На этот вопрос уже есть ответ:

Извините, если это странный вопрос, но я только что запустил ООП и столкнулся с этой проблемой для простой математической программы, управляемой меню, которую я должен был создать. Я очистил все ошибки, которые дал мне компилятор, но теперь он дает мне около 14 свежих ошибок, большинство из которых описаны как «не удается найти символ». Вот мой код:

import java.util.Scanner;


public class MathMenu
{


//MENU METHOD
private static void menu(String args[])
{
int choice;

System.out.printf("Enter '1' to add");
System.out.printf("Enter '2' to subtract");
System.out.printf("Enter '3' to exit");

System.out.printf("\nPlease enter your choice: ");


choice=input.nextInt();

if (choice==1)
sum(n,m);

if (choice==2)
dif(n,m);

else if(choice==3)
return;

}



//SUM
private static int sum(int a, int b)
{
return n+m;
}


//DIFFERENCE 
private static int dif(int a, int b)
{
if(n<m)
return m-n;

else
return n-m;
}





public static void main(String args[])
{


int n=15;
int m=8;

Scanner input = new Scanner(System.in);

menu();

}


}

И вот новый вывод компилятора:

Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation.  All rights reserved.

C:\Users\Shahraiz Tabassam>cd c:\java\bin

c:\java\bin>javac MathMenu.java
MathMenu.java:7: error: no suitable constructor found for Scanner()
private static Scanner input = new Scanner();
                               ^
    constructor Scanner.Scanner(ReadableByteChannel,String) is not applicable
      (actual and formal argument lists differ in length)
    constructor Scanner.Scanner(ReadableByteChannel) is not applicable
      (actual and formal argument lists differ in length)
    constructor Scanner.Scanner(String) is not applicable
      (actual and formal argument lists differ in length)
    constructor Scanner.Scanner(Path,Charset) is not applicable
      (actual and formal argument lists differ in length)
    constructor Scanner.Scanner(Path,String) is not applicable
      (actual and formal argument lists differ in length)
    constructor Scanner.Scanner(Path) is not applicable
      (actual and formal argument lists differ in length)
    constructor Scanner.Scanner(File,CharsetDecoder) is not applicable
      (actual and formal argument lists differ in length)
    constructor Scanner.Scanner(File,String) is not applicable
      (actual and formal argument lists differ in length)
    constructor Scanner.Scanner(File) is not applicable
      (actual and formal argument lists differ in length)
    constructor Scanner.Scanner(InputStream,String) is not applicable
      (actual and formal argument lists differ in length)
    constructor Scanner.Scanner(InputStream) is not applicable
      (actual and formal argument lists differ in length)
    constructor Scanner.Scanner(Readable) is not applicable
      (actual and formal argument lists differ in length)
    constructor Scanner.Scanner(Readable,Pattern) is not applicable
      (actual and formal argument lists differ in length)
MathMenu.java:64: error: method menu in class MathMenu cannot be applied to give
n types;
menu();
^
  required: String[]
  found: no arguments
  reason: actual and formal argument lists differ in length
2 errors

c:\java\bin>