Question

我经常遇到NetBeans问题。之前我能够运行这个程序没问题，但现在，它在运行后告诉我这个

“线程中的异常”主“java.lang.RuntimeException：无法编译的源代码 - 无法找到符号符号：类Loop1 位置：类hw7 在hw7.main（hw7.java:72）“

import java.util.Scanner;
class forLoops {
void forLoop1(){
    Scanner in = new Scanner(System.in);
    int cnt = 2;

    System.out.print("Enter n:");
    int n = in.nextInt();

    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= i; j++){
            if (i == 1)
                System.out.print(1);
            else if (i > 1) {
                System.out.printf("%3d", cnt);
                cnt++;
            }
        }
        System.out.println();
    }
    }


void forLoop2(){
    Scanner in = new Scanner(System.in);

    System.out.print("Enter n:");
    int n = in.nextInt();

    for (int i = 1; i < n+1; i++) {
        int sum = 0;
        for (int j = 0; j < i; j++){
           System.out.printf("%3d", i+sum);
           sum = sum + n-(j+1);
        }
        System.out.println();
        }
    }

void forLoop3(){
    Scanner in = new Scanner(System.in);

    System.out.print("Enter n:");
    int n = in.nextInt();

    int x = 1;

    for (int i = 1; i < n+1; i++) {
        int sum = 0;
        for (int j = 0; j < i; j++){
           System.out.printf("%3d", i+sum);
           sum = sum + n-(j+1);
        }
        System.out.println();
        }
    }
}  
public class hw7 {
public static void main(String[] args) {
    Scanner in = new Scanner(System.in);

    forLoops myL1 = new forLoops();
    myL1.forLoop1();
    forLoops myL2 = new forLoops();
    myL2.forLoop2();
    Loops myL3 = new forLoops();
    myL3.forLoop3();
}

}

Answer 1

您没有正确地实例化该类。由于它的名称是forLoops，因此您需要执行以下操作：

forLoops myL1 = new forLoops();
myL1.forLoop1();
forLoops myL2 = new forLoops();
myL2.forLoop2();
forLoops myL3 = new forLoops();
myL3.forLoop3();

与问题无关，请注意，按照惯例，Java 中的类以大写字母开头。

Answer 2

这是第72行：Loop1 myL1 = new Loop1();

您正在使用名为Loop1的类，但尚未定义它。

为什么我的编译器告诉我有一个Uncompilable源代码？

2 个答案: