java des加密与解密-优快云博客

本文介绍了一个Java实现的DES加密解密工具类，该工具类提供了生成密钥、加密和解密等功能，并通过示例展示了如何使用这些功能。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

package com.suning.ebuy.hyj.treaty.util;
import java.security.Key;
import java.security.SecureRandom;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
   
public class DesUtil {

	Key key;
	public DesUtil(String str) {
	    setKey(str);//生成密匙
	}
	public DesUtil() {
	    setKey("siyue_qi");
	}
	/**
	   * 根据参数生成KEY
	   */
	public void setKey(String strKey) {
	      try {
	        KeyGenerator _generator = KeyGenerator.getInstance("DES");
	        _generator.init(new SecureRandom(strKey.getBytes()));
	        this.key = _generator.generateKey();
	        _generator = null;
	      } catch (Exception e) {
	        throw new RuntimeException(
	            "Error initializing SqlMap class. Cause: " + e);
	      }
	}
	/**
	   * 加密String明文输入,String密文输出
	   */
	public  String getEncString(String strMing) {
	      byte[] byteMi = null;
	      byte[] byteMing = null;
	      String strMi = "";
		BASE64Encoder base64en = new BASE64Encoder();
	      try {
	        byteMing = strMing.getBytes("UTF8");
	        byteMi = this.getEncCode(byteMing);
	        strMi = base64en.encode(byteMi);
	      } catch (Exception e) {
	        throw new RuntimeException(
	            "Error initializing SqlMap class. Cause: " + e);
	      } finally {
	        base64en = null;
	        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) {
	      BASE64Decoder base64De = new BASE64Decoder();
	      byte[] byteMing = null;
	      byte[] byteMi = null;
	      String strMing = "";
	      try {
	        byteMi = base64De.decodeBuffer(strMi);
	        byteMing = this.getDesCode(byteMi);
	        strMing = new String(byteMing, "UTF8");
	      } catch (Exception e) {
	        throw new RuntimeException(
	            "Error initializing SqlMap class. Cause: " + e);
	      } finally {
	        base64De = null;
	        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) {
	        throw new RuntimeException(
	            "Error initializing SqlMap class. Cause: " + e);
	      } 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) {
	        throw new RuntimeException(
	            "Error initializing SqlMap class. Cause: " + e);
	      } finally {
	        cipher = null;
	      }
	      return byteFina;
	}
	public static void main(String args[]) {
		DesUtil des = new DesUtil();
	      // 设置密钥
	      //des.setKey("12345678");
	      String str1 = "0";
	      //DES加密
	      String str2 = des.getEncString(str1);
	      String deStr = des.getDesString(str2);
	      System.out.println("密文:" + str2);
	      //DES解密
	      System.out.println("明文:" + deStr);
	}
}