Add all the A tasks

Task/Animation/Java/animation.java

@@ -0,0 +1,59 @@
+import java.awt.event.MouseAdapter;
+import java.awt.event.MouseEvent;
+import java.util.Timer;
+import java.util.TimerTask;
+import javax.swing.JFrame;
+import javax.swing.JLabel;
+
+public class Rotate extends JFrame {
+  String text = "Hello World! ";
+  JLabel label = new JLabel(text);
+  boolean rotRight = true;
+  int startIdx = 0;
+
+  public Rotate() {
+    label.addMouseListener(new MouseAdapter() {
+      @Override
+      public void mouseClicked(MouseEvent evt) {
+        rotRight = !rotRight;
+      }
+    });
+    add(label);
+    pack();
+    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+    setVisible(true);
+  }
+
+  public static void main(String[] args) {
+    final Rotate rot = new Rotate();
+    TimerTask task = new TimerTask() {
+      public void run() {
+        if (rot.rotRight) {
+          rot.startIdx++;
+          if (rot.startIdx >= rot.text.length()) {
+            rot.startIdx -= rot.text.length();
+          }
+        } else {
+          rot.startIdx--;
+          if (rot.startIdx < 0) {
+            rot.startIdx += rot.text.length();
+          }
+        }
+        rot.label.setText(getRotatedText(rot.text, rot.startIdx));
+      }
+    };
+    Timer timer = new Timer(false);
+    timer.schedule(task, 0, 500);
+  }
+
+  public static String getRotatedText(String text, int startIdx) {
+    String ret = "";
+    int i = startIdx;
+    do {
+      ret += text.charAt(i) + "";
+      i++;
+      i = i % text.length();
+    } while (i != startIdx);
+    return ret;
+  }
+}