/*
	Description:
	Author: Students in CS231
	Date: April 2003
 */
 
import java.io.*;
import java.awt.*;

// Stores objects in binary format
public class DBStorage
{
    public String write(MusicDataBase c) 
    {
        FileDialog fd = new FileDialog(new Frame(), "Where would you like it?", FileDialog.SAVE);
        fd.setDirectory(".");
        fd.setFile("*.*");
        fd.show();
        String filename = fd.getFile();
        System.out.println("Saving Filename = " + filename);
        
        try {
            File data = new File(filename);
            ObjectOutputStream out = new ObjectOutputStream(
                  new FileOutputStream(data));
            out.writeObject(c);
            out.close();    
            return "Database saved to file " + filename;
        } catch (Exception e) {
            return "Error saving to " + filename + ". Database not saved.\n" + e;
        }          
    }
   
    public MusicDataBase read() 
    {

        FileDialog fd = new FileDialog(new Frame(), "Select Input File");
        fd.setFile("input");
        fd.show();
        String filename= fd.getDirectory()+fd.getFile();
        System.out.println("Reading Filename = " + filename);
        MusicDataBase c = null;   
        File data = new File(filename);
        if (data.exists()) {
             c = read(data, filename); 
        }
        else  {
            System.out.println("File " + filename + 
                " not found. Creating new database.");
            c = new MusicDataBase();
        }
        return c;
    }
    
    public MusicDataBase read(File data, String filename) {
        MusicDataBase c = null;
        try {
            ObjectInputStream in = new ObjectInputStream(
               new FileInputStream(data)); 
            c = (MusicDataBase) in.readObject();
            in.close();  
            System.out.println("File " + filename + " read.");
        }
        catch (ClassNotFoundException e)
        {
           System.out.println("Class not found. Creating new Database.\n" + e);
        }
        catch (IOException e) {
           System.out.println("Error reading file " +  filename + "\n" + e);
        }
        return  c;
    }   
      
}