I have simple usecase but seems tricky to me atleast.
I have class
public class Operation {
private int a,b;
public Operation(){
}
public Operation(int a,int b){
this.a=a;
this.b=b;
}
public int calculate()
{
return (a+b);
}
}
and four classes that extends Operation
public class Addition extends Operation {
public Addition(){
super();
}
public Addition(int a,int b){
super(a,b);
}
public int calculate(int a,int b)
{
return (a+b);
}
}
public class Subtraction extends Operation {
public Subtraction()
{
}
public Subtraction(int a,int b)
{
super(a,b);
}
public int calculate(int a,int b)
{
return (a-b);
}
}
public class Multiplication extends Operation {
public Multiplication()
{
}
public Multiplication(int a,int b)
{
super(a,b);
}
public int calculate(int a,int b)
{
return (a*b);
}
}
public class Division extends Operation {
public Division()
{
}
public Division(int a,int b)
{
super(a,b);
}
public int calculate(int a,int b)
{
return (a/b);
}
}
and my Main method has to do follow
public class CalculationTest {
public static void main(String[] args) {
Operation op=new Addition(100,200);
System.out.println(op.calculate());
op=new Subtraction();
System.out.println(op.calculate()); //this should print -100 as output
op=new Multiplication();
System.out.println(op.calculate()); //this should print 2000 as output
op=new Division();
System.out.println(op.calculate()); //this should print 0 as output
}
}
I have to get output 300 -100 2000 0 but I am getting output as 300 0 0 0
Thanks in advance
I have to get output 300 -100 2000 0 but I am getting output as 300 0 0 0
That is because you are not giving them any input.
Operation op=new Addition(100,200);
This has input and it works.
op=new Subtraction();
This has no input so the values default to 0 and the result is 0.
If you want to subtract two values, you still have to provide them, try
op = new Subtraction(100, 200);