加密
代碼有詳細解釋，不多廢話。
註意：DES加密和解密過程中，密鑰長度都必須是8的倍數
[java] view plain copy
public byte[] desCrypto(byte[] datasource, String password) {
try{
SecureRandom random = new SecureRandom();
DESKeySpec desKey = new DESKeySpec(password.getBytes());
//創建壹個密匙工廠，然後用它把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，獲取數據並加密
//正式執行加密操作
return cipher.doFinal(datasource);
}catch(Throwable e){
e.printStackTrace();
}
return null;
}
解密
代碼有詳細註釋，不多廢話
[java] view plain copy
private byte[] decrypt(byte[] src, String password) throws Exception {
// DES算法要求有壹個可信任的隨機數源
SecureRandom random = new SecureRandom();
// 創建壹個DESKeySpec對象
DESKeySpec desKey = new DESKeySpec(password.getBytes());
// 創建壹個密匙工廠
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);
}
測試場景
例如，我們可以利用如上函數對字符串進行加密解密，也可以對文件進行加密解密，如：
[java] view plain copy
//待加密內容
String str = "測試內容";
//密碼，長度要是8的倍數
String password = "12345678";
byte[] result = DESCrypto.desCrypto(str.getBytes(),password);
System.out.println("加密後內容為："+new String(result));
//直接將如上內容解密
try {
byte[] decryResult = des.decrypt(result, password);
System.out.println("加密後內容為："+new String(decryResult));
} catch (Exception e1) {
e1.printStackTrace();
}