bt = encrypt(data.getBytes(), key.getBytes());
	        String strs = HexUtil.bytes2HexStr( bt );
	        return strs;
	    }

	    /**
	    *  根据键值进行解密
	    */
	    public static String decrypt(String data, String key) throws IOException, Exception {
	    	if (data == null)
	    	{
	    		return null;
	    	}

	    	byte[] buf = HexUtil.hexStr2Bytes( data );
	        byte[] bt = decrypt(buf, key.getBytes());
	        return new String(bt);
	    }

	    /**
	    *  根据键值进行加密
	    */
	    private static byte[] encrypt(byte[] data, byte[] key) throws Exception {
	        Cipher cipher = cipherInit(data, key, Cipher.ENCRYPT_MODE);
	        return cipher.doFinal(data);
	    }

	    /**
	    *  根据键值进行解密
	    */
	    private static byte[] decrypt(byte[] data, byte[] key) throws Exception {
	        Cipher cipher = cipherInit(data, key, Cipher.DECRYPT_MODE);
	        return cipher.doFinal(data);
	    }

	    private static Cipher cipherInit(byte[] data, byte[] key,int cipherValue) throws Exception {
	        /** 生成一个可信任的随机数源**/
	        SecureRandom sr = new SecureRandom();

	        /** 从原始密钥数据创建DESKeySpec对象**/
	        DESKeySpec dks = new DESKeySpec(key);

	        /** 创建一个密钥工厂，然后用它把DESKeySpec转换成SecretKey对象**/
	        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
	        SecretKey securekey = keyFactory.generateSecret(dks);

	        /** Cipher对象实际完成加密或解密操作**/
	        Cipher cipher = Cipher.getInstance("DES");
	        /**用密钥初始化Cipher对象**/
	        cipher.init(cipherValue, securekey, sr);
	        return cipher;
	    }
	    
	    /*
	     * 加密
	     */
	    static final String key = "nykjxnlc";
	    public static String encryptHex( String data ){
	    	String outstr ="";
	    	try {
	    		outstr = encrypt(data, key);
			} catch (Exception e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}

	    	return outstr;
	    }
	    
	    /*
	     * 解密
	     */
	    public static String decryptHex( String data ){
	    	String outstr ="";
	    	try {
	    		outstr = decrypt( data, key);
			} catch (Exception e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
	    	
	    	return outstr;
	    }
	    
	    public static void main(String[] args) throws Exception {

	    	String data="6107470767063040|13521746902|145613450355";
	    	String str = encryptHex( data );
	    	System.out.println( data +" : "+ str );
	    	
	    	String dstr = decryptHex( str );
	    	System.out.println( str +" : "+dstr );

	    	
	    	/*
	        String data = "13264034035";
	        String key = "38156403";
	        System.err.println(encrypt(data, key));
	        System.err.println( decrypt(encrypt(data, key), key) );
	        System.out.println( HexUtil.bytes2HexStr(encrypt(data, key).getBytes()) );
	        
	        String str=new String ( HexUtil.hexStr2Bytes( HexUtil.bytes2HexStr(encrypt(data, key).getBytes()) ));
	        System.out.println( str );
	        System.out.println( decrypt( str, key) );
	        */
	    }
}