basic doubt in program

Jul 01, 2009 07:07:37

import java.awt.*;

import java.awt.event.*;

class MyCanvas extends Canvas

{

public void paint(Graphics g)

{ g.setColor(new Color(255,0,0));
g.fillOval(5,5,20,20);

g.setColor(Color.blue);

g.fillOval(40,10,20,20);

g.setColor(Color.yellow);

g.fillRect(10,20,40,50);

}

}

public class TestCanvas

{
Frame f;
void Launchmc()
{

MyCanvas mc=new MyCanvas();

f=new Frame("drawings");
f.add(mc);

f.setSize(300,200);
f.setVisible(true);

f.addWindowListener(
new WindowAdapter(){ public void windowClosing(WindowEvent e)
{ System.exit(0);
}

});

}

public static void main(String args[])

{

TestCanvas tc=new TestCanvas();
tc.Launchmc();

}

}

Why is it that I can make object of MyCanvas class in Launchmc() method
and also access that object from Launchmc(),MyCanvas class is not public

Jul 01, 2009 07:12:36

By not defining an access level the class receives default access, which means that it is accessible by classes in the same package. Since you did not have any package declarations for either class they are both in the default package. Since they are in the same package TestCanvas can access MyCanvas.

Jul 01, 2009 07:51:52

thanks

if i shift MyCanvas class to other .java file
[that file will contain only MyCanvas class]

will this java program TestCanvas9.java work

both files will be in same folder

Jul 01, 2009 09:26:02

Please use more informative thread titles. You want people who are interested in your problem to look at your thread, so they need to know what it is about.

Jul 01, 2009 09:43:33

I agree

Jul 01, 2009 09:55:52

linus dale wrote:thanks

if i shift MyCanvas class to other .java file
[that file will contain only MyCanvas class]

will this java program TestCanvas9.java work

both files will be in same folder

As long as you don't put either of the classes in different packages it should work.

Jul 01, 2009 11:48:39

thanks Smith

it worked