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Originally bundled as a separate download, Java Web Start is now included in the JRE. If you have J2SE 5.0 on your computer (or Java 1.4, on Mac OS X) then you already have Java Web Start installed and you can get started right away. While it does introduce a few new APIs (mainly for dealing with the sandbox), you can get started without writing any new code. You just need a JNLP descriptor file.

Java Web Start is a technology for deploying and updating desktop Java applications easily from a web server. It's much more than a launching protocol, however. JWS provides a sandbox for safely running applications, as well as new compression methods to speed up downloads, and some useful extensions to make your application feel at home on the user's desktop. The first part of this series covered just the basics. This second half will show you everything you need to do to make your application run safely and feel professional.

Delivering client-side Java technology-based programs has recently been a daunting task. Browser differences -- both in versions of the Java Runtime Environment (JRE) and security architecture -- have caused many developers to abandon rich client-side solutions in favor of using Java technology on the server, with JavaServer Pages (JSPTM) and servlets. But now that Java Web Start -- and the underlying Java Network Launch Protocol (JNLP) -- are a standard part of the Java 2 platform (as of version 1.4), it's far easier to deploy cross-platform, client-side systems.

The OBJECT tag detects if the machine has Java Web Start 1.2 or above installed. If it does, Java Web Start launches and handles the rest of the process (if the JNLP file specifically requests another JRE that is not available on the user's machine, Java Web Start will perform the JRE-autodownload and install). If Java Web Start 1.2 is not available, an install of the latest version of the JRE is needed before the JNLP application is launched; this install and launching is handled by the auto-installer.

Java Security Overview This paper gives a broad overview of security in the Java platform, from secure language features to the security APIs, tools, and built-in provider services, highlighting key packages and classes where applicable. (June 2005)

In this article you have seen the ease with which we can convert existing Identity Server client applications(standalone) to use the Java Web Start technique for distribution to clients. If you have developed a Java application using Remote Client API's for Sun's Identity Server and would like to serve this application to your entire corporate network accessing the central server, this would be an efficient way of distributing your application.

Recently, Java began making a comeback on the client side with technologies such as Java Plug-in and, more recently, Java Web Start. Also, the Java 2 Platform, Enterprise Edition (J2EE) incorporates technologies such as JavaServer Pages (JSP) that support desktops and a multitude of client devices by serving up HTML, XML, and so on.

Click on the link below to launch the Notepad application. If Java is not already installed on the client machine, it will automatically download and start the install of Java 5, and then after the install, it will launch the Collage Application automatically.

In the growing market of the software industry today, users are clamoring for client applications that can be run not only from a desktop environment but also from the Internet. Users want the same functionality and support from Web-based applications as they get from those on their desktop, preferably packed with a thin-client interface. The most common solution, currently, is to develop two separate Java applications: one that executes as a desktop application and one that simulates much of the functionality of a desktop application, but is accessed from the Web. This is a burden to developers, who are required to write two separate applications that perform the same on different execution environments, but it is also a financial burden to software companies, which are forced to provide support for two separate applications. To alleviate this problem, Sun Microsystems has introduced Java Web Start, a client-side technology that enables Java applications to launch either from a desktop or from a Web page. This eliminates the need to develop Java support for Web applications, and also provides an efficient means to upgrade, maintain, and manage client-side Java applications with the support of any common Web server.

Before we review the implementation details of how to deploy an SWT application using Java Web Start, let's take a look at the application we're going to deploy. The application that's included with this article is an example application provided by the Eclipse project. As shown in Figure 1, the application is a simple cross-platform file viewer that allows users to browse the files and folders on their hard drive.

This article and the second one in this series ("A JNLP Tutorial: Part 2?An Example") cover the essentials of the Java Network Launching Protocol (JNLP). They are intended for a wide audience, mainly developers, and especially those new to this technology. At the end of this tutorial, you will have a clearer idea of this Java technology, and hopefully you will be able to use it directly in your applications.

The core of the JNLP technology, as discussed in the first article, is the JNLP file. Indeed, you can have several types of JNLP files, but this article is limited to the one needed to launch applications?called the main JNLP file. Listing 1 shows the JNLP file that launches the Example class listed in the previous article.