AppletContext.java

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package java.applet;

import java.awt.Image;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.Enumeration;
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 1.0
 * @deprecated The Applet API is deprecated, no replacement.
 */
@Deprecated(since = "9", forRemoval = true)
@SuppressWarnings("removal")
public interface AppletContext {

    /**
     * Creates an audio clip.
     *
     * @param  url an absolute {@code URL} giving the location of the audio clip
     * @return the audio clip at the specified {@code 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 {@code 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 {@code URL} giving the location of the image
     * @return the image at the specified {@code 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 {@code 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:
     *
     * <table class="striped">
     * <caption>Target arguments and their descriptions</caption>
     * <thead>
     *   <tr>
     *     <th scope="col">Target Argument
     *     <th scope="col">Description
     * </thead>
     * <tbody>
     *   <tr>
     *     <th scope="row">{@code "_self"}
     *     <td>Show in the window and frame that contain the applet.
     *   <tr>
     *     <th scope="row">{@code "_parent"}
     *     <td>Show in the applet's parent frame. If the applet's frame has no
     *     parent frame, acts the same as "_self".
     *   <tr>
     *     <th scope="row">{@code "_top"}
     *     <td>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>
     *     <th scope="row">{@code "_blank"}
     *     <td>Show in a new, unnamed top-level window.
     *   <tr>
     *     <th scope="row"><i>name</i>
     *     <td>Show in the frame or window named <i>name</i>. If a target named
     *     <i>name</i> does not already exist, a new top-level window with the
     *     specified name is created, and the document is shown there.
     * </tbody>
     * </table>
     * <p>
     * An applet viewer or browser is free to ignore {@code showDocument}.
     *
     * @param  url an absolute {@code 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
     *
     * @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 {@code 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.
     *
     * @param  key key whose associated stream is to be returned
     * @return the stream to which this applet context maps the key
     * @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.
     *
     * @return an {@code Iterator} of all the names of the streams in this
     *         applet context
     * @since 1.4
     */
    public Iterator<String> getStreamKeys();
}