JavaDES加密解密算法

    import java.nio.ByteBuffer;  
    import java.security.SecureRandom;  

    import javax.crypto.Cipher;  
    import javax.crypto.SecretKey;  
    import javax.crypto.SecretKeyFactory;  
    import javax.crypto.spec.DESKeySpec;  
    /** 
     *  
     * @author whzhaochao 
     *  
     * DES加密解密 
     * 
     */  
    public class Main {  

        public static void main(String[] args) throws Exception {  
            // TODO Auto-generated method stub  

            // 待加密內容  
            String str = "要加密的內容";  
            // 密碼，長度要是8的倍數  
            String password = "9876543210";  

            String codeStr=CodeStr(str, password);  
            System.out.println("原始內容："+str);  
            System.out.println("加密內容："+codeStr);  
            String deCodeStr=DcodeStr(codeStr, password);  
            System.out.println("解密內容："+deCodeStr);  


        }  
        /** 
         *  
         * @param str 待加密字符串 
         * @param password 密碼 
         * @return 
         */  

        public static String CodeStr(String str,String password){  

            byte[] result = desCrypto(str.getBytes(), password);  

            char[] chreslut=new char[result.length];  
            for(int i=0; i<result.length;i++){  
                char ch=(char) result[i];  
                chreslut[i]=ch;  
            }  
            String strres=new String(chreslut);  
            return strres;  
        }  
        /** 
         *  
         * @param strres  待解密字符串 
         * @param password  密碼 
         * @return 
         * @throws Exception 
         */  
        public static String DcodeStr(String strres,String password) throws Exception{  
            byte [] decode=new byte[strres.length()];  

            for(int i=0;i<strres.length();i++){  
                char ch=strres.charAt(i);  
                byte b=(byte) ch;  
                decode[i]=b;  

            }  
             byte[] decryResult = decrypt(decode, password);  
            return new String(decryResult);  
        }  
        /** 
         *  
         * @param datasource  
         * @param password 
         * @return 
         */  
        public static byte[] desCrypto(byte[] datasource, String password) {  


            try {  
                SecureRandom random = new SecureRandom();  
                DESKeySpec desKey = new DESKeySpec(password.getBytes());  
                // 創建一個密匙工廠，然后用它把DESKeySpec轉換成  
                SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");  
                SecretKey securekey = keyFactory.generateSecret(desKey);  
                // Cipher對象實際完成加密操作  
                Cipher cipher = Cipher.getInstance("DES");  
                // 用密匙初始化Cipher對象  
                cipher.init(Cipher.ENCRYPT_MODE, securekey, random);  
                // 現在，獲取數據并加密  
                // 正式執行加密操作  
                return cipher.doFinal(datasource);  
            } catch (Throwable e) {  
                e.printStackTrace();  
            }  
            return null;  
        }  
        /** 
         *  
         * @param src 
         * @param password 
         * @return 
         * @throws Exception 
         */  

        private static byte[] decrypt(byte[] src, String password) throws Exception {  
            // DES算法要求有一個可信任的隨機數源  
            SecureRandom random = new SecureRandom();  
            // 創建一個DESKeySpec對象  
            DESKeySpec desKey = new DESKeySpec(password.getBytes());  
            // 創建一個密匙工廠  
            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");  
            // 將DESKeySpec對象轉換成SecretKey對象  
            SecretKey securekey = keyFactory.generateSecret(desKey);  
            // Cipher對象實際完成解密操作  
            Cipher cipher = Cipher.getInstance("DES");  
            // 用密匙初始化Cipher對象  
            cipher.init(Cipher.DECRYPT_MODE, securekey, random);  
            // 真正開始解密操作  
            return cipher.doFinal(src);  
        }  
    }