我正在尝试让我的程序使用类，但输出错误显示：
Line: 32
cannot find symbol
symbol: method add()
location: class maincalculator.MainCalculator
Line: 35
cannot find symbol
symbol: method subtraction()
location: class maincalculator.MainCalculator
Line: 38
cannot find symbol
symbol: method division()
location: class maincalculator.MainCalculator
Line: 41
cannot find symbol
symbol: method multiply()
location: class maincalculator.MainCalculator
我想让这段代码工作，所以我可以完成我的任务，但我的任务是为不同的原始方法创建类。这是我当前的编译错误。
我的代码：
package maincalculator;
//Imports the scanner that I will be using.
import java.util.Scanner;
/**
*
* @author alex
*/
public class MainCalculator {
//Public static void for the class.
public static void main(String[] args) {
//Welcome print at the start of application.
System.out.println("Welcome to the Calculator V1.O");
//Blank line seperator.
System.out.println("");
System.out.println("What would you like to do today?");
System.out.println("");
//The options that will be shown to the program user in the console.
//Option List for the program.
System.out.println("1. Add");
System.out.println("2. Subtract");
System.out.println("3. Divide");
System.out.println("4. Multiply");
//Scans for the selected option.
//Creates a new scanner.
Scanner scan = new Scanner(System.in);
//Checks if the next integer is selected.
//Variables set to load the functions of each calculator.
//Scans the integer choices.
int choice = scan.nextInt();
switch (choice) {
case 1:
add();
break;
case 2:
subtraction();
break;
case 3:
division();
break;
case 4:
multiply();
break;
default:
//Print this line if 1-4 are not selected.
System.out.println("Option Unavailable");
break;
}
}
class add {
public void addcode (){
//Input a new scanner.
Scanner input = new Scanner( System.in );
//Collects the data from number1 and number2.
int number1;
int number2;
int sum;
//Menu name
System.out.println( "Add" );
//Creates the message for the first number.
System.out.print( "Enter your first number: " );
//Creates the message for the second nmber.
number1 = input.nextInt(); //Defines number1
System.out.print( "Enter your second number: " );
number2 = input.nextInt(); //Defines number2
//Use addition symbol between the two numbers.
sum = number1 + number2;
System.out.printf( "Sum equals %d\n", sum);
}
}
class sub {
public void subcode (){
Scanner input = new Scanner( System.in );
int number1;
int number2;
int sum;
System.out.println( "Subtraction" );
System.out.print( "Enter your first number: " );
number1 = input.nextInt(); //Defines number1
System.out.print( "Enter your second number: " );
number2 = input.nextInt(); //Defines number2
sum = number1 - number2;
System.out.printf( "Sum equals %d\n", sum);
}
}
class div {
public void divcode (){
Scanner input = new Scanner( System.in );
int number1;
int number2;
int sum;
System.out.println( "Division" );
System.out.print( "Enter your first number: " );
number1 = input.nextInt(); //Defines number1
System.out.print( "Enter your second number: " );
number2 = input.nextInt(); //Defines number2
sum = number1 / number2;
System.out.printf( "Sum equals %d\n", sum);
}
}
class multi {
public void multicode (){
//Multiplication
//New scanner.
Scanner input = new Scanner( System.in );
//Int number from below.
int number1;
int number2;
//The sum answer displayed.
int sum;
System.out.println( "Multiply" );
System.out.print( "Enter your first number: " );
number1 = input.nextInt(); //Defines number1
System.out.print( "Enter your second number: " );
number2 = input.nextInt(); //Defines number2
sum = number1 * number2;
System.out.printf( "Sum equals %d\n", sum);
}
}
}
答案 0 :(得分：1)
试试这个!!!!!!
package maincalculator;
//Imports the scanner that I will be using.
import java.util.Scanner;
/**
*
* @author alex
*/
public class MainCalculator {
//Public static void for the class.
public static void main(String[] args) {
//Welcome print at the start of application.
System.out.println("Welcome to the Calculator V1.O");
//Blank line seperator.
System.out.println("");
System.out.println("What would you like to do today?");
System.out.println("");
//The options that will be shown to the program user in the console.
//Option List for the program.
System.out.println("1. Add");
System.out.println("2. Subtract");
System.out.println("3. Divide");
System.out.println("4. Multiply");
//Scans for the selected option.
//Creates a new scanner.
Scanner scan = new Scanner(System.in);
//Checks if the next integer is selected.
//Variables set to load the functions of each calculator.
//Scans the integer choices.
int choice = scan.nextInt();
switch (choice) {
case 1:
Add.addcode();
break;
case 2:
Sub.subcode();
break;
case 3:
Div.divcode();
break;
case 4:
Multi.multicode();
break;
default:
//Print this line if 1-4 are not selected.
System.out.println("Option Unavailable");
break;
}
}
}
class Add {
public static void addcode (){
//Input a new scanner.
Scanner input = new Scanner( System.in );
//Collects the data from number1 and number2.
int number1;
int number2;
int sum;
//Menu name
System.out.println( "Add" );
//Creates the message for the first number.
System.out.print( "Enter your first number: " );
//Creates the message for the second nmber.
number1 = input.nextInt(); //Defines number1
System.out.print( "Enter your second number: " );
number2 = input.nextInt(); //Defines number2
//Use addition symbol between the two numbers.
sum = number1 + number2;
System.out.printf( "Sum equals %d\n", sum);
}
}
class Sub {
public static void subcode (){
Scanner input = new Scanner( System.in );
int number1;
int number2;
int sum;
System.out.println( "Subtraction" );
System.out.print( "Enter your first number: " );
number1 = input.nextInt(); //Defines number1
System.out.print( "Enter your second number: " );
number2 = input.nextInt(); //Defines number2
sum = number1 - number2;
System.out.printf( "Sum equals %d\n", sum);
}
}
class Div {
public static void divcode (){
Scanner input = new Scanner( System.in );
int number1;
int number2;
int sum;
System.out.println( "Division" );
System.out.print( "Enter your first number: " );
number1 = input.nextInt(); //Defines number1
System.out.print( "Enter your second number: " );
number2 = input.nextInt(); //Defines number2
sum = number1 / number2;
System.out.printf( "Sum equals %d\n", sum);
}
}
class Multi {
public static void multicode (){
//Multiplication
//New scanner.
Scanner input = new Scanner( System.in );
//Int number from below.
int number1;
int number2;
//The sum answer displayed.
int sum;
System.out.println( "Multiply" );
System.out.print( "Enter your first number: " );
number1 = input.nextInt(); //Defines number1
System.out.print( "Enter your second number: " );
number2 = input.nextInt(); //Defines number2
sum = number1 * number2;
System.out.printf( "Sum equals %d\n", sum);
}
}
答案 1 :(得分：0)
因为没有声明add（）方法..
删除您的类添加，然后将此方法添加到类MainCalculator
public void add(){
//Input a new scanner.
Scanner input = new Scanner( System.in );
//Collects the data from number1 and number2.
int number1;
int number2;
int sum;
//Menu name
System.out.println( "Add" );
//Creates the message for the first number.
System.out.print( "Enter your first number: " );
//Creates the message for the second nmber.
number1 = input.nextInt(); //Defines number1
System.out.print( "Enter your second number: " );
number2 = input.nextInt(); //Defines number2
//Use addition symbol between the two numbers.
sum = number1 + number2;
System.out.printf( "Sum equals %d\n", sum);
}
同样适用于减法，乘法等其他方法
编辑：
public class Calculator
{
private int solution;
private int x;
private int y;
public calculator(int x,int y)
{
this.x=x;
this.y=y;
}
public int add()
{
return x + y;
}
public int subtract()
{
return x - y;
}
public int multiply()
{
return x * y;
}
public int divide()
{
solution = x / y;
return solution;
}
}
答案 2 :(得分：0)
在主类中创建每个实例，然后调用相应的方法：
package maincalculator;
//Imports the scanner that I will be using.
import java.util.Scanner;
/**
*
* @author alex
*/
public class MainCalculator {
//Public static void for the class.
public static void main(String[] args) {
//Welcome print at the start of application.
add addition = new add();
sub subtraction = new sub();
div division = new div();
multi multiplication = new multi();
System.out.println("Welcome to the Calculator V1.O");
//Blank line seperator.
System.out.println("");
System.out.println("What would you like to do today?");
System.out.println("");
//The options that will be shown to the program user in the console.
//Option List for the program.
System.out.println("1. Add");
System.out.println("2. Subtract");
System.out.println("3. Divide");
System.out.println("4. Multiply");
//Scans for the selected option.
//Creates a new scanner.
Scanner scan = new Scanner(System.in);
//Checks if the next integer is selected.
//Variables set to load the functions of each calculator.
//Scans the integer choices.
int choice = scan.nextInt();
switch (choice) {
case 1:
addition.addcode();
break;
case 2:
subtraction.subcode();
break;
case 3:
division.divcode();
break;
case 4:
multiplication.multicode();
break;
default:
//Print this line if 1-4 are not selected.
System.out.println("Option Unavailable");
break;
}
}
class add {
public void addcode (){
//Input a new scanner.
Scanner input = new Scanner( System.in );
//Collects the data from number1 and number2.
int number1;
int number2;
int sum;
//Menu name
System.out.println( "Add" );
//Creates the message for the first number.
System.out.print( "Enter your first number: " );
//Creates the message for the second nmber.
number1 = input.nextInt(); //Defines number1
System.out.print( "Enter your second number: " );
number2 = input.nextInt(); //Defines number2
//Use addition symbol between the two numbers.
sum = number1 + number2;
System.out.printf( "Sum equals %d\n", sum);
}
}
class sub {
public void subcode (){
Scanner input = new Scanner( System.in );
int number1;
int number2;
int sum;
System.out.println( "Subtraction" );
System.out.print( "Enter your first number: " );
number1 = input.nextInt(); //Defines number1
System.out.print( "Enter your second number: " );
number2 = input.nextInt(); //Defines number2
sum = number1 - number2;
System.out.printf( "Sum equals %d\n", sum);
}
}
class div {
public void divcode (){
Scanner input = new Scanner( System.in );
int number1;
int number2;
int sum;
System.out.println( "Division" );
System.out.print( "Enter your first number: " );
number1 = input.nextInt(); //Defines number1
System.out.print( "Enter your second number: " );
number2 = input.nextInt(); //Defines number2
sum = number1 / number2;
System.out.printf( "Sum equals %d\n", sum);
}
}
class multi {
public void multicode (){
//Multiplication
//New scanner.
Scanner input = new Scanner( System.in );
//Int number from below.
int number1;
int number2;
//The sum answer displayed.
int sum;
System.out.println( "Multiply" );
System.out.print( "Enter your first number: " );
number1 = input.nextInt(); //Defines number1
System.out.print( "Enter your second number: " );
number2 = input.nextInt(); //Defines number2
sum = number1 * number2;
System.out.printf( "Sum equals %d\n", sum);
}
}
}