java - 检查一个字符串是否相等或另一个字符串的子字符串

Question

我正在尝试使用以下代码检查一个字符串是否与另一个字符串相同，或者它是否是其中的一部分:

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.util.Scanner;


public class Comparison {

    static void compare() throws FileNotFoundException {

        Scanner queries = new Scanner(new FileReader("./out.txt"));
        Scanner folks = new Scanner(new FileReader("./tal.txt"));
        int index1 = 0;
        while ( queries.hasNextLine() ){
            String check = queries.next();

            while (folks.hasNextLine()) {
                String toCheck = folks.next();
                index1 = toCheck.indexOf(check);
            }//while
        }//while

        System.out.println("Result: "+ index1);
    }
}

但我收到以下错误:

线程“main”中的异常 java.util.NoSuchElementException
在 java.util.Scanner.throwFor(Scanner.java:838)
在 java.util.Scanner.next(Scanner.java:1347)
在 results.Comparison.compare(Comparison.java:28)
在 results.Main.main(Main.java:42)

问题是什么？我怎样才能让它工作？

Answer 1

folks的初始化需要在外循环内，例如:

        Scanner queries = new Scanner(new FileReader("./out.txt"));
        int index1 = 0;
        while ( queries.hasNextLine() ){
            String check = queries.next();
            Reader r = new FileReader("./tal.txt");
            try {
                Scanner folks = new Scanner(r);
                while (folks.hasNextLine()) {
                    String toCheck = folks.next();
                    index1 = toCheck.indexOf(check);
                    if (index1 >= 0) {
                        // Do something with index1 here?
                    }
                }//while
            } finally {
                r.close();
            }
        }//while