![]() The following example shows an AWT file-selection dialog and then tries to import and play the selected media file. Since QuickTime itself can be extended, QTJ can pick up support for formats such as DivX and Ogg Vorbis through the use of third-party QuickTime components. QTJ offers access to most of the native QuickTime library, includingĪs a wrapper around QuickTime, QTJ also inherits support for a vast collection of media formats and codecs, including MPEG-1, MPEG-4, H.264, AAC, Sorenson Video, Flash, 3GPP, WAV, AIFF, and more. For this reason, it can only run on systems that have the QuickTime libraries installed, namely the classic Mac OS (which is no longer supported), Mac OS X, and Windows. It is important to remember that QTJ is not a Java implementation of QuickTime, it is a Java wrapper around native QuickTime calls. However, as Apple owns the "QuickTime" trademark, there is no realistic chance of a namespace collision, the prevention of which is the purpose of the package naming convention. The Cocoa-based QTKit is a similar attempt to put an object-oriented layer atop the procedural QuickTime library, using Objective-C.Īpple's use of the top-level package name quicktime violates the Java Language's Specification convention that packages use a reverse-domain-name scheme, such as. The result is more like a genuine object-oriented API than other C-to-Java adaptations (such as JOGL, which dumps the OpenGL header files into classes with thousands of static methods). For example, the Movie struct is the basis of the class, with functions like NewMovieFromFile and GetMovieTrackCount becoming the instance methods fromFile() and getTrackCount() respectively. It does this by associating common structs and the functions that work with them into classes. QTJ lays an object-oriented API on top of the native C-based QuickTime library. The new version also neglected to provide a component to show a visual preview of the input from a capture device, such as a webcam or camcorder. This 6.1 version of QTJ also radically changed the API, so that instead of having developers create GUI components and associate Movies or other renderable objects with them, the developers now needed to start with the Movie and request a suitable component from a factory. Later that year, Apple released a new version of QTJ that dealt with the incompatibilities, by offering a compatible but scaled-down version of the GUI classes. QTJ applications could still run under Java 1.3.1, but apps that did not specify the version of Java they required, or that needed 1.4 features, were rendered unusable. The underlying problem was Apple's move from Carbon to Cocoa for their AWT implementation, and the removal of a Java-to-native library called "JDirect" that QTJ relied on. In 2003, Apple issued a Java 1.4.1 implementation that broke any QTJ applications that tried to run under 1.4.1 on Mac OS X. Later versions were installed by default with Mac OS and Mac OS X, and were an optional part of the QuickTime install for Windows. Ported to the Mac OS, it was developed under the code-name "Biscotti", and first released as a public beta in 1999. Linzmayer, in Apple Confidential 2.0, traces QuickTime for Java's genesis back to Kaleida Labs, a spin-off company created by Apple Computer and IBM, noting that it and some Unicode text classes were the only Mac software salvaged from the four-year, $150 million disaster. With this in-depth knowledge, your data- and file-management programs will be able to take advantage of every feature of Java's powerful I/O framework and much more.Owen W. This book contains unmatched coverage of Java MIO, the Stream API, the Path API, the FileVisitor API, the watch service, and asynchronous file I/O. The chapter on threads follows this up and discusses everything from the very basic concepts of a thread to the most advanced topics such as synchronizers, the fork/join framework, and atomic variables. These topics are then complemented by details of how to use lambda expressions, allowing you to build powerful and efficient Java programs. Java Language Features, Second Edition starts with a series of chapters on the essential language features provided by Java, including annotations, reflection, and generics. Author Kishori Sharan provides over 50 diagrams and 290 complete programs to help you visualize and better understand the topics covered in this book. Work with essential and advanced features of the Java programming language such as Java modules development, lambda expressions (closures), inner classes, threads, I/O, Collections, garbage collection, and more.
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