How to make my FileSaver being able to output any type stuff?

Hi,

I am writing a Class file (FileSaver.java), which has the outline:

public class FileSaver {
    private JFileChooser _fileChooser = null;

    public FileSaver()
    {
        _fileChooser = new JFileChooser(new File("."));
        _fileChooser.setFileSelectionMode(JFileChooser.FILES_ONLY);
    }

    public void saveFile()
    {
        ... //writes to the external file
    }

} //end of class
This class will pup up a gui to let user choose the directory and file
name etc. It will be called anytime when the major program needs to save
something. Right now, when something needs to be saved, the code for
saving is repeated typed in that place. I hope to pull out those code
and create an object which can do saving for anybody, anytime.

Sometime it is several lines of text needs to be saved, sometimes it is
other things(e.g. image). I hope this class file FileSaver can be as
generic as possible. So I am thinking to let the major program pass
something(OutpurStream?) as arguments. I am not clear how to achieve
this purpose. Could you give me some help?

Thank you.