java - 为什么线程“main”java.util.NoSuchElementException中出现此错误异常：

问题描述

我一直被这个错误困住，任何人都可以解决这个问题吗？我不断收到错误消息。我认为这是一个简单的修复，但我无法弄清楚。我已经修复了一段时间，我不知道在哪里。谢谢你的帮助。

import java.util.Scanner;

public class Menu {
    boolean exit;
    public static void main(String[] args){
        
        Menu menu = new Menu();
        menu.runMenu();
   
    }
    
    public void runMenu(){
        printHeader();
        while(!exit){
            printMenu();
            int choice = getInput();
            performAction(choice);
        }
    }
    
    private void printHeader(){
        System.out.println("+----------------------------+");
        System.out.println("|     Area Plane of Shape    |");
        System.out.println("+----------------------------+");
    }
    
    private void printMenu(){
        System.out.println(" ");
        System.out.println("Please make selection: ");
        System.out.println(" ");
        System.out.println("1) Area of the Square");
        System.out.println("2) Area of the Rectangle");
        System.out.println("3) Area of the Triangle");
        System.out.println("4) Area of the Circle");
        System.out.println("0) Exit");
    }

    private int getInput(){
        Scanner input = new Scanner(System.in);
        int choice = -1;
        do{
            System.out.println(" ");
            System.out.println("Enter your choice: ");
            try {    
                choice = Integer.parseInt(input.nextLine());
            } catch(NumberFormatException e){
                System.out.println("Invalid Selection. Please try again.");
            }
        }while(choice < 0 || choice > 4);     
        return choice;
        //return 1;
        }
         
    private void performAction(int choice){
        switch(choice){
            case 0:
                exit = true;
                System.out.println("Thank you for using my application.");
                break;
            case 1:
                areaofSquare();
                break;
            case 2:
                areaofRectangle();
                break;
            case 3:
                areaofTriangle();
                break;
            case 4:
                areaofCircle();
                break;
            default:
                System.out.println("Invalid");
        }
    }
  
    private void areaofSquare(){
        System.out.println("+----------------------------+");
        System.out.println("|   **Area of the Square**   |");
        System.out.println("+----------------------------+");
        System.out.println(" ");
        try (Scanner scanner = new Scanner(System.in)) {
            System.out.println("Enter Side of Square: ");
            // Storing the captured value in a variable
            double side = scanner.nextDouble();
            // Area of Square = side*side
            double area = side * side;
            System.out.println("Area of Square is: " + area);
        }    
    }
    
    private void areaofRectangle(){
        System.out.println("+----------------------------+");
        System.out.println("|  **Area of the Rectangle** |");
        System.out.println("+----------------------------+");
        System.out.println(" ");
         try (Scanner scanner = new Scanner(System.in)) {
            System.out.println("Enter the length of Rectangle:");
            double length = scanner.nextDouble();
            System.out.println("Enter the width of Rectangle:");
            double width = scanner.nextDouble();
            // Area = length*width;
            double area = length * width;
            System.out.println("Area of Rectangle is: " + area);
            
         }
    }
    
    private void areaofTriangle(){
        System.out.println("+----------------------------+");
        System.out.println("|  **Area of the Triangle**  |");
        System.out.println("+----------------------------+");
        System.out.println(" ");
         try (Scanner scanner = new Scanner(System.in)) {
            System.out.println("Enter the width of the Triangle:");
            double base = scanner.nextDouble();

            System.out.println("Enter the height of the Triangle:");
            double height = scanner.nextDouble();

            // Area = (width*height)/2
            double area = (base * height) / 2;
            System.out.println("Area of Triangle is: " + area);
            
         }
    }
    
    private void areaofCircle(){
        System.out.println("+----------------------------+");
        System.out.println("|   **Area of the Circle**   |");
        System.out.println("+----------------------------+");
        System.out.println(" ");
        try(Scanner scanner = new Scanner(System.in)) {
        System.out.println("Enter the radius:");
         double r= scanner.nextDouble();
         double  area=(22*r*r)/7 ;
         System.out.println("Area of Circle is: " + area);
         
        }
    }
}

我已经研究了错误报告和 Java 文档，并找到了具有类似问题的报告。请帮忙。

我收到这个错误

Exception in thread "main" java.util.NoSuchElementException: No line found
    at java.base/java.util.Scanner.nextLine(Scanner.java:1651)
    at Menu.getInput(Menu.java:50)
    at Menu.runMenu(Menu.java:20)
    at Menu.main(Menu.java:9)
Command execution failed.

标签： java

java - 为什么线程“main”java.util.NoSuchElementException中出现此错误异常：

问题描述

解决方案

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