Java example source code file (AppletContext.java)

This example Java source code file (AppletContext.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

applet, appletcontext, audioclip, awt, enumeration, image, inputstream, ioexception, iterator, net, network, string, util

The AppletContext.java Java example source code

/*
 * Copyright (c) 1995, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package java.applet;

import java.awt.Image;
import java.awt.Graphics;
import java.awt.image.ColorModel;
import java.net.URL;
import java.util.Enumeration;
import java.io.InputStream;
import java.io.IOException;
import java.util.Iterator;

/**
 * This interface corresponds to an applet's environment: the
 * document containing the applet and the other applets in the same
 * document.
 * <p>
 * The methods in this interface can be used by an applet to obtain
 * information about its environment.
 *
 * @author      Arthur van Hoff
 * @since       JDK1.0
 */
public interface AppletContext {
    /**
     * Creates an audio clip.
     *
     * @param   url   an absolute URL giving the location of the audio clip.
     * @return  the audio clip at the specified URL.
     */
    AudioClip getAudioClip(URL url);

    /**
     * Returns an <code>Image object that can then be painted on
     * the screen. The <code>url argument that is
     * passed as an argument must specify an absolute URL.
     * <p>
     * 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.
     *
     * @param   url   an absolute URL giving the location of the image.
     * @return  the image at the specified URL.
     * @see     java.awt.Image
     */
    Image getImage(URL url);

    /**
     * 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 <code>name attribute.
     *
     * @param   name   an applet name.
     * @return  the applet with the given name, or <code>null if
     *          not found.
     */
    Applet getApplet(String name);

    /**
     * Finds all the applets in the document represented by this applet
     * context.
     *
     * @return  an enumeration of all applets in the document represented by
     *          this applet context.
     */
    Enumeration<Applet> getApplets();

    /**
     * Requests that the browser or applet viewer show the Web page
     * indicated by the <code>url argument. The browser or
     * applet viewer determines which window or frame to display the
     * Web page. This method may be ignored by applet contexts that
     * are not browsers.
     *
     * @param   url   an absolute URL giving the location of the document.
     */
    void showDocument(URL url);

    /**
     * Requests that the browser or applet viewer show the Web page
     * indicated by the <code>url argument. The
     * <code>target argument indicates in which HTML frame the
     * document is to be displayed.
     * The target argument is interpreted as follows:
     *
     * <center>
     * <tr>
     * <tr>
Target Argument
Description
"_self"  
Show in the window and frame that
     *                                   contain the applet.</tr>
     * <tr>
"_parent"
Show in the applet's parent frame. If
     *                                   the applet's frame has no parent frame,
     *                                   acts the same as "_self".</tr>
     * <tr>
"_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".</tr>
     * <tr>
"_blank" 
Show in a new, unnamed
     *                                   top-level window.</tr>
     * <tr>
name
Show in the frame or window named name. If
     *                        a target named <i>name does not already exist, a
     *                        new top-level window with the specified name is created,
     *                        and the document is shown there.</tr>
     * </table> 
     * <p>
     * An applet viewer or browser is free to ignore <code>showDocument.
     *
     * @param   url   an absolute URL giving the location of the document.
     * @param   target   a <code>String indicating where to display
     *                   the page.
     */
    public void showDocument(URL url, String target);

    /**
     * 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.
     *
     * @param   status   a string to display in the status window.
     */
    void showStatus(String status);

    /**
     * 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.
     * <p>
     * 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
     * <p>
     * @param key key with which the specified value is to be associated.
     * @param stream stream to be associated with the specified key. If this
     *               parameter is <code>null, the specified key is removed
     *               in this applet context.
     * @throws IOException if the stream size exceeds a certain
     *         size limit. Size limit is decided by the implementor of this
     *         interface.
     * @since 1.4
     */
    public void setStream(String key, InputStream stream)throws IOException;

    /**
     * Returns the stream to which specified key is associated within this
     * applet context. Returns <tt>null if the applet context contains
     * no stream for this key.
     * <p>
     * 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
     * <p>
     * @return the stream to which this applet context maps the key
     * @param key key whose associated stream is to be returned.
     * @since 1.4
     */
    public InputStream getStream(String key);

    /**
     * Finds all the keys of the streams in this applet context.
     * <p>
     * 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
     * <p>
     * @return  an Iterator of all the names of the streams in this applet
     *          context.
     * @since 1.4
     */
    public Iterator<String> getStreamKeys();
}


Other Java examples (source code examples)
Here is a short list of links related to this Java AppletContext.java source code file:

  
 The search page
  
 Other Java source code examples at this package level
  
 Click here to learn more about this project

new blog posts