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===== The "this" keyword =====

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  * The "this" reference variable

  * "this" is the name of a reference variable that an object can use to refer to itself.
    * Can be used in only non-static methods.

  * Common use of "this" is to overcome "shadowing" in "set" methods:
    * See [[http://www.leepoint.net/notes-java/data/variables/60shadow-variables.html| notes on "shadowing"]].

<code>
public class Rectangle {
   private int width;
   private int height;

   
   // setHeight method of Rectangle class:
   public void setHeight( int height ) {
      height = height; // ??? Shadowing: Which height is which ???
   }
}







public class Rectangle {
   private int width;
   private int height;

   
   // Avoid shadowing using "this":
   public void setHeight( int height ) {
      this.height = height;
      
      // "This" Rectangle's instance variable height
      // is equal to the value of the input parameter
      // variable height.
   }
}
</code>

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