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所以我试图通过读取一个充满数据的文本文件来模拟一个非常基本的搜索引擎，然后让用户使用一些关键字搜索文件，然后返回包含该关键字的文本文件中包含的任何“网站”给用户。到目前为止，我的代码可以读取文本文件（据我所知），但是无论输入的关键字如何，控制台几乎总是表明找不到任何结果（文本文件不包含关键字。谢谢每个人。

这是适当的代码：

package myquery;

import java.util.Scanner;
import java.util.*;
import java.io.*;

public class MyQuery{

public static void main(String[] args){

    Hashtable<String, ArrayList<String> > hash = new Hashtable<String, ArrayList<String> >();
    Scanner input = new Scanner(System.in);
    System.out.println("Here is where your .txt file(s) should be located for this program to work properly:");
    System.out.println(new java.io.File("").getAbsolutePath());
    System.out.println("\nEnter the filename that you want to Search values for. For example \"MyQuery.txt\"");
    BufferedReader reader = null;

    try{
        reader = new BufferedReader(new FileReader(input.nextLine()));
        System.out.println("The file was found :) Here are the contents:");

        while(reader.ready())
        {
            String currentline = reader.readLine();
            String[] result = currentline.split("\\s");
            for(int i = 0; i < result.length; i++)
            {
                if(!hash.containsKey(result[i]))
                {
                    ArrayList<String> temp = new ArrayList<String>(1);
                    temp.add(currentline);
                    hash.put(result[i], temp);
                }
                else
                {
                    ArrayList<String> temp = (ArrayList<String>)hash.get(result[i]);//
                    temp.add(currentline);
                }
            }
        }
    }

    catch(Exception e)
    {
        System.out.println("Your file was not found unfortunately. Please try again.");
        System.exit(1);
    }

    System.out.println(hash);
    do
    {
        System.out.println("Enter a key to search for the value it is associated with.\n");
        System.out.println(hash.get(input.nextLine()));
        System.out.println("\nWant to try again? If so, press return and then follow the prompt. Type \"-1\" to quit");
    }
    while(!input.nextLine().equals("-1"));
    try
    {
        reader.close();
    }
    catch(Exception e)
    {
        System.out.println(e);
        System.exit(1);
    }
}
}

以及文本文件中一行的示例：

www.Mets.com, "The New York Mets", baseball, team, NY

这是程序应如何响应的示例：

Enter a key to search for the value it is associated with.

Mets
www.Mets.com The New York Mets

Want to try again? If so, press return and then follow the prompt. Type "-1" to quit

但这是我得到的：

Enter a key to search for the value it is associated with:

Mets
null

Want to try again? If so, press return and then follow the prompt. Type "-1" to quit

虽然。如果我输入一个与除第一个/最后一个单词之外的任何单词匹配的单词，它就会起作用。

例如

Enter a key to search for the value it is associated with:

New
[www.Mets.com, "The New York Mets", baseball, team, NY, www.nytimes.com, "The New York Times", news]

Want to try again? If so, press return and then follow the prompt. Type "-1" to quit
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