To synchronize part of a method preceded by synchronized(this). : Synchronize « Thread « SCJP

1. SCJP
2. Thread
3. Synchronize

import java.awt.Rectangle;

class MyClass {
  Rectangle rect = new Rectangle(1, 1, 100, 300);

  void doit() {
    int x = 504;
    int y = x / 3;
    synchronized (this) {
      rect.width -= x;
      rect.height -= y;
    }
  }
}