Java tutorial
/* * @(#)Seek.java 1.2 01/03/13 * * Copyright (c) 1999-2001 Sun Microsystems, Inc. All Rights Reserved. * * Sun grants you ("Licensee") a non-exclusive, royalty free, license to use, * modify and redistribute this software in source and binary code form, * provided that i) this copyright notice and license appear on all copies of * the software; and ii) Licensee does not utilize the software in a manner * which is disparaging to Sun. * * This software is provided "AS IS," without a warranty of any kind. ALL * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING ANY * IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR * NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN AND ITS LICENSORS SHALL NOT BE * LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING * OR DISTRIBUTING THE SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR ITS * LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT, * INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER * CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF * OR INABILITY TO USE SOFTWARE, EVEN IF SUN HAS BEEN ADVISED OF THE * POSSIBILITY OF SUCH DAMAGES. * * This software is not designed or intended for use in on-line control of * aircraft, air traffic, aircraft navigation or aircraft communications; or in * the design, construction, operation or maintenance of any nuclear * facility. Licensee represents and warrants that it will not use or * redistribute the Software for such purposes. */ import java.awt.BorderLayout; import java.awt.Button; import java.awt.Component; import java.awt.Frame; import java.awt.Panel; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.io.File; import java.io.FileNotFoundException; import javax.media.ConfigureCompleteEvent; import javax.media.ControllerEvent; import javax.media.ControllerListener; import javax.media.Duration; import javax.media.EndOfMediaEvent; import javax.media.Manager; import javax.media.MediaLocator; import javax.media.Player; import javax.media.PrefetchCompleteEvent; import javax.media.RealizeCompleteEvent; import javax.media.ResourceUnavailableEvent; import javax.media.SizeChangeEvent; import javax.media.Time; import javax.media.control.FramePositioningControl; import javax.media.protocol.DataSource; /** * Sample program to demonstrate FramePositioningControl. */ public class Seek extends Frame implements ControllerListener, ActionListener { Player p; FramePositioningControl fpc; Object waitSync = new Object(); boolean stateTransitionOK = true; int totalFrames = FramePositioningControl.FRAME_UNKNOWN; Panel cntlPanel; Button fwdButton; Button bwdButton; Button rndButton; /** * Given a DataSource, create a player and use that player * as a player to playback the media. */ public boolean open(DataSource ds) { System.err.println("create player for: " + ds.getContentType()); try { p = Manager.createPlayer(ds); } catch (Exception e) { System.err.println("Failed to create a player from the given DataSource: " + e); return false; } p.addControllerListener(this); p.realize(); if (!waitForState(p.Realized)) { System.err.println("Failed to realize the player."); return false; } // Try to retrieve a FramePositioningControl from the player. fpc = (FramePositioningControl) p.getControl("javax.media.control.FramePositioningControl"); if (fpc == null) { System.err.println("The player does not support FramePositioningControl."); System.err.println("There's no reason to go on for the purpose of this demo."); return false; } Time duration = p.getDuration(); if (duration != Duration.DURATION_UNKNOWN) { System.err.println("Movie duration: " + duration.getSeconds()); totalFrames = fpc.mapTimeToFrame(duration); if (totalFrames != FramePositioningControl.FRAME_UNKNOWN) System.err.println("Total # of video frames in the movies: " + totalFrames); else System.err.println("The FramePositiongControl does not support mapTimeToFrame."); } else { System.err.println("Movie duration: unknown"); } // Prefetch the player. p.prefetch(); if (!waitForState(p.Prefetched)) { System.err.println("Failed to prefetch the player."); return false; } // Display the visual & control component if there's one. setLayout(new BorderLayout()); cntlPanel = new Panel(); fwdButton = new Button("Forward"); bwdButton = new Button("Backward"); rndButton = new Button("Random"); fwdButton.addActionListener(this); bwdButton.addActionListener(this); rndButton.addActionListener(this); cntlPanel.add(fwdButton); cntlPanel.add(bwdButton); cntlPanel.add(rndButton); Component vc; if ((vc = p.getVisualComponent()) != null) { add("Center", vc); } add("South", cntlPanel); setVisible(true); return true; } public void addNotify() { super.addNotify(); pack(); } /** * Block until the player has transitioned to the given state. * Return false if the transition failed. */ boolean waitForState(int state) { synchronized (waitSync) { try { while (p.getState() < state && stateTransitionOK) waitSync.wait(); } catch (Exception e) { } } return stateTransitionOK; } public void actionPerformed(ActionEvent ae) { String command = ae.getActionCommand(); if (command.equals("Forward")) { int dest = fpc.skip(1); System.err.println("Step forward " + dest + " frame."); } else if (command.equals("Backward")) { int dest = fpc.skip(-1); System.err.println("Step backward " + dest + " frame."); } else if (command.equals("Random")) { if (totalFrames == FramePositioningControl.FRAME_UNKNOWN) System.err.println("Cannot jump to a random frame."); else { int randomFrame = (int) (totalFrames * Math.random()); randomFrame = fpc.seek(randomFrame); System.err.println("Jump to a random frame: " + randomFrame); } } int currentFrame = fpc.mapTimeToFrame(p.getMediaTime()); if (currentFrame != FramePositioningControl.FRAME_UNKNOWN) System.err.println("Current frame: " + currentFrame); } /** * Controller Listener. */ public void controllerUpdate(ControllerEvent evt) { if (evt instanceof ConfigureCompleteEvent || evt instanceof RealizeCompleteEvent || evt instanceof PrefetchCompleteEvent) { synchronized (waitSync) { stateTransitionOK = true; waitSync.notifyAll(); } } else if (evt instanceof ResourceUnavailableEvent) { synchronized (waitSync) { stateTransitionOK = false; waitSync.notifyAll(); } } else if (evt instanceof EndOfMediaEvent) { p.setMediaTime(new Time(0)); //p.start(); //p.close(); //System.exit(0); } else if (evt instanceof SizeChangeEvent) { } } /** * Main program */ public static void main(String[] args) { if (args.length == 0) { prUsage(); System.exit(0); } MediaLocator ml; if ((ml = new MediaLocator(args[0])) == null) { System.err.println("Cannot build media locator from: " + args[0]); prUsage(); System.exit(0); } DataSource ds = null; // Create a DataSource given the media locator. try { ds = Manager.createDataSource(ml); } catch (Exception e) { System.err.println("Cannot create DataSource from: " + ml); System.exit(0); } Seek seek = new Seek(); if (!seek.open(ds)) System.exit(0); } static void prUsage() { System.err.println("Usage: java Seek <url>"); } }