Java puzzle 17: Classes and objects

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The output of this code is 2y2. Add only one statement at line 20. As a result of your statement, the output of the program becomes 9×5.
What is that statement?

Java puzzle 17: Classes and objects

Level: Hard

public class MyClass
{
  int i = 2;
  String str;
  
  MyClass(String str)
  {
    this.str = str;
  }
  int myMethod(int i, String str)
  {
    this.i = i += 2;
    this.str = str;
    return(i + 4);
  }
  public static void main(String[] args)
  {
    MyClass mc = new MyClass("x");
    MyClass mc2 = new MyClass("y");
    // add your statement here!
    System.out.print(mc.i);
    System.out.print(mc2.str);
    System.out.print(mc2.i);
  }
}

Author: Sar Maroof

Answer explanation

The statement should reassign the variable i of the object mc.
The same statement should reassign the value of the variable i and the object str of the object mc2.
To do that we need to use the method myMethod. We can use the method to reassign the value of the variable i and the value of the object str of the object mc2.
To reassign the value of the variable i of the object mc, we can simply reassign its value to the vlaue that the method myMethod returns as follows.
mc.i = mc2.myMethod(3, “x”);

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Sar Maroof is graduated from HBO Amsterdam "higher professional education". He is a professional computer programming teacher, gives master classes and publishes technical articles. His experience with developing software started from 2001 and he has worked as a software developer for several big as well as small companies and later as a freelancer. He is the author of Java quizmaster and Build a Java application in 7 days.