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diff --git a/docs/examples/introduction/Point.java b/docs/examples/introduction/Point.java
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+/*
+  Copyright (c) Xerox Corporation 1998-2002.  All rights reserved.
+
+  Use and copying of this software and preparation of derivative works based
+  upon this software are permitted.  Any distribution of this software or
+  derivative works must comply with all applicable United States export control
+  laws.
+
+  This software is made available AS IS, and Xerox Corporation makes no warranty
+  about the software, its performance or its conformity to any specification.
+*/
+
+package introduction;
+
+public class Point {
+
+   protected double x = 0;
+   protected double y = 0;
+   protected double theta = 0;
+   protected double rho = 0;
+
+   protected boolean polar = true;
+   protected boolean rectangular = true;
+
+   public double getX(){
+      makeRectangular();
+      return x;
+   }
+
+   public double getY(){
+      makeRectangular();
+      return y;
+   }
+
+   public double getTheta(){
+      makePolar();
+      return theta;
+   }
+
+   public double getRho(){
+      makePolar();
+      return rho;
+   }
+
+   public void setRectangular(double newX, double newY){
+      x = newX;
+      y = newY;
+      rectangular = true;
+      polar = false;
+   }
+
+   public void setPolar(double newTheta, double newRho){
+      theta = newTheta;
+      rho = newRho;
+      rectangular = false;
+      polar = true;
+   }
+
+   public void rotate(double angle){
+      setPolar(theta + angle, rho);
+   }
+
+   public void offset(double deltaX, double deltaY){
+      setRectangular(x + deltaX, y + deltaY);
+   }
+
+   protected void makePolar(){
+      if (!polar){
+	 theta = Math.atan2(y,x);
+	 rho = y / Math.sin(theta);
+	 polar = true;
+      }
+   }
+
+   protected void makeRectangular(){
+      if (!rectangular) {
+		 y = rho * Math.sin(theta);
+		 x = rho * Math.cos(theta);
+		 rectangular = true;
+      }
+   }
+
+   public String toString(){
+      return "(" + getX() + ", " + getY() + ")[" 
+	 + getTheta() + " : " + getRho() + "]";
+   }
+
+   public static void main(String[] args){
+      Point p1 = new Point();
+      System.out.println("p1 =" + p1);
+      p1.setRectangular(5,2);
+      System.out.println("p1 =" + p1);
+      p1.setPolar( Math.PI / 4.0 , 1.0);
+      System.out.println("p1 =" + p1);
+      p1.setPolar( 0.3805 , 5.385);
+      System.out.println("p1 =" + p1);
+   }
+}