//psw：加密的文本，pswkey：加密的密碼，即密鑰
String psw="12345",pswkey="999";

//對(duì)該DES情況下加密，密鑰需要為56位難以人工由string為根據(jù)設(shè)定，因此這里：
//借助密鑰生成器，由new SecureRandom(pswkey.getBytes())，以pswkey為種子值生成密鑰
KeyGenerator keyGenerator=KeyGenerator.getInstance("DES");
keyGenerator.init(56,new SecureRandom(pswkey.getBytes()));
Key key=keyGenerator.generateKey();

//加密，DES/ECB/pkcs5padding為：算法/模式/填充 的參數(shù)
//參數(shù)new BouncyCastleProvider()也可修改為"BC"，要求前面要有Security.addProvider(new BouncyCastleProvider());
Cipher cipher=Cipher.getInstance("DES/ECB/pkcs5padding",new BouncyCastleProvider());
cipher.init(Cipher.ENCRYPT_MODE, key);
byte[] out=cipher.doFinal(psw.getBytes());
System.out.println(out);//字節(jié)數(shù)組，沒有編碼

//解密
Cipher cipher2=Cipher.getInstance("DES/ECB/pkcs5padding",new BouncyCastleProvider());
cipher2.init(Cipher.DECRYPT_MODE, key);
byte[] in=cipher2.doFinal(out);
System.out.println(new String(in));