What is the output of the following Java program? Explain in terms of how parame

Question

What is the output of the following Java program? Explain in terms of how parameters are passed in Java.

import java.awt.*;

class PointParameters
{
public static void main(String [] args)
{
int x = 1, y = 1;
Point p = new Point(x, y), q = new Point(x, y);
doubleScale(x, y, p, q);
System.out.println( "(x,y) = " + new Point(x, y) +
" p = " + p + " q = " + q);
}

private static void doubleScale(int x, int y, Point p, Point q)
{
x *= 2;
y *= 2;
p.x *= 2;
p.y *= 2;
q = new Point(x, y);
}
}

Suppose a similar program were written in C# in which all the parameters were ref parameters. What would the output of that program be?

Explanation / Answer

The output from doublescale does the following impact:
x =1
y = 1
p.x=2
p.y=2
q = will remain same as initiated in main function.

The values of x and Y remains unchanged siince they are immutable - constant like values.

The values in P get changed since they are modified in doublescale class, P was not created/nullfied but it was modified.

In the case of q, was totally created - that is existing relation (memory addressing) to q from main was removed and a new one is created, hence q value in main function is not effected.

IF the program is written c# - to get the same result below approach is required.
x - Byval
y - Byval
p - Byref
q - Byval

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.