Senderpublic class Sender extends Applet implements ActionListener
| Fields Summary |
|---|
| private String | myName | | private TextField | nameField | | private TextArea | status | | private String | newline |
| Methods Summary |
|---|
| public void | actionPerformed(java.awt.event.ActionEvent event)
Applet receiver = null;
String receiverName = nameField.getText(); //Get name to
//search for.
receiver = getAppletContext().getApplet(receiverName);
if (receiver != null) {
//Use the instanceof operator to make sure the applet
//we found is a Receiver object.
if (!(receiver instanceof Receiver)) {
status.append("Found applet named "
+ receiverName + ", "
+ "but it's not a Receiver object."
+ newline);
} else {
status.append("Found applet named "
+ receiverName + newline
+ " Sending message to it."
+ newline);
//Cast the receiver to be a Receiver object
//(instead of just an Applet object) so that the
//compiler will let us call a Receiver method.
((Receiver)receiver).processRequestFrom(myName);
}
} else {
status.append("Couldn't find any applet named "
+ receiverName + "." + newline);
}
| | public java.lang.String | getAppletInfo()
return "Sender by Kathy Walrath";
| | public java.awt.Insets | getInsets()
return new Insets(3,3,3,3);
| | public void | init()
GridBagLayout gridBag = new GridBagLayout();
GridBagConstraints c = new GridBagConstraints();
setLayout(gridBag);
Label receiverLabel = new Label("Receiver name:",
Label.RIGHT);
gridBag.setConstraints(receiverLabel, c);
add(receiverLabel);
nameField = new TextField(getParameter("RECEIVERNAME"),
10);
c.fill = GridBagConstraints.HORIZONTAL;
gridBag.setConstraints(nameField, c);
add(nameField);
nameField.addActionListener(this);
Button button = new Button("Send message");
c.gridwidth = GridBagConstraints.REMAINDER; //end row
c.anchor = GridBagConstraints.WEST; //stick to the
//text field
c.fill = GridBagConstraints.NONE; //keep the button
//small
gridBag.setConstraints(button, c);
add(button);
button.addActionListener(this);
status = new TextArea(5, 60);
status.setEditable(false);
c.anchor = GridBagConstraints.CENTER; //reset to the default
c.fill = GridBagConstraints.BOTH; //make this big
c.weightx = 1.0;
c.weighty = 1.0;
gridBag.setConstraints(status, c);
add(status);
myName = getParameter("NAME");
Label senderLabel = new Label("(My name is " + myName + ".)",
Label.CENTER);
c.weightx = 0.0;
c.weighty = 0.0;
gridBag.setConstraints(senderLabel, c);
add(senderLabel);
newline = System.getProperty("line.separator");
| | public void | paint(java.awt.Graphics g)
g.drawRect(0, 0,
getSize().width - 1, getSize().height - 1);
|
|
