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public  class  java.applet.Applet
    extends  java.awt.Panel  (II-§1.33)
{
        // Constructors
    public Applet();	§3.1.1

        // Methods
    public void destroy();	§3.1.2
    public AppletContext getAppletContext();	§3.1.3
    public String getAppletInfo();	§3.1.4
    public AudioClip getAudioClip(URL  url);	§3.1.5
    public AudioClip getAudioClip(URL  url, String  name);	§3.1.6
    public URL getCodeBase();	§3.1.7
    public URL getDocumentBase();	§3.1.8
    public Image getImage(URL  url);	§3.1.9
    public Image getImage(URL  url, String  name);	§3.1.10
    public String getParameter(String  name);	§3.1.11
    public String[][] getParameterInfo();	§3.1.12
    public void init();	§3.1.13
    public boolean isActive();	§3.1.14
    public void play(URL  url);	§3.1.15
    public void play(URL  url, String  name);	§3.1.16
    public void resize(Dimension  d);	§3.1.17
    public void resize(int  width, int  height);	§3.1.18
    public final void setStub(AppletStub  stub);	§3.1.19
    public void showStatus(String  msg);	§3.1.20
    public void start();	§3.1.21
    public void stop();	§3.1.22
}

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.

The default constructor for an applet

This method is called by the browser or applet viewer to inform thisapplet that it is being reclaimed and that it should destroy any resources that it has allocated. The stop (II-§3.1.22) method will always be called before destroy.

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 (II-§3.1.13) 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:

start (II-§3.1.21).

Determines this applet's context, which allows the applet to query and affect the environment in which it runs.

This environment of an applet represents the document that contains the applet.

Returns:

the applet's context.

Returns information about this applet. An applet should override this method to return a String containing information about the author, version, and copyright of the applet.

The implementation of this method provided by the Applet class returns null.

Returns:

a string containing information about the author, version and copyright of the applet.

Returns the AudioClip object (II-§3.4) specified by the URL argument.

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

Returns:

the audio clip at the specified URL.

Returns the AudioClip object (II-§3.4) specified by the URL and name arguments.

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 the audio clip

name - the location of the audio clip, relative to the url argument

Returns:

the audio clip at the specified URL.

Returns:

the URL (I-§4.8) of this applet.

See Also:

getDocumentBase (II-§3.1.8).

Returns:

the URL (I-§4.8) of the document that contains this applet.

See Also:

getCodeBase (II-§3.1.7).

Returns an Image object (II-§1.24) that can then be painted on the screen. The url that is passed as an argument must specify an absolute URL.

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

Returns:

the image at the specified URL.

Returns an Image object (II-§1.24) that can then be painted on the screen. The url argument must specify an absolute URL. The name argument is a specifier that is relative to the url argument.

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

name - the location of the image, relative to the url argument

Returns:

the image at the specified URL.

Returns the value of the named parameter in the HTML tag. For example, if this applet is specified as

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

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

The name argument is case insensitive.

Parameters:

name - a parameter name

Returns:

the value of the named parameter.

Returns information about the parameters than can are understood by this applet. An applet should override this method to return an array of array of Strings describing these parameters.

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.

Returns:

An array describing the parameters this applet looks for.

This method is called by the browser or applet viewer to inform this applet that it has been loaded into the system. It is always called before the first time that the start method (II-§3.1.21) is called.

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 (II-§3.1.2) method to kill them.

The implementation of this method provided by the Applet class does nothing.

See Also:

stop (II-§3.1.22).

Determines if thisapplet is active. An applet is marked active just before its start method (II-§3.1.21) is called. It becomes inactive immediately after its stop (II-§3.1.22) method is called.

Returns:

true if the applet is active; false otherwise.

See Also:

start (II-§3.1.21).

Plays the audio clip at the specified absolute URL. Nothing happens if the audio clip cannot be found.

Parameters:

url - an absolute URL giving the location of the audio clip

Plays the audio clip given the URL and a specifier that's relative to it. Nothing happens if the audio clip cannot be found.

Parameters:

url - an absolute URL giving the base location of the audio clip

name - the location of the audio clip, relative to the url argument

Requests that this applet be resized.

Parameters:

d - An object giving the new width and height

Overrides:

resize in class Component (II-§1.10.65).

Requests that this applet be resized.

Parameters:

width - the new requested width for the applet

height - the new requested height for the applet

Overrides:

resize in class Component (II-§1.10.66).

Sets this applet's stub. This is done by automatically by the system.

Parameters:

stub - The new stub

Requests that the argument string be displayed in the "status window." Many browsers and applet viewers provide such a "status window" where the application can inform users of its current state.

Parameters:

msg - a string to display in the status window

This method is called by the browser or applet viewer to inform this applet that it should start its execution. It is called after the init method and each time the applet is revisited in a Web page.

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 (II-§3.1.22) to suspend the animation.

The implementation of this method provided by the Applet class does nothing.

See Also:

init (II-§3.1.13)
destroy (II-§3.1.2).

This method is called by the browser or applet viewer to inform this applet that it should stop its execution. It is called when the Web page that contains this applet has been replaced by another page and also just before the applet is to be destroyed.

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 (II-§3.1.21) 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:

init (II-§3.1.13)
destroy (II-§3.1.2).

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