Java简单计算器将无法编译

Question

我是编程的新手，我做了一个简单的计算器，无法弄清楚它为什么不能编译。所有帮助赞赏。

import java.util.Scanner;

public class Cal
{
  Scanner sc = new Scanner(System.in);   

第一个号码

public static double getInput1()
  {
   while(true)
   {
     try
     {
       double num1 = sc.nextDouble();
       return num1;
     }
     catch (Exception e)
     {
       sc.next();
       System.out.print("Error, please try again:");
     }
   }
  }

操作

  public static int getInput2()
  {
     while(true)
     {
       try
       {
         int operation = sc.nextInt();
         return operation;
      }
       catch (Exception e)
       {
         sc.next();
         System.out.print("Error, please try again:");
       }
      }
   }

第二个号码

  public static double getInput3()
  {
   while(true)
   {
     try
     {
       double num2 = sc.nextDouble();
       return num2;
     }
     catch (Exception e)
     {
       sc.next();
       System.out.print("Error, please try again:");
     }
   }
  }

如果计算器返回true，则该方法应该重复计算器

  public static boolean continue()
  {
    while(true)
    {
      try
      {
        boolean answer = sc.nextBoolean();
        return answer;
      }
      catch (Exception e)
      {
        sc.next();
        System.out.print("Error, please try again:");
      }
    }
  }

主要方法

   public static void main(String[] args)
   {
    System.out.println("Welcome to Simple Calculator Version 1.1");
    do
    {
      System.out.print("Enter the first number :");
      double num1 = getInput1();
      System.out.print("Enter 1 for +, 2 for -, 3 for *, 4 for /, :");
      int operation = getInput2();
      System.out.print("Enter the second number :");
      double num2 = getInput3();
      switch (operation)
      {
        case 1:
          System.out.println("The answer is " + (num1 + num2));
          break;
        case 2:
          System.out.println("The answer is " + (num1 - num2));
          break;
        case 3:
          System.out.println("The answer is " + (num1 * num2));
          break;
        case 4:
          System.out.println("The answer is " + (num1 / num2));
          break;
      }
      System.out.print("Do you want to continue true or false :");
      boolean reply = continue();
    }
    while(reply);
    System.out.println("Thankyou for using Simple Calculator 1.1, have a nice day. ");
  }
}

以下是错误消息

    Cal.java:54: error: <identifier> expected 
  public static boolean continue() 
                       ^ 
Cal.java:54: error: illegal start of type 
  public static boolean continue() 
                                ^ 
Cal.java:54: error: <identifier> expected 
  public static boolean continue() 
                                 ^ 
Cal.java:54: error: ';' expected 
  public static boolean continue() 
                                  ^ 
Cal.java:56: error: illegal start of type 
    while(true) 
    ^ 
Cal.java:56: error: <identifier> expected 
    while(true) 
         ^ 
Cal.java:56: error: ';' expected 
    while(true) 
          ^ 
Cal.java:56: error: illegal start of type 
    while(true) 
              ^ 
Cal.java:56: error: <identifier> expected 
    while(true) 
               ^ 
Cal.java:57: error: ';' expected 
    { 
     ^ 
Cal.java:63: error: illegal start of type 
      catch (Exception e) 
      ^ 
Cal.java:69: error: class, interface, or enum expected 
  } 
  ^ 
Cal.java:70: error: class, interface, or enum expected 
  public static void main(String[] args) 
                ^ 
Cal.java:73: error: class, interface, or enum expected 
    do 
    ^ 
Cal.java:76: error: class, interface, or enum expected 
      double num1 = getInput1(); 
      ^ 
Cal.java:77: error: class, interface, or enum expected 
      System.out.print("Enter 1 for +, 2 for -, 3 for *, 4 for /, :"); 
      ^ 
Cal.java:78: error: class, interface, or enum expected 
      int operation = getInput2(); 
      ^ 
Cal.java:79: error: class, interface, or enum expected 
      System.out.print("Enter the second number :"); 
      ^ 
Cal.java:80: error: class, interface, or enum expected 
      double num2 = getInput3(); 
      ^ 
Cal.java:81: error: class, interface, or enum expected 
      switch (operation) 
      ^ 
Cal.java:85: error: class, interface, or enum expected 
          break; 
          ^ 
Cal.java:86: error: class, interface, or enum expected 
        case 2: 
        ^ 
Cal.java:88: error: class, interface, or enum expected 
          break; 
          ^ 
Cal.java:89: error: class, interface, or enum expected 
        case 3: 
        ^ 
Cal.java:91: error: class, interface, or enum expected 
          break; 
          ^ 
Cal.java:92: error: class, interface, or enum expected 
        case 4: 
        ^ 
Cal.java:94: error: class, interface, or enum expected 
          break; 
          ^ 
Cal.java:95: error: class, interface, or enum expected 
      } 
      ^ 
Cal.java:97: error: class, interface, or enum expected boolean reply = continue(); 
      ^ 
Cal.java:98: error: class, interface, or enum expected 
    } 
    ^ 
Cal.java:100: error: class, interface, or enum expected 
    System.out.println("Thankyou for using Simple Calculator 1.1, have a nice  day. "); 
    ^ 
Cal.java:101: error: class, interface, or enum expected 
  } 
  ^ 
32 errors