Java DES加密解密工具類

    import java.security.InvalidKeyException;

    import java.security.Key;

    import java.security.NoSuchAlgorithmException;


import javax.crypto.BadPaddingException;  
import javax.crypto.Cipher;  
import javax.crypto.IllegalBlockSizeException;  
import javax.crypto.NoSuchPaddingException;  
import javax.crypto.spec.SecretKeySpec;  

import org.apache.commons.codec.binary.Base64;  

public class DES {  

    public DES() {  
    }  

    public static DES getInstance(String key) throws NoSuchPaddingException,  
            NoSuchAlgorithmException {  
        return getInstance(getKeyByStr(key));  
    }  

    public static DES getInstance(byte key[]) throws NoSuchPaddingException,  
            NoSuchAlgorithmException {  
        DES des = new DES();  
        if (des.key == null) {  
            SecretKeySpec spec = new SecretKeySpec(key, "DES");  
            des.key = spec;  
        }  
        des.cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");  
        return des;  
    }  

    public byte[] encrypt(byte b[]) throws InvalidKeyException,  
            BadPaddingException, IllegalBlockSizeException,  
            IllegalStateException {  
        byte byteFina[] = null;  
        cipher.init(1, key);  
        byteFina = cipher.doFinal(b);  
        return byteFina;  
    }  

    public byte[] decrypt(byte b[]) throws InvalidKeyException,  
            BadPaddingException, IllegalBlockSizeException,  
            IllegalStateException {  
        byte byteFina[] = null;  
        cipher.init(2, key);  
        byteFina = cipher.doFinal(b);  
        return byteFina;  
    }  

    public static byte[] getKeyByStr(String str) {  
        byte bRet[] = new byte[str.length() / 2];  
        for (int i = 0; i < str.length() / 2; i++) {  
            Integer itg = new Integer(16 * getChrInt(str.charAt(2 * i))  
                    + getChrInt(str.charAt(2 * i + 1)));  
            bRet[i] = itg.byteValue();  
        }  
        return bRet;  
    }  

    private static int getChrInt(char chr) {  
        int iRet = 0;  
        if (chr == "0".charAt(0))  
            iRet = 0;  
        if (chr == "1".charAt(0))  
            iRet = 1;  
        if (chr == "2".charAt(0))  
            iRet = 2;  
        if (chr == "3".charAt(0))  
            iRet = 3;  
        if (chr == "4".charAt(0))  
            iRet = 4;  
        if (chr == "5".charAt(0))  
            iRet = 5;  
        if (chr == "6".charAt(0))  
            iRet = 6;  
        if (chr == "7".charAt(0))  
            iRet = 7;  
        if (chr == "8".charAt(0))  
            iRet = 8;  
        if (chr == "9".charAt(0))  
            iRet = 9;  
        if (chr == "A".charAt(0))  
            iRet = 10;  
        if (chr == "B".charAt(0))  
            iRet = 11;  
        if (chr == "C".charAt(0))  
            iRet = 12;  
        if (chr == "D".charAt(0))  
            iRet = 13;  
        if (chr == "E".charAt(0))  
            iRet = 14;  
        if (chr == "F".charAt(0))  
            iRet = 15;  
        return iRet;  
    }  

    private Key key;  
    private Cipher cipher;  

    /** 
     * @interpret 進行base64加密操作 
     * @param text 
     * @param keyString 
     * @return String 
     */  
    public String encrypt(String text, String keyString) {  
        String body = null;  

        try {  
            DES des = DES.getInstance(keyString);  

            byte[] b = des.encrypt(text.getBytes("UTF8"));  
            body = new String(Base64.encodeBase64(b));  
        } catch (Exception ex) {  

        }  
        return body;  
    }  

    /** 
     * @interpret 進行base64進行解密 
     * @param text 
     * @param keyString 
     * @return String 
     */  
    public String decrypt(String text, String keyString) {  
        String body = null;  
        try {  
            DES des = DES.getInstance(keyString);  

            byte[] b = Base64.decodeBase64(text.getBytes());  

            body = new String(des.decrypt(b), "UTF8");  
        } catch (Exception e) {  
            e.printStackTrace();  
        }  
        return body;  
    }  

    public String authcode(String content, String operation, String key){  

        String encontent = null;  
        if (operation != null && operation.equals("DECODE")) {  
            encontent = encrypt(content,key);  
        } else if (operation != null && operation.equals("ENCODE")) {  
            encontent = decrypt(content,key);  
        }  
        return encontent;  
    }  

    public static void main(String[] args) {  
        DES des = new DES();  
        System.out.println(des.authcode("wewweewewew=","DECODE","0102030405060708"));//加密  
        System.out.println(des.authcode("d8fPhfd9JkW99p8aqhtVIA==","ENCODE","0102030405060708"));//解密  
    }  
}  </pre>