title: How do we draw abstract method in uml class diagram
body: <pre><code>public abstract class Shape {   
      abstract int area();
  }
  </code></pre>
  
  <p>How do we draw the UML class diagram for the abstract method? Use <code>+</code>, <code>-</code> or <code>#</code>?</p>
  
  <pre><code>public class Room { 
      int nWindows;   
  }
  </code></pre>
  
  <p>And what if the class instance variable doesn't have public, private or protected?</p>