java.applet

Interface AppletContext

public interface AppletContext

This interface corresponds to an applet's environment: the document containing the applet and the other applets in the same document.

The methods in this interface can be used by an applet to obtain information about its environment.

Since:
JDK1.0

Method Summary

Applet
getApplet(String name)
Finds and returns the applet in the document represented by this applet context with the given name.
Enumeration
getApplets()
Finds all the applets in the document represented by this applet context.
AudioClip
getAudioClip(URL url)
Creates an audio clip.
Image
getImage(URL url)
Returns an Image object that can then be painted on the screen.
InputStream
getStream(String key)
Returns the stream to which specified key is associated within this applet context.
Iterator
getStreamKeys()
Finds all the keys of the streams in this applet context.
void
setStream(String key, InputStream stream)
Associates the specified stream with the specified key in this applet context.
void
showDocument(URL url)
Replaces the Web page currently being viewed with the given URL.
void
showDocument(URL url, String target)
Requests that the browser or applet viewer show the Web page indicated by the url argument.
void
showStatus(String status)
Requests that the argument string be displayed in the "status window".

Method Details

getApplet

public Applet getApplet(String name)
Finds and returns the applet in the document represented by this applet context with the given name. The name can be set in the HTML tag by setting the name attribute.
Parameters:
name - an applet name.
Returns:
the applet with the given name, or null if not found.

getApplets

public Enumeration getApplets()
Finds all the applets in the document represented by this applet context.
Returns:
an enumeration of all applets in the document represented by this applet context.

getAudioClip

public AudioClip getAudioClip(URL url)
Creates an audio clip.
Parameters:
url - an absolute URL giving the location of the audio clip.
Returns:
the audio clip at the specified URL.

getImage

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

This method always returns immediately, whether or not the image exists. When the 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.
See Also:
Image

getStream

public InputStream getStream(String key)
Returns the stream to which specified key is associated within this applet context. Returns null if the applet context contains no stream for this key.

For security reasons, mapping of streams and keys exists for each codebase. In other words, applet from one codebase cannot access the streams created by an applet from a different codebase

Parameters:
key - key whose associated stream is to be returned.
Returns:
the stream to which this applet context maps the key
Since:
JDK1.4

getStreamKeys

public Iterator getStreamKeys()
Finds all the keys of the streams in this applet context.

For security reasons, mapping of streams and keys exists for each codebase. In other words, applet from one codebase cannot access the streams created by an applet from a different codebase

Returns:
an Iterator of all the names of the streams in this applet context.
Since:
JDK1.4

setStream

public void setStream(String key,
                      InputStream stream)
            throws IOException
Associates the specified stream with the specified key in this applet context. If the applet context previously contained a mapping for this key, the old value is replaced.

For security reasons, mapping of streams and keys exists for each codebase. In other words, applet from one codebase cannot access the streams created by an applet from a different codebase

Parameters:
key - key with which the specified value is to be associated.
stream - stream to be associated with the specified key. If this parameter is null, the specified key is removed in this applet context.
Since:
JDK1.4

showDocument

public void showDocument(URL url)
Replaces the Web page currently being viewed with the given URL. This method may be ignored by applet contexts that are not browsers.
Parameters:
url - an absolute URL giving the location of the document.
Usages and Demos :

View More Examples of showDocument(URL url)
   1:   
   2:     AppletContext ac = getAppletContext();
   3:     URL oldURL = getDocumentBase();
   4:         ...
   5:     try {
   6:       ac.showDocument(newURL);
   7:     }
   8:     catch (MalformedURLException e) {
   9:     }

View Full Code Here
   1: import websphinx.*;
   2: import java.applet.AppletContext;
   3: import java.io.File;
   4:         ...
   5: public class Browser implements LinkViewListener {
   6:     protected AppletContext context;
   7:     protected String frameName;
   8:         ...
   9: 
  10:     public Browser (AppletContext context) {
  11:         this.context = context;
  12:         ...
  13:         else
  14:             context.showDocument(url);

View Full Code Here
   1:     Choice choice;
   2:     AppletContext appletContext;
   3: 
   4:         ...
   5:     public URLWindow(AppletContext appletContext) {
   6:         super("Show a Document!");
   7:         ...
   8:             if (choice.getSelectedIndex() == 0) {
   9:                 appletContext.showDocument(url);
  10:             } else {

View Full Code Here
   1: import java.awt.BorderLayout;
   2: import java.applet.AppletContext;
   3: import javax.swing.JApplet;
   4:         ...
   5: 
   6:                AppletContext browser = getAppletContext();
   7: 
   8:         ...
   9:                browser.showDocument( newDocument );

View Full Code Here

showDocument

public void showDocument(URL url,
                         String target)
Requests that the browser or applet viewer show the Web page indicated by the url argument. The target argument indicates in which HTML frame the document is to be displayed. The target argument is interpreted as follows:

Target ArgumentDescription
"_self" Show in the window and frame that contain the applet.
"_parent"Show in the applet's parent frame. If the applet's frame has no parent frame, acts the same as "_self".
"_top" Show in the top-level frame of the applet's window. If the applet's frame is the top-level frame, acts the same as "_self".
"_blank" Show in a new, unnamed top-level window.
nameShow in the frame or window named name. If a target named name does not already exist, a new top-level window with the specified name is created, and the document is shown there.

An applet viewer or browser is free to ignore showDocument.

Parameters:
url - an absolute URL giving the location of the document.
target - a String indicating where to display the page.
Usages and Demos :

View More Examples of showDocument(URL url,String target)
   1: {
   2:   public Help(AppletContext myContext, String myURL, String where)
   3:   {
   4:         ...
   5: 
   6:       myContext.showDocument(helpURL, "RCOS_Online_Help_Window");
   7:     }
   8:     catch (MalformedURLException e)
   9:     {

View Full Code Here
   1: {
   2:   public Help (AppletContext myContext, String myURL, String where)
   3:   {
   4:         ...
   5:       URL helpURL = new URL(myURL + where);
   6:       myContext.showDocument(helpURL,"RCOS_Online_Help_Window");
   7:     }
   8:     catch (MalformedURLException e)
   9:     {

View Full Code Here
   1:                   {
   2:                      AppletContext context = getAppletContext();
   3:         ...
   4:                      context.showDocument(url, "right");
   5:                   }
   6:                });
   7:          } 

View Full Code Here
   1: public class Gateway extends Label {
   2:     AppletContext m_ac;
   3:     Main m_a;
   4:         ...
   5:         if (null != m_ac)
   6:             m_ac.showDocument(u, "content");
   7:         if (null != m_xm)
   8:             m_xm.select(false);
   9:         m_xm = m;

View Full Code Here
   1: public class Gateway extends Label {
   2:     AppletContext m_ac;
   3:     Main m_a;
   4:         ...
   5:         if (null != m_ac)
   6:             m_ac.showDocument(u, "content");
   7:         if (null != m_xm)
   8:             m_xm.select(false);
   9:         m_xm = m;

View Full Code Here

showStatus

public void showStatus(String status)
Requests that the argument string be displayed in the "status window". Many browsers and applet viewers provide such a window, where the application can inform users of its current state.
Parameters:
status - a string to display in the status window.