java - 尝试比较数组时出现空指针异常

因此，当我调用firstCompare方法时，在此行if(numbers1[i].compareTo(numbers2[i]) == 0){上得到一个NullPointerException

但是，打印阵列显示它们已满。请帮忙！

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;

public class Fugitive {
    public static int counter = 0;
    public static int flag;

    static String[] numbers1 = new String[35];
    static String[] numbers2 = new String[35];
    static String[] numbers3 = new String[35];

    public static void main(String[] args) throws IOException {
        loadNumbers();
        firstCompare();



    }
    public static void loadNumbers() throws IOException {
        String print;
        BufferedReader in = new BufferedReader(new FileReader("creditCards1.txt"));
        BufferedReader in2 = new BufferedReader(new FileReader("creditCards2.txt"));
        BufferedReader in3 = new BufferedReader(new FileReader("creditCards3.txt"));


        for (int i = 0; i < 34; i++){
                //read in the data
                numbers1[i] = in.readLine();
                numbers2[i] = in2.readLine();
                numbers3[i] = in3.readLine();
                counter++;
            }
         in.close();
    }

    public static void firstCompare() {
        boolean found = false;
        for (int i = 0; i < 34; i++){
            if(numbers1[i].compareTo(numbers2[i]) == 0){
                flag = i;
                found = true;
                System.out.println(flag);
            }
        }
        if (!found){
            System.out.println("No matches");
    }
    }

}

最佳答案

您应在循环中用name.length替换数字100和10

关于java - 尝试比较数组时出现空指针异常，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/32322305/