Android实现DES对字符串加密

  import java.io.UnsupportedEncodingException;

  import java.security.SecureRandom;

  import javax.crypto.Cipher;

  import javax.crypto.SecretKey;

  import javax.crypto.SecretKeyFactory;

  import javax.crypto.spec.DESKeySpec;


  public class test

  {

  public static void main(String[] args)

  throws UnsupportedEncodingException

  {

  //待加密内容

  String str = “我是中国人”;

  //密码,长度要是8的倍数

  String password = “alnton08″;

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

  System.out.println(“加密后内容为:” + new String(result));

  //直接将如上内容解密

  try

  {

  byte[] decryResult = decrypt(result, password);

  System.out.println(“加密前内容为:” + new String(decryResult));

  }

  catch (Exception e1)

  {

  e1.printStackTrace();

  }

  }

  /**

  * <对字符串进行Des加密,将字符串转化为字节数组解密>

  */

  public static byte[] desCrypto(byte[] datasource, String password)

  {

  try

  {

  SecureRandom random = new SecureRandom();

  DESKeySpec desKey = new DESKeySpec(password.getBytes());

  //创建一个密匙工厂,然后用它把DESKeySpec转换成

  SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(“DES”);

  SecretKey securekey = keyFactory.generateSecret(desKey);

  //Cipher对象实际完成加密操作

  Cipher cipher = Cipher.getInstance(“DES”);

  //用密匙初始化Cipher对象

  cipher.init(Cipher.ENCRYPT_MODE, securekey, random);

  //现在,获取数据并加密

  //正式执行加密操作

  return cipher.doFinal(datasource);

  }

  catch (Throwable e)

  {

  e.printStackTrace();

  }

  return null;

  }

  /**

  * <将加密的密文字节数组转化为明文字节数组>

  */

  public static byte[] decrypt(byte[] src, String password)

  throws Exception

  {

  // DES算法要求有一个可信任的随机数源

  SecureRandom random = new SecureRandom();

  // 创建一个DESKeySpec对象

  DESKeySpec desKey = new DESKeySpec(password.getBytes());

  // 创建一个密匙工厂

  SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(“DES”);

  // 将DESKeySpec对象转换成SecretKey对象

  SecretKey securekey = keyFactory.generateSecret(desKey);

  // Cipher对象实际完成解密操作

  Cipher cipher = Cipher.getInstance(“DES”);

  // 用密匙初始化Cipher对象

  cipher.init(Cipher.DECRYPT_MODE, securekey, random);

  // 真正开始解密操作

  return cipher.doFinal(src);

  }

  }

你可能感兴趣的:(android)