ImportExportFileDialog.java

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.nio.ByteBuffer;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.charset.Charset;

class ImportExportFileDialog
implements ImportExportDialog
{
    CirSim cframe;
    private static String circuitDump;
    Action type;
    private static String directory = ".";

    ImportExportFileDialog(CirSim f, Action type)
    {
	if ( directory.equals(".") )
	{
	    File file = new File("circuits");
	    if ( file.isDirectory() )
		directory = "circuits";
	}
	this.type = type;
	cframe = f;
    }

    public void setDump(String dump)
    {
	circuitDump = dump;
    }

    public String getDump()
    {
	return circuitDump;
    }

    public void execute()
    {
	FileDialog fd = new FileDialog(new Frame(),
			(type == Action.EXPORT) ? "Save File" :
			"Open File",
			(type == Action.EXPORT) ? FileDialog.SAVE :
			FileDialog.LOAD );
	fd.setDirectory(directory);
	fd.setVisible(true);
	String file = fd.getFile();
	String dir = fd.getDirectory();
	if ( dir != null )
	    directory = dir;
	if ( file == null )
	    return;
	System.err.println(dir + File.separator + file);
	if ( type == Action.EXPORT )
	{
	    try
	    {
		writeFile(dir + file);
	    }
	    catch (Exception e)
	    {
		e.printStackTrace();
	    }
	}
	else
	{
	    try
	    {
		String dump = readFile(dir + file);
		circuitDump = dump;
		cframe.readSetup(circuitDump);
	    }
	    catch (Exception e)
	    {
		e.printStackTrace();
	    }
	}
    }

    private static String readFile(String path)
    throws IOException, FileNotFoundException
    {
	FileInputStream stream = null;
	try
	{
	    stream = new FileInputStream(new File(path));
	    FileChannel fc = stream.getChannel();
	    MappedByteBuffer bb = fc.map(FileChannel.MapMode.READ_ONLY,
					 0, fc.size());
	    return Charset.forName("UTF-8").decode(bb).toString();
	}
	finally
	{
	    stream.close();
	}
    }

    private static void writeFile(String path)
    throws IOException, FileNotFoundException
    {
	FileOutputStream stream = null;
	try
	{
	    stream = new FileOutputStream(new File(path));
	    FileChannel fc = stream.getChannel();
	    ByteBuffer bb = Charset.forName("UTF-8").encode(circuitDump);
	    fc.write(bb);
	}
	finally
	{
	    stream.close();
	}
    }
}