import java.applet.*;
import java.awt.*;
import java.net.*;
import java.util.*;


public class StubAppletViewer extends Frame implements AppletContext {

  Applet theApplet = null;
  TextField appletName = new TextField(32);
  Button reloadButton = new Button("Reload");
  Button restartButton = new Button("Restart");
  Vector theApplets = new Vector();
  TextField status = new TextField(32);
  SimpleAppletStub theStub = new SimpleAppletStub(this);

  public static void main(String[] args) {

    StubAppletViewer sav = new StubAppletViewer("Stub Applet Viewer");
    sav.init();
    sav.pack();
    sav.show();

 }

  public void init() {

    add("Center", theStub);
    Panel p1 = new Panel();
    p1.setLayout(new GridLayout(3, 1)); 
    Panel p0 = new Panel();
    p0.setLayout(new FlowLayout(FlowLayout.LEFT));
    p0.add(new Label("URL: "));
    p0.add(appletName);
    p1.add(p0);
    Panel p2 = new Panel();
    p2.add(reloadButton);
    p2.add(restartButton);
    p1.add(p2);
    Panel p4 = new Panel();
    p4.setLayout(new FlowLayout(FlowLayout.LEFT));
    p4.add(new Label("Status: "));
    status.setEditable(false);
    p4.add(status);
    p1.add(p4);
    add("South", p1);
 
  }

  public StubAppletViewer(String s) {

    super(s);
 
  }

  public void loadApplet(String name) {

    removeApplet();
    if (name != null && !name.equals("")) {
       try {
         Class c = Class.forName(name); 
         theApplet = (Applet) c.newInstance(); 
         theApplet.setStub(theStub);
         theStub.add(theApplet);
         theApplets.addElement(theApplet);
         theApplet.init();
         theStub.activate();
         theStub.validate();
         theApplet.start();
         theApplet.resize(100, 100);
         pack();
      }
       catch (ClassNotFoundException e) {
         System.err.println(e);
       }
       catch (InstantiationException e) {
         System.err.println(e);
       }
       catch (IllegalAccessException e) {
         System.err.println(e);
       }

    }

  }


  public void removeApplet() {

    if (theApplet != null) {
      theApplet.stop();
      theStub.deactivate();
      theApplet.destroy();
      theStub.remove(theApplet);
      theApplets.removeElement(theApplet);
      theApplet = null;
    }

  }


  public void reload() {

    String name = appletName.getText();

    if (theApplet != null) {
      Class c = theApplet.getClass();
      name = c.getName();
      removeApplet();
    }

    loadApplet(name);

  }

  public void restart() {

   if (theApplet != null) {
      theApplet.stop();
      theApplet.start();
    }
    else loadApplet(appletName.getText());

  }

  public boolean action(Event e, Object what) {

    if (e.target == restartButton) {
      restart();
      return true;
    }
    else if (e.target == reloadButton) {
      reload();
      return true;
    }
    else if (e.target == appletName) {
      loadApplet(appletName.getText());
      return true;
    }

    return false;

  }

  public Image getImage(URL u) {
    return Toolkit.getDefaultToolkit().getImage(u);
  }

  public AudioClip getAudioClip(URL u) {
    return new NullAudioClip();
  }

  public Applet getApplet(String s) {
    return null;
  }

  public Enumeration getApplets() {
    return (Enumeration) theApplets;
  }

  public void showDocument(URL url) {};

  public void showDocument(URL url, String target) {};

  public void showStatus(String s) {
    status.setText(s);
  }

  public void paint(Graphics g) {

    if (theApplet != null) theApplet.paint(g);

  }

}