Java Collision Detection and bounce - Circle and rectangle

Collision detection between circle(any object) and rectangular wall is simple.
For collision detection we simply compare the distances. And if collision between ball and wall is detected, we change the directions of their speeds for bouncing the ball.

Here is the code:
The Circle
    float x, y; // Ball's center x and y
    float speedX, speedY; // Ball's speed per step in x and y
    float radius; // Ball's radius

Collision detect and bounce
    public static void collisionWithWall(Rectangle wall, Ball ball) {
        float ballMinX = wall.x + ball.radius;
        float ballMinY = wall.y + ball.radius;
        float ballMaxX = wall.width - ball.radius;
        float ballMaxY = wall.height - ball.radius;
        if (ball.x < ballMinX) {
            ball.speedX = -ball.speedX; // Reflect along normal
            ball.x = ballMinX; // Re-position the ball at the edge
        } else if (ball.x > ballMaxX) {
            ball.speedX = -ball.speedX;
            ball.x = ballMaxX;
        // May cross both x and y bounds
        if (ball.y < ballMinY) {
            ball.speedY = -ball.speedY;
            ball.y = ballMinY;
        } else if (ball.y > ballMaxY) {
            ball.speedY = -ball.speedY;
            ball.y = ballMaxY;

Full code Download HERE


  1. Could I use the distance between two rectangles if the ball is also a rectangle if taken from an image?


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