update

src/main/java/PingPong/GamePanel.java

@@ -45,7 +45,7 @@ public class GamePanel extends JPanel implements Runnable {
             }
         if(collisionChecker.didTouchPaddle(ball, new Rectangle(paddle_1.x, paddle_1.y1, paddle_1.width, paddle_1.height))) {
             ball.xVelocity = Math.abs(ball.xVelocity);
-            ball.xVelocity++;       // increasing ball's speed!
+            ball.xVelocity++;
             if (ball.yVelocity > 0)
                 ball.yVelocity++;
             else
@@ -53,6 +53,16 @@ public class GamePanel extends JPanel implements Runnable {
             ball.setXDirection(ball.xVelocity);
             ball.setYDirection(ball.yVelocity);
         }
+        if(collisionChecker.didTouchPaddle(ball, new Rectangle(paddle_2.x, paddle_2.y2, paddle_2.width, paddle_2.height))) {
+            ball.xVelocity = Math.abs(ball.xVelocity);
+            ball.xVelocity++;
+            if (ball.yVelocity > 0)
+                ball.yVelocity++;
+            else
+                ball.yVelocity--;
+            ball.setXDirection(-ball.xVelocity);
+            ball.setYDirection(ball.yVelocity);
+        }
     }