What is Java Sound?

The Java Sound API specifies mechanisms for capturing, processing, and playing back audio and MIDI (Musical Instrument Digital Interface) data in a framework that promotes extensibility and flexibility.

Sun's reference implementation for the Java Sound API, also known as the Java Sound engine, is a 64 channel audio rendering and MIDI controlled sound synthesis engine which offers reliable, high quality sound on all Java 2 Platforms. This implementation also supports a set of high-quality General MIDI sound banks.

Who needs Java Sound?

Anyone who is interested in adding sound capabilities into their Java applets and applications will benefit from the Java Sound API. Java Sound will enable a wide variety of markets, such as education, advertising and telecommunications, to take advantage of its high quality audio to make communication more effective and accessible.

Where is Java Sound available?

The full featured Java Sound API is available as a core API in the Java 2 SDK, Standard Edition, v. 1.3 and above. The full featured Java Sound API is also available as part of the Java Media Framework 2.x for use on older JDK 1.x platforms.

Please note that the Java 2 Runtime Environment, Standard Edition, v. 1.3 release for Win32 does not include a soundbank. To use the software synthesizer with this release bundle, you must manually install a soundbank. For more information, refer to the Soundbanks page.

This API provides comprehensive access to the features of the Java Sound engine, and allows musicians and sound designers to integrate their work into Java applets and applications.

The Java Sound engine has been integrated into previous releases of the Java 2 platform (formerly known as JDK 1.2), and uses the existing AudioClip interface to access it. This means AudioClips may be created from any of the supported file formats using any of the supported data types.

What are the benefits of Java Sound?

Consistent and Reliable Sound:
Java Sound allows consistent, reliable, high-quality audio on all Java-enabled platforms. Developers have the assurance their audio content will sound great across all platforms, with the only requirement being a simple digital to audio converter (DAC).

CPU Efficient:
Java Sound uses only a small amount of a system's CPU to process sound files. For example: a 24-voice MIDI file uses only 20% of the CPU on a Pentium 90 MHz system.

Complete Audio API:
The fully featured Java Sound API allows total access to the underlying synthesis and rendering engine. This provides musicians with the capability to create new musical instruments and engineers the ability to capture microphone data for telephony or audio conferencing applications.

What audio formats does Java Sound support?

Java Sound supports the following audio file formats: AIFF, AU and WAV. It also supports the following MIDI based song file formats: SMF type 0 (Standard MIDI File, aka .mid files), SMF type 1 and RMF.

The Java Sound engine can render 8 or 16 bit audio data, in mono or stereo, with sample rates from 8KHz to 48KHz, that might be found in streaming audio or any of the supported file formats.

How do you stream audio using Java Sound?

Java Sound can begin playing as soon as it starts getting audio samples or MIDI requests -- there is no need to wait for the entire audio file to be loaded into memory.

Java Sound can be used in conjunction with the Java Media Framework API software (JMF) to stream audio data over the network. Third parties can also use Java Sound to present audio within their own streaming framework.

What other APIs that Sun is creating that relate to Java Sound?

Java Sound is part of a family of APIs that work together to provide customers with enhanced multimedia capabilities.

These APIs include:

Java 2D - two dimensional graphics and imaging
Java 3D - three dimensional graphics and imaging
Java Advanced Imaging - additional graphics and imaging operations which extend Java 2D
Java Media Framework - allows the capture, streaming and playback of time-based media such as audio and video.
Java Shared Data Toolkit - provides collaboration support for Java applets and applications.
Java Speech - speech synthesis and recognition (API only)
FreeTTS free speech synthesizer in Java - speech synthesis (implementation only)

What's New in the Sun Java Wireless Toolkit 2.3 beta

The Sun Java Wireless Toolkit just keeps getting better. Version 2.3 beta adds support for three new APIs:

• The Security and Trust Services APIs (SATSA, JSR 177) allow MIDlets to communicate with smard cards and perform cryptographic functions.
• The Location API (JSR 179) gives MIDlets a way to discover the current location of the device.
• The Content Handler API (CHAPI, JSR 211) provides a mechanism for launching MIDlets based on the type of content a device receives.

Product Description Sun Certified Enterprise Architect for J2EE Technology  (SCEA  310-051)

The Sun Certified Enterprise Architect for J2EE Technology (Step 1 of 3) certification exam is for enterprise architects responsible for architecting and designing Java 2 Platform, Enterprise Edition (J2EE) compliant applications, which are scalable, flexible and highly secure.

DETAILS

Delivered at: Authorized Prometric testing centers Prerequisites: None Other exams/assignments required for this certification: Step 2 (CX-310-300A), Step 3 (CX-310-061) Exam type: Multiple choice, short answer, and drag and drop Number of questions: 48 Pass score: 68% Time limit: 75 minutes
RECOMMENDED TRAINING

To succeed fully in this exam, candidates can take advantage of the following course(s):
SUPPORTING COURSES

Developing J2EE Compliant Applications (FJ-310)
Architecting and Designing J2EE Applications (SL-425)

Exam Objectives of Java Collections Framework  for Sun Certified Programmer for Java 2 Platform 1.4 (CX-310-035)

• Make appropriate selection of collection classes/interfaces to suit specified behavior requirements.
• Distinguish between correct and incorrect implementations of hashcode methods.

Terms you'll need to understand of Java Collections Framework for Sun Certified Programmer for Java 2 Platform 1.4 (CX-310-035)

• Enumeration
• Collection
• Set
• List
• Map
• Iterator
• Sorted
• Ordered

Java thread overview

A thread is similar to the sequential programs described previously. A single thread also has a beginning, a sequence, and an end. At any given time during the runtime of the thread, there is a single point of execution. However, a thread itself is not a program; it cannot run on its own. Rather a thread runs within a program. The following figure shows this relationship.

The reason we need thread is that  many programs, of any size, contain some code segments that are more or less independent of one another, and that may execute more efficiently if the code segments could be overlapped in time. Threads provide a way to do this. Of course, if like most people your computer only has one processor, you can't execute more than one computation at any instant, but you can overlap input/output operations with processing.

Here are some thread examples:

E-mail programs don’t make you wait for all your messages to download
before you can read the first message. Instead, these programs use separate threads to display and download messages.

The Java Virtual Machine itself uses threading for some of its housekeeping chores. For example, the garbage collector runs as a separate thread so it can constantly monitor the state of the VM’s memory and decide when it needs to remove objects that are no longer being used to create some free memory.