message

.classpath

+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.8"/>
+	<classpathentry kind="src" path="src"/>
+	<classpathentry kind="output" path="bin"/>
+</classpath>

.gitignore

+/bin/

.project

+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>project Ak</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+	</natures>
+</projectDescription>

.settings/org.eclipse.jdt.core.prefs

+eclipse.preferences.version=1
+org.eclipse.jdt.core.compiler.codegen.inlineJsrBytecode=enabled
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.8
+org.eclipse.jdt.core.compiler.codegen.unusedLocal=preserve
+org.eclipse.jdt.core.compiler.compliance=1.8
+org.eclipse.jdt.core.compiler.debug.lineNumber=generate
+org.eclipse.jdt.core.compiler.debug.localVariable=generate
+org.eclipse.jdt.core.compiler.debug.sourceFile=generate
+org.eclipse.jdt.core.compiler.problem.assertIdentifier=error
+org.eclipse.jdt.core.compiler.problem.enumIdentifier=error
+org.eclipse.jdt.core.compiler.source=1.8

src/BouncingBall.java

+import java.awt.*;
+import javax.swing.*;
+ 
+public class BouncingBall extends JPanel {
+ 
+  // Box height and width
+  int w;
+  int h;
+ 
+  // Ball Size
+  float r = 20; 
+  float diameter = r * 2;
+ 
+  // Center of Call
+  float X = r + 50;
+  float Y = r + 20;
+ 
+  // Direction
+  float dx = 3;
+  float dy = 3;
+ 
+  public BouncingBall() {
+ 
+    Thread thread = new Thread() {
+      public void run() {
+        while (true) {
+ 
+          w = getWidth();
+          h = getHeight();
+ 
+          X = X + dx ;
+          Y = Y + dy;
+ 
+          if (X - r < 0) {
+            dx = -dx; 
+            X = r; 
+          } else if (X + r > w) {
+            dx = -dx;
+            X = w - r;
+          }
+ 
+          if (Y - r < 0) {
+            dy = -dy;
+            Y = r;
+          } else if (Y + r > h) {
+            dy = -dy;
+            Y = h - r;
+          }
+          repaint();
+ 
+          try {
+            Thread.sleep(50);
+          } catch (InterruptedException ex) {
+          }
+ 
+        }
+      }
+    };
+    thread.start();
+  }
+ 
+  public void paintComponent(Graphics g) {
+    super.paintComponent(g);
+    g.setColor(Color.BLUE);
+    g.fillOval((int)(X-r), (int)(Y-r), (int)diameter, (int)diameter);
+  }
+ 
+  public static void main(String[] args) {
+    JFrame.setDefaultLookAndFeelDecorated(true);
+    JFrame frame = new JFrame("Bouncing Ball");
+    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+    frame.setSize(300, 200);
+    frame.setContentPane(new BouncingBall());
+    frame.setVisible(true);
+  }
+}