public classAppletextendsPanel
TheApplet class must be the superclass of any applet that is to be embedded in a Web page or viewed by the Java Applet Viewer. TheApplet class provides a standard interface between applets and their environment.
| Modifier and Type | Class and Description |
|---|---|
protected class | Applet.AccessibleAppletThis class implements accessibility support for the Applet class. |
Panel.AccessibleAWTPanelContainer.AccessibleAWTContainerComponent.AccessibleAWTComponent,Component.BaselineResizeBehavior,Component.BltBufferStrategy,Component.FlipBufferStrategyBOTTOM_ALIGNMENT,CENTER_ALIGNMENT,LEFT_ALIGNMENT,RIGHT_ALIGNMENT,TOP_ALIGNMENTABORT,ALLBITS,ERROR,FRAMEBITS,HEIGHT,PROPERTIES,SOMEBITS,WIDTH| Constructor and Description |
|---|
Applet()Constructs a new Applet. |
| Modifier and Type | Method and Description |
|---|---|
void | destroy()Called by the browser or applet viewer to inform this applet that it is being reclaimed and that it should destroy any resources that it has allocated. |
AccessibleContext | getAccessibleContext()Gets the AccessibleContext associated with this Applet. |
AppletContext | getAppletContext()Determines this applet's context, which allows the applet to query and affect the environment in which it runs. |
String | getAppletInfo()Returns information about this applet. |
AudioClip | getAudioClip(URL url)Returns the AudioClip object specified by theURL argument. |
AudioClip | getAudioClip(URL url,String name)Returns the AudioClip object specified by theURL andname arguments. |
URL | getCodeBase()Gets the base URL. |
URL | getDocumentBase()Gets the URL of the document in which this applet is embedded. |
Image | getImage(URL url)Returns an Image object that can then be painted on the screen. |
Image | getImage(URL url,String name)Returns an Image object that can then be painted on the screen. |
Locale | getLocale()Gets the locale of the applet. |
String | getParameter(String name)Returns the value of the named parameter in the HTML tag. |
String[][] | getParameterInfo()Returns information about the parameters that are understood by this applet. |
void | init()Called by the browser or applet viewer to inform this applet that it has been loaded into the system. |
boolean | isActive()Determines if this applet is active. |
boolean | isValidateRoot()Indicates if this container is a validate root. |
staticAudioClip | newAudioClip(URL url)Get an audio clip from the given URL. |
void | play(URL url)Plays the audio clip at the specified absolute URL. |
void | play(URL url,String name)Plays the audio clip given the URL and a specifier that is relative to it. |
void | resize(Dimension d)Requests that this applet be resized. |
void | resize(int width, int height)Requests that this applet be resized. |
void | setStub(AppletStub stub)Sets this applet's stub. |
void | showStatus(String msg)Requests that the argument string be displayed in the "status window". |
void | start()Called by the browser or applet viewer to inform this applet that it should start its execution. |
void | stop()Called by the browser or applet viewer to inform this applet that it should stop its execution. |
add,add,add,add,add,addContainerListener,addImpl,addPropertyChangeListener,addPropertyChangeListener,applyComponentOrientation,areFocusTraversalKeysSet,countComponents,deliverEvent,doLayout,findComponentAt,findComponentAt,getAlignmentX,getAlignmentY,getComponent,getComponentAt,getComponentAt,getComponentCount,getComponents,getComponentZOrder,getContainerListeners,getFocusTraversalKeys,getFocusTraversalPolicy,getInsets,getLayout,getListeners,getMaximumSize,getMinimumSize,getMousePosition,getPreferredSize,insets,invalidate,isAncestorOf,isFocusCycleRoot,isFocusCycleRoot,isFocusTraversalPolicyProvider,isFocusTraversalPolicySet,layout,list,list,locate,minimumSize,paint,paintComponents,paramString,preferredSize,print,printComponents,processContainerEvent,processEvent,remove,remove,removeAll,removeContainerListener,removeNotify,setComponentZOrder,setFocusCycleRoot,setFocusTraversalKeys,setFocusTraversalPolicy,setFocusTraversalPolicyProvider,setFont,setLayout,transferFocusDownCycle,update,validate,validateTreeaction,add,addComponentListener,addFocusListener,addHierarchyBoundsListener,addHierarchyListener,addInputMethodListener,addKeyListener,addMouseListener,addMouseMotionListener,addMouseWheelListener,bounds,checkImage,checkImage,coalesceEvents,contains,contains,createImage,createImage,createVolatileImage,createVolatileImage,disable,disableEvents,dispatchEvent,enable,enable,enableEvents,enableInputMethods,firePropertyChange,firePropertyChange,firePropertyChange,firePropertyChange,firePropertyChange,firePropertyChange,firePropertyChange,firePropertyChange,firePropertyChange,getBackground,getBaseline,getBaselineResizeBehavior,getBounds,getBounds,getColorModel,getComponentListeners,getComponentOrientation,getCursor,getDropTarget,getFocusCycleRootAncestor,getFocusListeners,getFocusTraversalKeysEnabled,getFont,getFontMetrics,getForeground,getGraphics,getGraphicsConfiguration,getHeight,getHierarchyBoundsListeners,getHierarchyListeners,getIgnoreRepaint,getInputContext,getInputMethodListeners,getInputMethodRequests,getKeyListeners,getLocation,getLocation,getLocationOnScreen,getMouseListeners,getMouseMotionListeners,getMousePosition,getMouseWheelListeners,getName,getParent,getPeer,getPropertyChangeListeners,getPropertyChangeListeners,getSize,getSize,getToolkit,getTreeLock,getWidth,getX,getY,gotFocus,handleEvent,hasFocus,hide,imageUpdate,inside,isBackgroundSet,isCursorSet,isDisplayable,isDoubleBuffered,isEnabled,isFocusable,isFocusOwner,isFocusTraversable,isFontSet,isForegroundSet,isLightweight,isMaximumSizeSet,isMinimumSizeSet,isOpaque,isPreferredSizeSet,isShowing,isValid,isVisible,keyDown,keyUp,list,list,list,location,lostFocus,mouseDown,mouseDrag,mouseEnter,mouseExit,mouseMove,mouseUp,move,nextFocus,paintAll,postEvent,prepareImage,prepareImage,printAll,processComponentEvent,processFocusEvent,processHierarchyBoundsEvent,processHierarchyEvent,processInputMethodEvent,processKeyEvent,processMouseEvent,processMouseMotionEvent,processMouseWheelEvent,remove,removeComponentListener,removeFocusListener,removeHierarchyBoundsListener,removeHierarchyListener,removeInputMethodListener,removeKeyListener,removeMouseListener,removeMouseMotionListener,removeMouseWheelListener,removePropertyChangeListener,removePropertyChangeListener,repaint,repaint,repaint,repaint,requestFocus,requestFocus,requestFocusInWindow,requestFocusInWindow,reshape,revalidate,setBackground,setBounds,setBounds,setComponentOrientation,setCursor,setDropTarget,setEnabled,setFocusable,setFocusTraversalKeysEnabled,setForeground,setIgnoreRepaint,setLocale,setLocation,setLocation,setMaximumSize,setMinimumSize,setName,setPreferredSize,setSize,setSize,setVisible,show,show,size,toString,transferFocus,transferFocusBackward,transferFocusUpCyclepublic Applet() throwsHeadlessException
Note: Many methods injava.applet.Applet may be invoked by the applet only after the applet is fully constructed; applet should avoid calling methods injava.applet.Applet in the constructor.
HeadlessException - if GraphicsEnvironment.isHeadless() returns true.GraphicsEnvironment.isHeadless()public final void setStub(AppletStub stub)
If there is a security manager, its checkPermission method is called with theAWTPermission("setAppletStub") permission if a stub has already been set.
stub - the new stub.SecurityException - if the caller cannot set the stubpublic boolean isActive()
start method is called. It becomes inactive just before itsstop method is called.public URL getDocumentBase()
The document base is:http://java.sun.com/products/jdk/1.2/index.html
http://java.sun.com/products/jdk/1.2/index.html
URL of the document that contains this applet.getCodeBase()public URL getCodeBase()
URL of the directory which contains this applet.getDocumentBase()public String getParameter(String name)
<applet code="Clock" width=50 height=50> <param name=Color value="blue"> </applet>
then a call togetParameter("Color") returns the value"blue".
Thename argument is case insensitive.
name - a parameter name.null if not set.public AppletContext getAppletContext()
This environment of an applet represents the document that contains the applet.
public void resize(int width, int height)
public void resize(Dimension d)
public boolean isValidateRoot()
Applet objects are the validate roots, and, therefore, they override this method to returntrue.
isValidateRoot in class ContainertrueContainer.isValidateRoot()public void showStatus(String msg)
msg - a string to display in the status window.public Image getImage(URL url)
Image object that can then be painted on the screen. Theurl 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.
url - an absolute URL giving the location of the image.Imagepublic Image getImage(URL url,String name)
Image object that can then be painted on the screen. Theurl argument must specify an absolute URL. Thename argument is a specifier that is relative to theurl 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.
url - an absolute URL giving the base location of the image.name - the location of the image, relative to theurl argument.Imagepublic static final AudioClip newAudioClip(URL url)
url - points to the audio clippublic AudioClip getAudioClip(URL url)
AudioClip object specified by theURL 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.
url - an absolute URL giving the location of the audio clip.AudioClippublic AudioClip getAudioClip(URL url,String name)
AudioClip object specified by theURL andname 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.
url - an absolute URL giving the base location of the audio clip.name - the location of the audio clip, relative to theurl argument.AudioClippublic String getAppletInfo()
String containing information about the author, version, and copyright of the applet. The implementation of this method provided by theApplet class returnsnull.
public Locale getLocale()
getLocale in class ComponentComponent.setLocale(java.util.Locale)public String[][] getParameterInfo()
Strings describing these parameters. Each element of the array should be a set of threeStrings 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 theApplet class returnsnull.
public void play(URL url)
url - an absolute URL giving the location of the audio clip.public void play(URL url,String name)
url - an absolute URL giving the base location of the audio clip.name - the location of the audio clip, relative to theurl argument.public void init()
start method is called. A subclass ofApplet should override this method if it has initialization to perform. For example, an applet with threads would use theinit method to create the threads and thedestroy method to kill them.
The implementation of this method provided by theApplet class does nothing.
public void start()
init method and each time the applet is revisited in a Web page. A subclass ofApplet 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 thestart method to resume animation, and thestop method to suspend the animation.
Note: some methods, such asgetLocationOnScreen, can only provide meaningful results if the applet is showing. BecauseisShowing returnsfalse when the applet'sstart is first called, methods requiringisShowing to returntrue should be called from aComponentListener.
The implementation of this method provided by theApplet class does nothing.
public void stop()
A subclass ofApplet 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 thestart method to resume animation, and thestop method to suspend the animation.
The implementation of this method provided by theApplet class does nothing.
public void destroy()
stop method will always be called beforedestroy. A subclass ofApplet 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 theinit method to create the threads and thedestroy method to kill them.
The implementation of this method provided by theApplet class does nothing.
public AccessibleContext getAccessibleContext()
getAccessibleContext in interface AccessiblegetAccessibleContext in class Panel