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);
?
}
}
