How to Accurately Center Components within a Resizable JFrame?

Finding the Precise Center of a Resizable JFrame

Background:
When designing JFrame applications, accurately positioning elements on the screen is crucial. However, determining the exact center point can be challenging, especially when the JFrame is resizable.

The Problem:
This question highlights two main concerns:

1. Despite specifying a width of 400, objects consistently bounce off the JFrame screen 10 pixels short.
2. How to determine the exact center point of a resizable JFrame regardless of its size.

Solution:
1. Compensating for JFrame Border:
The discrepancy in object position is likely due to the JFrame's border. Frames have a decorative border that reduces the actual paintable area. To account for this, calculate the width and height as follows:

width - border.width
height - border.height

2. Dynamic Center Point Calculation:
To obtain the exact center point at any screen size, follow these steps:

1. Get the current JFrame dimensions: frame.getWidth() and frame.getHeight().
2. Calculate the center point coordinates: width / 2 and height / 2.
3. Adjust for the border (if necessary): width / 2 - border.width / 2 and height / 2 - border.height / 2.

Alternative Solution:
Alternatively, consider using the setLocationRelativeTo(null) method to center the JFrame relative to the screen, regardless of its size.

Improved Example:
To use the improved center point calculation in your code:

int centerX = (frame.getWidth() / 2) - (frame.getBorder().getBorderInsets().right / 2);
int centerY = (frame.getHeight() / 2) - (frame.getBorder().getBorderInsets().bottom / 2);

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