Starting out with BlueJ

Lesson 4 - Sending Info to Class with a Constructor

import java.io.*;

public class decision2
{
public int a;

public decision2(int n)
{ a = n;
}

public void start() throws IOException
 {input in = new input();
     
   if (a % 2 == 0)
     System.out.println("It is even");
   else
     System.out.println("It is odd");
    }	
}

Copy and paste the above class into BlueJ. Call project decision. New Class - decision2
Compile it.
Create an instance of it by right mouse clicking on it.
New - decision2()
Enter a number to give n a value.
Right Mouse click on instance of class that has been created (in Red).
Click on start() function.