Java Doc for Applet.java in  » 6.0-JDK-Core » Applet » java » applet » Java Source Code / Java DocumentationJava Source Code and Java Documentation

The Applet class must be the superclass of any applet that is to be embedded in a Web page or viewed by the Java Applet Viewer. The Applet class provides a standard interface between applets and their environment.
author:
   Arthur van Hoff
author:
   Chris Warth
version:
   1.89, 05/05/07
since:
   JDK1.0

This method always returns immediately, whether or not the audio clip exists.

This method always returns immediately, whether or not the audio clip exists.

Note: Many methods in java.applet.Applet may be invoked by the applet only after the applet is fully constructed; applet should avoid calling methods in java.applet.Applet in the constructor.
exception:
  HeadlessException - if GraphicsEnvironment.isHeadless()returns true.
See Also:   java.awt.GraphicsEnvironment.isHeadless
since:
   1.4

A subclass of Applet should override this method if it has any operation that it wants to perform before it is destroyed. For example, an applet with threads would use the init method to create the threads and the destroy method to kill them.

The implementation of this method provided by the Applet class does nothing.
See Also:   java.applet.Applet.init
See Also:   java.applet.Applet.start
See Also:   java.applet.Applet.stop

This environment of an applet represents the document that contains the applet. the applet's context.

The implementation of this method provided by the Applet class returns null. a string containing information about the author, version, andcopyright of the applet.

This method always returns immediately, whether or not the audio clip exists. When this applet attempts to play the audio clip, the data will be loaded.
Parameters:
  url - an absolute URL giving the location of the audio clip. the audio clip at the specified URL.
See Also:   java.applet.AudioClip

This method always returns immediately, whether or not the audio clip exists. When this applet attempts to play the audio clip, the data will be loaded.
Parameters:
  url - an absolute URL giving the base location of theaudio clip.
Parameters:
  name - the location of the audio clip, relative to theurl argument. the audio clip at the specified URL.
See Also:   java.applet.AudioClip

 http://java.sun.com/products/jdk/1.2/index.html
 

 http://java.sun.com/products/jdk/1.2/index.html
 

This method always returns immediately, whether or not the image exists. When this applet attempts to draw the image on the screen, the data will be loaded. The graphics primitives that draw the image will incrementally paint on the screen.
Parameters:
  url - an absolute URL giving the location of the image. the image at the specified URL.
See Also:   java.awt.Image

This method always returns immediately, whether or not the image exists. When this applet attempts to draw the image on the screen, the data will be loaded. The graphics primitives that draw the image will incrementally paint on the screen.
Parameters:
  url - an absolute URL giving the base location of the image.
Parameters:
  name - the location of the image, relative to theurl argument. the image at the specified URL.
See Also:   java.awt.Image

 <applet code="Clock" width=50 height=50>
 <param name=Color value="blue">
 </applet>
 

then a call to getParameter("Color") returns the value "blue".

The name argument is case insensitive.
Parameters:
  name - a parameter name. the value of the named parameter,or null if not set.

Each element of the array should be a set of three Strings containing the name, the type, and a description. For example:

 String pinfo[][] = {
 {"fps",    "1-10",    "frames per second"},
 {"repeat", "boolean", "repeat image loop"},
 {"imgs",   "url",     "images directory"}
 };
 

The implementation of this method provided by the Applet class returns null. an array describing the parameters this applet looks for.

A subclass of Applet should override this method if it has initialization to perform. For example, an applet with threads would use the init method to create the threads and the destroy method to kill them.

The implementation of this method provided by the Applet class does nothing.
See Also:   java.applet.Applet.destroy
See Also:   java.applet.Applet.start
See Also:   java.applet.Applet.stop

If there is a security manager, its checkPermission method is called with the AWTPermission("setAppletStub") permission if a stub has already been set.
Parameters:
  stub - the new stub.
exception:
  SecurityException - if the caller cannot set the stub

A subclass of Applet should override this method if it has any operation that it wants to perform each time the Web page containing it is visited. For example, an applet with animation might want to use the start method to resume animation, and the stop method to suspend the animation.

Note: some methods, such as getLocationOnScreen, can only provide meaningful results if the applet is showing. Because isShowing returns false when the applet's start is first called, methods requiring isShowing to return true should be called from a ComponentListener.

The implementation of this method provided by the Applet class does nothing.
See Also:   java.applet.Applet.destroy
See Also:   java.applet.Applet.init
See Also:   java.applet.Applet.stop
See Also:   java.awt.Component.isShowing
See Also:   java.awt.event.ComponentListener.componentShown(java.awt.event.ComponentEvent)

A subclass of Applet should override this method if it has any operation that it wants to perform each time the Web page containing it is no longer visible. For example, an applet with animation might want to use the start method to resume animation, and the stop method to suspend the animation.

The implementation of this method provided by the Applet class does nothing.
See Also:   java.applet.Applet.destroy
See Also:   java.applet.Applet.init