import java.io.FileReader;
import java.io.Reader;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.text.*;

// The following can be commented out for version 1.3 
import pre13.AsyncBoxView;

/**
 * This example demonstrates changing the StyledEditorKit 
 * to use the AsyncBoxView instead of a BoxView for the 
 * vertical arrangement of the lines/paragraphs.
 * 
 * @author  Timothy Prinzing
 * @version 1.2 07/19/99
 */
public class StyleExample {

    public static void main(String[] args) {
	if (args.length != 1) {
	    System.err.println("give filename argument");
	    System.exit(1);
	}
	try {
	    EditorKit kit = new AsyncStyledEditorKit();
	    JTextPane pane = new JTextPane();
	    pane.setEditorKit(kit);

	    JScrollPane scroller = new JScrollPane();
	    JViewport vp = scroller.getViewport();
	    vp.add(pane);
	    vp.setBackingStoreEnabled(true);
	    
	    JFrame f = new JFrame();
	    f.getContentPane().add(scroller);
	    f.pack();
	    f.setSize(600, 600);
	    f.setVisible(true);
	    f.addWindowListener(new WindowAdapter() {
                public void windowClosing(WindowEvent e) {
		    System.exit(0);
		}
	    });

	    Thread loader = new AsyncLoader(pane.getDocument(), new FileReader(args[0])); 
	    loader.start();

	} catch (Throwable e) {
	    e.printStackTrace();
	    System.exit(1);
	}
    }

    static class AsyncLoader extends Thread {

	AsyncLoader(Document doc, Reader in) {
	    super("document-loader");
	    setPriority(Thread.MIN_PRIORITY);
	    this.in = in;
	    this.doc = doc;
	}

        public void run() {
	    try {
		char[] buff = new char[4096];
		int nch;
		while ((nch = in.read(buff, 0, buff.length)) != -1) {
		    doc.insertString(doc.getLength(), new String(buff, 0, nch), null);
		}
	    } catch (Throwable e) {
		e.printStackTrace();
		System.exit(1);
	    }
	}

	Reader in;
	Document doc;
    }

    /**
     * A slightly modified version of the <code>javax.swing.text.StyledEditorKit</code>
     * that replaces the view of the section element with one that does asynchronous
     * layout.
     */
    public static class AsyncStyledEditorKit extends StyledEditorKit implements ViewFactory {

	/**
	 * Fetches a factory that is suitable for producing 
	 * views of any models that are produced by this
	 * kit.  This is implemented to return View implementations
	 * for the following kinds of elements:
	 * <ul>
	 * <li>AbstractDocument.ContentElementName
	 * <li>AbstractDocument.ParagraphElementName
	 * <li>AbstractDocument.SectionElementName
	 * <li>StyleConstants.ComponentElementName
	 * <li>StyleConstants.IconElementName
	 * </ul>
	 *
	 * @return the factory
	 */
        public ViewFactory getViewFactory() {
	    return this;
	}

	/**
	 * Builds an AsyncBoxView for the <em>section</em> element,
	 * otherwise provides the default factory behavior.
	 */
        public View create(Element elem) {
	    String kind = elem.getName();
	    if ((kind != null) && (kind.equals(AbstractDocument.SectionElementName))) {
		return new AsyncBoxView(elem, View.Y_AXIS);
	    }
	    ViewFactory f = super.getViewFactory();
	    return f.create(elem);
	}

    }


}