jdialog class

[mgl70]

Hi ,

I have a question regarding JDialog classes.
I have 2 classes that extend JDialog class.
I am creating a empty randomaccessfile when I use Dialog1 class.I close the dialog1 class . Next I need to call the randomaccessfile from dialog2 class.
for this I wrote a getFile() method in dialog1 class.
when I call that method from dialog2 class, I am getting null instead of randomaccessfile.

dialog1 class
{
public RandomAccessFile getFile()
{
return file;
}
}
---------------------------------
dialog2 class
{

Dialog1 d1 = new Dialog1();
RandomAccessFile file = d1.getFile();
//here I need to get the file since I need to write data in the file. but I am getting null here. what should I do?

}
Canot I get any info once I closed the dialog.
I appreciate your help.

thanks,

 

[prosper]

// create a file for testing, for opening and writing output
import java.io.RandomAccessFile;
import java.io.IOException;
import javax.swing.*;
import java.awt.*;
class DialogDemo extends JFrame
{
public DialogDemo()
{
super("Frame1");
}
public static void main(String args[])
{
DialogDemo ddObj = new DialogDemo();
ddObj.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
ddObj.setSize(400,400);
ddObj.setVisible(true);
FileDialog d1 = new FileDialog(ddObj);
d1.show();
if (d1.getFile()!=null)
{
System.out.println( d1.getDirectory()+d1.getFile() );
}
RandomAccessFile rf;
try
{
rf = new RandomAccessFile(d1.getDirectory()+d1.getFile(), "rw");
rf.seek(rf.length());
rf.writeUTF("last line"+"\r");
rf.close();
}
catch (IOException ie)
{System.out.println("error in opening file or writing file!");}
//RandomAccessFile file = d1.getFile();
//here I need to get the file since I need to write data in the file. but I am getting null here. what should I do?
}

}

 

[prosper]

// if case for checking correctness in selecting input file
RandomAccessFile rf;
if (d1.getFile()!=null)
{
try
{
rf = new RandomAccessFile(d1.getDirectory()+d1.getFile(), "rw");
rf.seek(rf.length());
rf.writeUTF("last line"+"\r");
rf.close();
}
catch (IOException ie)
{System.out.println("error in opening file or writing file!");}
//RandomAccessFile file = d1.getFile();
//here I need to get the file since I need to write data in the file. but I am getting null here. what should I do?
}// endif

 

[mgl70]

Thank you very much.but my problem is I am not getting file. if I get file I can able to write.


But my question was . I have 2 java classes dialog1,dialog2.
Somebody wrote these class.I did not write those.

dialog1 extends JDialog.
constructor: d1 = new dialog1(panel1);


dialog2 extends JDialog.
constructor: d2 = new dialog1(panel1);

In the dialog1, I am creating a randomaccessfile.close the dialog.
Next I open dialog2. Here I need to get the randomaccessfile
from dialog1 class.
In dialog1 class ,I wrote a method getFile().

In dialog2 class, I want to get the file because I need to write some info to that file.
In dialog2 . I gave like this.
file = d1.getfile();

here ,I should get file. Then I can write into any thing to that file.
But "file" variable(dialog2 class) is giving "null" because
It is not getting file from dialog1 class.
what is my problem?

I appreciate your help.