首页 > 代码库 > SafeNet推出行业首款白盒密码软件保护解决方案

SafeNet推出行业首款白盒密码软件保护解决方案

下面是基于KWIC 的关键字匹配算法(管道+过滤器模式下实现)

关键部分的管道+过滤器 软件体系下的实现, 在很多的关键字搜索平台都使用了这一 循环移位+排序输出的 关键字匹配算法:

具体需求如下:

1、使用管道-过滤器风格:
每个过滤器处理数据,然后将结果送至下一个过滤器,。要有数据传入,过滤器即开始工作。过滤器之间的数据共享被严格限制在管道传输
四个过滤器:
输入(Input filter):
从数据源读取输入文件,解析格式,将行写入输出管道
移位(CircularShifter filter):循环移位
排序(Alphabetizer filter):
输出(Output filter)
管道:
  in_cs pipe
  cs_al pipe
  al_ou pile

例如:


代码如下:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace KWIC
{
    /// <summary>
    /// 管道类
    /// </summary>
    public class Pipe
    {
      List<string> word;
      public List<string> read()
        {
            return word;
        }
      public void write(List<string> word)
        { this.word = word; }
    }

    /// <summary>
    /// 管道之间的过滤器接口
    /// </summary>
    public abstract class Filter
    {
      
        public virtual void Transform()
        { }
    }

    /// <summary>
    /// 继承并实现实现管道接口
    /// </summary>
    public class InputFilter : Filter
    {

        public Pipe outPipe;
        public List<string> word;
        public InputFilter(List<string> word, Pipe outPipe)
        {
            this.word = word;
            this.outPipe = outPipe;
        }
        public void Transform()
        {
            outPipe.write(word);
        }
    }

    /// <summary>
    /// 继承并实现过滤器接口
    /// </summary>
    public class CircleShiftFilter : Filter
    {
        public Pipe inputPipe;
        public Pipe outPipe;
        public CircleShiftFilter(Pipe inputPipe, Pipe outPipe)
        {
            this.inputPipe = inputPipe;
            this.outPipe = outPipe;
        }
        /// <summary>
        /// 关键的循环移位函数
        /// </summary>
        public virtual void Transform()
        {
            List<string> word = inputPipe.read();

            /////////////////////////////////////////////// 补充代码,将WORD数组中字符串循环移位////////////////////////////////////////////////////////

            List<string> turned_words = new List<string>();

            // 获得每一行字符串数据
            foreach (string line in word)
            { 
                // 拆分一句话
                string[] words = line.Split(' ');

                // 获取单词数
                ulong word_number = (ulong)words.LongLength;

                // 临时存储中间排序好的串
                List<string> tmp_words = new List<string>();
                
                tmp_words.Clear();

                tmp_words.Add(line);

                string tmp_line = "";

                for (ulong i = 0; i < word_number - 1; i++)
                {
                    // 获取上一行串
                    tmp_line = tmp_words[tmp_words.Count - 1];

                    // 获取上一行串的最后一个单词
                    string last_word = tmp_line.Split(' ')[word_number -1];

                    // 获取上一行串的除了最后一个单词之外的所有单词
                    string left_words = tmp_line.Substring(0, (tmp_line.Length -last_word.Length-1 ));

                    tmp_words.Add(last_word +" "+ left_words ); 
                }

                // 移除原有的串
                tmp_words.RemoveAt(0);

                // 将一句移位的串加到临时的list集合
                turned_words.AddRange(tmp_words);

            }

            // 将所有移位的串加到原来list集合
            word.AddRange(turned_words);

            /////////////////////////////////////
            outPipe.write(word); 
        
        }
    }

    /// <summary>
    /// 实现的排序过滤器类
    /// </summary>
    public class AlphaFilter : Filter
    {
        public Pipe inputPipe;
        public Pipe outPipe;
        public AlphaFilter(Pipe inputPipe, Pipe outPipe)
        {
            this.inputPipe = inputPipe;
            this.outPipe = outPipe;
        }

        /// <summary>
        /// 排序输出函数
        /// </summary>
        public void Transform()
        {
            List<string> word = inputPipe.read();

            ////////////////////////////////////// 补充代码,将word数组中单词排序输出/////////////////////////////////////////////////
            word.Sort();

            outPipe.write(word); 
       
        }
    }

    /// <summary>
    /// 实现输出过滤器接口类
    /// </summary>
    public class OutputFilter : Filter
    {
        public Pipe inputPipe;
        public Pipe outPipe;
        public OutputFilter(Pipe inputPipe, Pipe outPipe)
        {
            this.inputPipe = inputPipe; this.outPipe = outPipe;
            
        }
        public  void Transform()
        {
            List<string> word = inputPipe.read();
            outPipe.write(word); 
        }
    }

    /// <summary>
    /// 程序的整体运行框架
    /// </summary>
    public class KWIC_System
    {

        Pipe in_cs; // create three objects of Pipe
        Pipe cs_al; // and one object of type
        Pipe al_ou; // FileInputStream
        Pipe ou_ui; // FileInputStream
        InputFilter inputFilter;
        CircleShiftFilter shifter;
        AlphaFilter alpha;
        OutputFilter output; // output to screen
      public   KWIC_System()
        {
            in_cs = new Pipe(); // create three objects of Pipe
            cs_al = new Pipe(); // and one object of type
            al_ou = new Pipe(); // FileInputStream
            ou_ui = new Pipe(); // FileInputStream

            List<string> word = new List<string>();
	    word.Add(Regex.Replace("I love you".Trim(), @"\s+", " ")); //正则会获取到所有类型的空格(比如制表符,新行等等),然后将其替换为一个空格  
            word.Add(Regex.Replace("me too".Trim(), @"\s+", " "));  
            word.Add(Regex.Replace("do you know".Trim(), @"\s+", " "));  


            inputFilter = new InputFilter(word, in_cs);
            shifter = new CircleShiftFilter(in_cs, cs_al);
            alpha = new AlphaFilter(cs_al, al_ou);
            output = new OutputFilter(al_ou,ou_ui); // output to screen
        }
        public List<string > GetResult()
        {
            inputFilter.Transform();
            shifter.Transform();
            alpha.Transform();
            output.Transform();

            return ou_ui.read();
        }


    }

}

(备注:如果想换行这里想换行输出,需要在结尾输出的每一行结尾加‘\r\n’)

在广泛的搜索技术中,其实这个关键字匹配算法应用范围很广,比如我们常见的Baidu和Google的搜索关键字 提示功能。