Java实现加密与解密

 

工作中遇到,备份下来,留以后使用.

 

 

 

package com.ysj.util;
import java.io.*;

/**
 * 加密解密
 * @author Administrator
 */

public class Encipher{
	// 加密
    public static String EncodePasswd(String strPasswd){
        String strEncodePasswd = new String("");
        int i;
        int n;
        char code;
        String des = new String();
        String strKey = new String();
        if((strPasswd == null) || strPasswd.length() == 0){
            strEncodePasswd = "";
            return strEncodePasswd;
        }
        strKey = EncipherConst.m_strKey1 + EncipherConst.m_strKey2 + EncipherConst.m_strKey3 + EncipherConst.m_strKey4 + EncipherConst.m_strKey5 + EncipherConst.m_strKey6;
        while(strPasswd.length() < 8){
            strPasswd = strPasswd + (char)1;
        }
        des = "";
        for(n = 0; n <= strPasswd.length() - 1; n++){
            while(true){
                code = (char)Math.rint(Math.random() * 100);
                while((code > 0) && (((code ^ strPasswd.charAt(n)) < 0) || ((code ^ strPasswd.charAt(n)) > 90))){
                    code = (char)((int)code - 1);
                }
                char mid = 0;
                int flag;
                flag = code ^ strPasswd.charAt(n);
                if(flag > 93){
                    mid = 0;
                }else{
                    mid = strKey.charAt(flag);
                }
                if((code > 35) & (code < 122) & (code != 124) & (code != 39) & (code != 44) & (mid != 124) & (mid != 39) & (mid != 44)){
                    break;
                }
                //确保生成的字符是可见字符并且在SQL语句中有效
            }
            char temp = 0;
            temp = strKey.charAt(code ^ strPasswd.charAt(n));
            des = des + (char)code + temp;
        }
        strEncodePasswd = des;
        return strEncodePasswd;
    }
    // 解密
    public static String DecodePasswd(String varCode){
        int n;
        String des = new String();
        String strKey = new String();
        if((varCode == null) || (varCode.length() == 0)){
            return "";
        }
        strKey = EncipherConst.m_strKey1 + EncipherConst.m_strKey2 + EncipherConst.m_strKey3 + EncipherConst.m_strKey4 + EncipherConst.m_strKey5 + EncipherConst.m_strKey6;
        if(varCode.length() % 2 == 1){
            varCode = varCode + "?";
        }
        des = "";
        for(n = 0; n <= varCode.length() / 2 - 1; n++){
            char b;
            b = varCode.charAt(n * 2);
            int a;
            a = (int)strKey.indexOf(varCode.charAt(n * 2 + 1));
            des = des + (char)((int)b ^ a);
        }
        n = des.indexOf(1);
        if(n > 0){
            return des.substring(0, n);
        } else{
            return des;
        }
    }
    
    static class EncipherConst{
        public final static String m_strKey1 = "zxcvbnm,./asdfg";
        public final static String m_strKeya = "cjk;";
        public final static String m_strKey2 = "hjkl;'qwertyuiop";
        public final static String m_strKeyb = "cai2";
        public final static String m_strKey3 = "[]\\1234567890-";
        public final static String m_strKeyc = "%^@#";
        public final static String m_strKey4 = "=` ZXCVBNM<>?:LKJ";
        public final static String m_strKeyd = "*(N";
        public final static String m_strKey5 = "HGFDSAQWERTYUI";
        public final static String m_strKeye = "%^HJ";
        public final static String m_strKey6 = "OP{}|+_)(*&^%$#@!~";
    }
    // 测试
    public static void  main(String[] args) throws Exception{
    	String pas = "123" ;
    	String encodePas = EncodePasswd(pas);
    	System.out.println(encodePas);
    	String decodePas = DecodePasswd(encodePas);
        System.out.println(decodePas);
    }
}