Exception Handling Messages

Question

Hi,
I am trying to code the program to:
1. display the message in the no arg ctor "Invalid Dimension"
2. display the message in the try block passing good values
"height and width are valid "
3. display the message in the try block passing bad values
"height and width must be greater than zero"
I have tried many different ways and can't figure it out. Can someone please
help.
Thanks
import javax.swing.JApplet;
import java.awt.Graphics;
//A user defined exception must inherit from Throwable. 
//Exception inherits from Throwable.
class IllegalDimensionException extends Exception//*****
  //Exception class will see String
  public IllegalDimensionException()//no arg ctor
    super("Invalid Dimension");
  //Allows unique message to be created rather than using
  //no arg ctor message
  public IllegalDimensionException(String errmessage)//1 arg ctor
    super(errmessage);
class Rectangle extends Shape 
      private static int counter = 0;
      private int width;
      private int height;
      Rectangle( )
         ++counter;
      Rectangle(int x, int y, int w, int h)
         super(x,y);
         width  = w;
         height = h;
      ++counter;
       public void setDimension(int w, int h) throws IllegalDimensionException
          if(h < 0 || w < 0)//*****
             throw new IllegalDimensionException();//throw initiates an exception//*****
       width  =  w;
          height =  h;
       public void set(int x, int y, int w, int h)
          loc.set(x,y);
          width  = w;
          height = h;
        public int getWidth()   {return width;}
        public int getHeight()  {return height;}
        public int perimeter() 
           return (2 * width) + (2 * height);
        public double area()      
          return width * height;
     public void draw(Graphics g)
          g.drawRect(loc.getX(),loc.getY(),width,height);
     public String toString()
       return
          "(("+ loc.getX() +","+ loc.getY() +"),"+ width +","+ height +")";
     public static int recCount()
           return counter;
public class FinalA8 extends JApplet
    Rectangle r1;
    Rectangle r2;
    Rectangle r3;
    Circle c1;
    Circle c2;    
    public void init()
        r1 = new Rectangle( );
        r1.set(300,50,50,40);
        r2 = new Rectangle(400,50,80,60);//x,y,width,height
        r3 = new Rectangle();
     public void paint(Graphics g)
        r3.setLocation(500,50);
        try//*****
          r3.setDimension(-3, 4);
        //catch uses 1 arg ctor
        catch(IllegalDimensionException e)//*****
          //System.out.println("height & width must be greater than zero");
        try//*****
          r3.setDimension(100, 150);
        catch(IllegalDimensionException e)//*****
          System.out.println("height & width are valid");
}

Answer 1

Thanks for your reply.
I can't figure out these compile errors?
C:\java>javac FinalA8.java
FinalA8.java:346: ')' expected.
       catch(IllegalDimension Exception e)
                                       ^
FinalA8.java:355: Type expected.
        ("r3:  xCoord =" + r3.getX() + "  yCoord=" + r3.getY()
         ^
FinalA8.java:131: Exception IllegalDimensionException must be caught, or it must
be declared in the throws clause of this constructor.
         setDimension(h,w);
                     ^
FinalA8.java:150: Exception IllegalDimensionException must be caught, or it must
be declared in the throws clause of this method.
          setDimension(h,w);
                      ^
4 errors
import javax.swing.JApplet;
import java.awt.Graphics;
//A user defined exception must inherit from Throwable. 
//Exception inherits from Throwable.
class IllegalDimensionException extends Exception//*****
  //Exception class will see String
  public IllegalDimensionException()//no arg ctor
    super("Invalid Dimension");
  //Allows unique message to be created rather than using
  //no arg ctor message
  public IllegalDimensionException(String errmessage)//1 arg ctor
    super(errmessage);
class Rectangle extends Shape 
      private static int counter = 0;
      private int width;
      private int height;
      Rectangle( )
         ++counter;
      Rectangle(int x, int y, int w, int h)
          super(x,y);
          setDimension(h,w);
          ++counter;
       public void setDimension(int w, int h) throws IllegalDimensionException
          if(h < 0 || w < 0)//*****
             throw new IllegalDimensionException();//throw initiates an exception//*****
       setDimension(h,w);
       public void set(int x, int y, int w, int h)
          loc.set(x,y);
          setDimension(h,w);
        public int getWidth()   {return width;}
        public int getHeight()  {return height;}
        public int perimeter() 
           return (2 * width) + (2 * height);
        public double area()      
          return width * height;
     public void draw(Graphics g)
          g.drawRect(loc.getX(),loc.getY(),width,height);
     public String toString()
       return
          "(("+ loc.getX() +","+ loc.getY() +"),"+ width +","+ height +")";
     public static int recCount()
           return counter;
public class FinalA8 extends JApplet
    Rectangle r1;
    Rectangle r2;
    Rectangle r3;
    public void init()
        r1 = new Rectangle( );
        r2 = new Rectangle();
        r3 = new Rectangle();
     public void paint(Graphics g)
        r1.setLocation(300,50);
        r2.setLocation(400,50);
        r3.setLocation(500,50);
        try//*****
          r1.setDimension(-3, 4);
        //catch uses 1 arg ctor and prints message below
        catch(IllegalDimensionException e)//*****
          System.out.println("height & width must be greater than zero");
        try//*****
          r2.setDimension(100, 150);
        //catch uses 1 arg ctor and prints message below
        catch(IllegalDimensionException e)//*****
          System.out.println("Width and Height are valid");
       try//*****
         r3.setDimension(-0,-0);
       //catch uses 1 arg ctor and prints message in no arg ctor
       catch(IllegalDimension Exception e)
         System.out.println(e);}
        g.drawString
        ("r3: xCoord =" + r3.getX() + "  yCoord=" + r3.getY()
         + "  Width =" + r3.getWidth()
         + "  Height=" + r3.getHeight(), 20,150);
        g.drawString
         ("r's created:  "+Rectangle.recCount(),20,175);
        r1.draw(g);
        r2.draw(g);
        r3.draw(g);