des加密 企业常用的算法加密

package com.wtfypm;
import java.security.Key;
import java.security.SecureRandom;
import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
public class DesEncrypt {
Key key;
/**
  * 根据参数生成KEY
  *
  * @param strKey
  */
public void getKey(String strKey) {
  try {
   KeyGenerator _generator = KeyGenerator.getInstance("DES");
   _generator.init(new SecureRandom(strKey.getBytes()));
   this.key = _generator.generateKey();
   _generator = null;
  } catch (Exception e) {
   e.printStackTrace();
  }
}
/**
  * 加密String明文输入,String密文输出
  *
  * @param strMing
  * @return
  */
public String getEncString(String strMing) {
  byte[] byteMi = null;
  byte[] byteMing = null;
  String strMi = "";
  try {
   return byte2hex(getEncCode(strMing.getBytes()));
   // byteMing = strMing.getBytes("UTF8");
   // byteMi = this.getEncCode(byteMing);
   // strMi = new String( byteMi,"UTF8");
  } catch (Exception e) {
   e.printStackTrace();
  } finally {
   byteMing = null;
   byteMi = null;
  }
  return strMi;
}
/**
  * 解密 以String密文输入,String明文输出
  *
  * @param strMi
  * @return
  */
public String getDesString(String strMi) {
  byte[] byteMing = null;
  byte[] byteMi = null;
  String strMing = "";
  try {
   return new String(getDesCode(hex2byte(strMi.getBytes())));
   // byteMing = this.getDesCode(byteMi);
   // strMing = new String(byteMing,"UTF8");
  } catch (Exception e) {
   e.printStackTrace();
  } finally {
   byteMing = null;
   byteMi = null;
  }
  return strMing;
}
/**
  * 加密以byte[]明文输入,byte[]密文输出
  *
  * @param byteS
  * @return
  */
private byte[] getEncCode(byte[] byteS) {
  byte[] byteFina = null;
  Cipher cipher;
  try {
   cipher = Cipher.getInstance("DES");
   cipher.init(Cipher.ENCRYPT_MODE, key);
   byteFina = cipher.doFinal(byteS);
  } catch (Exception e) {
   e.printStackTrace();
  } finally {
   cipher = null;
  }
  return byteFina;
}
/**
  * 解密以byte[]密文输入,以byte[]明文输出
  *
  * @param byteD
  * @return
  */
private byte[] getDesCode(byte[] byteD) {
  Cipher cipher;
  byte[] byteFina = null;
  try {
   cipher = Cipher.getInstance("DES");
   cipher.init(Cipher.DECRYPT_MODE, key);
   byteFina = cipher.doFinal(byteD);
  } catch (Exception e) {
   e.printStackTrace();
  } finally {
   cipher = null;
  }
  return byteFina;
}
/**
  * 二行制转字符串
  *
  * @param b
  * @return
  */
public static String byte2hex(byte[] b) { // 一个字节的数,
  // 转成16进制字符串
  String hs = "";
  String stmp = "";
  for (int n = 0; n < b.length; n++) {
   // 整数转成十六进制表示
   stmp = (java.lang.Integer.toHexString(b[n] & 0XFF));
   if (stmp.length() == 1)
    hs = hs + "0" + stmp;
   else
    hs = hs + stmp;
  }
  return hs.toUpperCase(); // 转成大写
}
public static byte[] hex2byte(byte[] b) {
  if ((b.length % 2) != 0)
   throw new IllegalArgumentException("长度不是偶数");
  byte[] b2 = new byte;
  for (int n = 0; n < b.length; n += 2) {
   String item = new String(b, n, 2);
   // 两位一组,表示一个字节,把这样表示的16进制字符串,还原成一个进制字节
   b2[n / 2] = (byte) Integer.parseInt(item, 16);
  }
  return b2;
}
public static void main(String[] args) {
  System.out.println("hello");
  DesEncrypt des = new DesEncrypt();// 实例化一个对像
  des.getKey("00000000");// 生成密匙
  String strEnc = des.getEncString("12345678");// 加密字符串,返回String的密文
  System.out.println(strEnc);
  String strDes = des.getDesString(strEnc);// 把String 类型的密文解密
  System.out.println(strDes);
 
}
}

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