java中DES加密解密

废话不多说，直接奉上代码：

代码一

package com.eabax.plugin.yundada.utils;
import java.io.IOException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.spec.InvalidKeySpecException;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import org.apache.commons.codec.binary.Base64;
import sun.misc.BASE64Decoder;
public class DESEncryptHelper {
  private final static String DES = "DES";
  /**
   * 生成密钥
   * @param employeeCode
   */
  public static String getDESKey(String encryptStr){
    if (!CacheManager.getCache().containsKey("encryptKey_"+encryptStr)) {
      CacheManager.getCache().put("encryptKey_"+encryptStr, encryptStr+"tablemiyaokey");
    }
    String key = (String) CacheManager.getCache().get("encryptKey_"+encryptStr);
    return key;
  }
   /**
   * Description 根据键值进行解密
   * @param data
   * @param key 加密键byte数组
   * @return
   * @throws IOException
   * @throws Exception
   */
  public static String decrypt(String data, String key) throws IOException,
      Exception {
    if (data == null)
      return null;
    BASE64Decoder decoder = new BASE64Decoder();
    byte[] buf = decoder.decodeBuffer(data);
    byte[] bt = decrypt(buf,key.getBytes());
    return new String(bt);
  }
  /**
   * 对字符串加密 
   * @param str
   * @return
   * @throws InvalidKeyException
   * @throws IllegalBlockSizeException
   * @throws BadPaddingException
   * @throws InvalidKeySpecException
   * @throws NoSuchAlgorithmException
   * @throws NoSuchPaddingException
   */
  public static String getEncryptStr(String str,String encryptStr) throws InvalidKeyException,
      IllegalBlockSizeException, BadPaddingException,
      InvalidKeySpecException, NoSuchAlgorithmException,
      NoSuchPaddingException {
    //获取key
    String key = getDESKey(encryptStr);
    //获取密钥
    SecretKeyFactory factory = SecretKeyFactory.getInstance("DES");
    DESKeySpec keyspec = new DESKeySpec(key.getBytes());
    SecretKey deskey = factory.generateSecret(keyspec);
    // Cipher负责完成加密或解密工作
    Cipher c = Cipher.getInstance("DES");
    // 根据密钥，对Cipher对象进行初始化，DECRYPT_MODE表示加密模式 
    c.init(Cipher.ENCRYPT_MODE, deskey);
    byte[] src = str.getBytes();
    // 该字节数组负责保存加密的结果
    byte[] cipherByte = c.doFinal(src);
    String enstr = new String(Base64.encodeBase64(cipherByte));
    return enstr;
  }
   /**
   * Description 根据键值进行解密
   * @param data
   * @param key 加密键byte数组
   * @return
   * @throws Exception
   */
  private static byte[] decrypt(byte[] data, byte[] key) throws Exception {
    // 生成一个可信任的随机数源
    SecureRandom sr = new SecureRandom();
    // 从原始密钥数据创建DESKeySpec对象
    DESKeySpec dks = new DESKeySpec(key);
    // 创建一个密钥工厂，然后用它把DESKeySpec转换成SecretKey对象
    SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);
    SecretKey securekey = keyFactory.generateSecret(dks);
    // Cipher对象实际完成解密操作
    Cipher cipher = Cipher.getInstance(DES);
    // 用密钥初始化Cipher对象
    cipher.init(Cipher.DECRYPT_MODE, securekey, sr);
    return cipher.doFinal(data);
  }
}

代码二

package com.sinosoft.olyvem.common;

import java.security.SecureRandom;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;

import sun.misc.BASE64Encoder;

public class DES ...{
  private byte[] desKey;

  public DES(byte[] desKey) ...{
    this.desKey = desKey;
  }

  public byte[] doEncrypt(byte[] plainText) throws Exception ...{
    // DES算法要求有一个可信任的随机数源
    SecureRandom sr = new SecureRandom();
    byte rawKeyData[] = desKey;/**//* 用某种方法获得密匙数据 */
    // 从原始密匙数据创建DESKeySpec对象
    DESKeySpec dks = new DESKeySpec(rawKeyData);
    // 创建一个密匙工厂，然后用它把DESKeySpec转换成
    // 一个SecretKey对象
    SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
    SecretKey key = keyFactory.generateSecret(dks);
    // 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, key, sr);
    // 现在，获取数据并加密
    byte data[] = plainText;/**//* 用某种方法获取数据 */
    // 正式执行加密操作
    byte encryptedData[] = cipher.doFinal(data);
    return encryptedData;
  }

  public byte[] doDecrypt(byte[] encryptText) throws Exception ...{
    // DES算法要求有一个可信任的随机数源
    SecureRandom sr = new SecureRandom();
    byte rawKeyData[] = desKey; /**//* 用某种方法获取原始密匙数据 */
    // 从原始密匙数据创建一个DESKeySpec对象
    DESKeySpec dks = new DESKeySpec(rawKeyData);
    // 创建一个密匙工厂，然后用它把DESKeySpec对象转换成
    // 一个SecretKey对象
    SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
    SecretKey key = keyFactory.generateSecret(dks);
    // 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, key, sr);
    // 现在，获取数据并解密
    byte encryptedData[] = encryptText;/**//* 获得经过加密的数据 */
    // 正式执行解密操作
    byte decryptedData[] = cipher.doFinal(encryptedData);
    return decryptedData;
  }

  public static void main(String[] args) throws Exception ...{
    String key = "FtpXPass";
    String value = "olympic";
    BASE64Encoder base64Encoder = new BASE64Encoder();

    DES desEncrypt = new DES(key.getBytes());
    byte[] encryptText = desEncrypt.doEncrypt(value.getBytes());
    //System.out.println("doEncrypt  -  " + toHexString(encryptText));
    System.out.println("doEncrypt  -  "
        + base64Encoder.encode(encryptText));
    byte[] decryptText = desEncrypt.doDecrypt("r9NGYcKAtdo=".getBytes());
    System.out.println("doDecrypt  -  " + new String(decryptText));
    //System.out.println("doDecrypt  -  " + toHexString(decryptText));

  }

  public static String toHexString(byte[] value) ...{
    String newString = "";
    for (int i = 0; i < value.length; i++) ...{
      byte b = value[i];
      String str = Integer.toHexString(b);
      if (str.length() > 2) ...{
        str = str.substring(str.length() - 2);
      }
      if (str.length() < 2) ...{
        str = "0" + str;
      }
      newString += str;
    }
    return newString.toUpperCase();
  }

}

以上就是本文关于DES加密解密的代码了，希望对大家学习java有所帮助。