showdocument.java.bak

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import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import java.net.URL;
import java.net.MalformedURLException;

public class ShowDocument extends Applet implements ActionListener{
	URLWindow urlWindow;
	
	public void init(){
		
		Button button = new Button("Bring up URL window");
		button.addActionListener(this);
		add(button);
		
		urlWindow = new URLWindow(getAppletContext());
		urlWindow.pack();
	}
	
	public void destroy(){
		urlWindow.setVisible(false);
		urlWindow = null;
	}
	
	public void actionPerformed(ActionEvent event){
		urlWindow.setVisible(true);
	}
}

class URLWindow extends Frame implements ActionListener{
	TextField urlField;
	Choice choice;
	AppletContext appletContext;
	
	public URLWindow(AppletContext appletContext){
		super("Show a Document!");
		 this.appletContext = appletContext;
		 
		 GridBagLayout gridBag = new GridBagLayout();
		 GridBagConstraints c = new GridBagConstraints();
		 setLayout(gridBag);
		 
		 Label label1 = new Label("URL of document to show:",Label.RIGHT);
		 gridBag.setConstraints(label1,c);
		 add(label1);
		 
		 urlField = new TextField("http://java.sun.com/",40);
		 urlField.addActionListener(this);
		 c.gridwidth = GridBagConstraints.REMAINDER;
		 c.fill = GridBagConstraints.HORIZONTAL;
		 c.weightx = 1.0;
		 gridBag.setConstraints(urlField,c);
		 add(urlField);
		 
		 Label label2 = new Label("Window/frame to show it in:",Label.RIGHT);
		 
		 c.gridwidth = 1;
		 c.weightx   = 0.0;
		 gridBag.setConstraints(label2,c);
		 add(label2);
		 
		 choice = new Choice();
		 choice.addItem("(browser's choice)");
		 choice.addItem("My Personal Window");
		 choice.addItem("_blank");
		 choice.addItem("_self");
		 choice.addItem("_parent");
		 choice.addItem("_top");
		 c.fill = GridBagConstraints.NONE;
		 c.gridwidth = GridBagConstraints.REMAINDER;
		 c.anchor = GridBagConstraints.WEST;
		 gridBag.setConstraints(choice,c);
		 add(choice);
		 
		 Button button = new Button("Show document");
		 button.addActionListener(this);
		 c.weighty = 1.0;
		 c.ipadx = 10;
		 c.ipady = 10;
		 c.insets =new Insets(5,0,0,0);
		 c.anchor = GridBagConstraints.SOUTH;
		 gridBag.setConstraints(button,c);
		 add(button);
		 
		 addWindowListener(new WindowAdapter(){
		 	public void windowClosing(WindowEvent event){
		 		setVisible(false);
		 	}
		});
	}
	
	public void actionPerformed(ActionEvent event){
		String urlString = urlField.getText();
		URL url = null;
		
		try{
			url = new URL(urlString);
		}catch(MalformedURLException e){
			System.err.println("Malformed URL:"+urlString);
		}
		
		if(url != null){