有什么我们不需要用0初始化char VarName的方法吗？

如何解决有什么我们不需要用0初始化char VarName的方法吗？

我试图使用数组和切换大小写（用于+，-，*，/）创建一个计算器。但是我想我的char []总是位于0的索引处...请帮助我。（有什么方法我们不需要用0初始化char运算符？这只是我的getData类，如果您想查看整个计算器代码，我也会发布它。 谢谢。♥

/* DESIRED I/O
enter array length: 3
2
+

5
-

5
=
(answer)*/


//wholeCode; //struggling in this...please help me
package calculator1;

import java.util.Scanner;

public class getdata0  {
int number;
char operator;
double answer;
double num[]= new double[number];
char op[]=new char[number];
int i;  
    void getData0()
    {
    
        try (Scanner object = new Scanner(System.in)) {
        
                System.out.print("Enter number: ");
                number=object.nextInt();
                
            double num[]= new double[number];
            char op[]=new char[number];
                for(i=0;i<num.length;i++)
                {
                    System.out.println("getting data"+(i+1));
                    num[i]=object.nextInt();
                    op[i]=object.next().charAt(0);
                    
                }
                }
        }
}
package calculator1;

public class addition extends getdata0 
{
    /*int number;    IGNORE!!
    double num[]= new double[number];
    double answer;*/
    
    double add()
    {System.out.println("adding...");
        /*for(int add=0;add<num.length;add++)
        {
            answer=answer+num[add];
            }
*///NOT SURE WHICH ONE TO USE.
    
        /*for(double no:num)
        {
        answer+=no;
        }*/
    return answer;
    }
}
package calculator1;

public class substraction extends addition{
double sub()
public class division extends substraction{
double div() 
public class multiplication extends division{
double mul()
    
public class chooseoperators extends multiplication 
{

    void chooseOperator()
    {int y=0;
    
        System.out.println("Operating...");
        
        for(y=0;y<op.length;y++)
        
        System.out.println("Operating inside switch");
        
        switch(op[y])
        { 
        case '+': add();
        break;
        case '-':sub();
        break;
        case '/':div();
        break;
        case '*':mul();
        break;
        case '=':System.out.println(answer);
        break;
        }System.out.println("operation end");
}}


package calculator1;

public class Run extends chooseoperators
{

    public static void main(String[] args) {
    
        chooseoperators objectC=new chooseoperators();
        
        objectC.getData0();
    
        System.out.println(objectC.num.length);
        objectC.chooseOperator();
        System.out.println(objectC.op.length);
        }
}