What is "java web start" used for?_问答_开发者

I was reading about java web start from wik开发者_开发百科i. Can someone please tell me

What is it used for?
A practical application of it; to make its use clearer.
Do other languages like C++ / C# have anything similar?

Thanks,

Roger

Java Web Start is kind of like a successor to applets - it allows Java programs to be run from your browser (though unlike applets, they don't run within the browser). For a practical example, see the TopCoder Arena.

http://www.topcoder.com/contest/arena/ContestAppletProd.jnlp

Here, Java Network Launching Protocol (JNLP) is the protocol that defines how a Web Start application should be run (analogous to HTML telling a browser how a page should be rendered).

See the Oracle tutorials:

Lesson: Web Start
Deploying a Java Web Start Application
Java Network Launch Protocol

Java Web Start software provides the power to launch full-featured applications with a single click. Users can download and launch applications, such as a complete spreadsheet program or an Internet chat client, without going through lengthy installation procedures.

With Java Web Start software, users can launch a Java application by clicking a link in a web page. The link points to a Java Network Launch Protocol (JNLP) file, which instructs Java Web Start software to download, cache, and run the application.

I'm quoting the Java Tutorial lesson on WebStart

For those of you who work with .Net something like Java Webstart is ClickOnce technology.

Java Web Start is used to write sandboxed desktop applications similar to Java Applets. Like applets they can be launched from a web browser, but they run in their own window - not inside the browser.

It runs just like a normal application, but started from clicking a web page instead of having to download and run an installer. An advantage is that it's very easy to get people who are afraid of all the security warnings to try your application. Another advantage is that you don't need to keep the browser open while you run your application. You can even install a shortcut to your application onto the user's desktop so they don't need to touch the browser at all once they have run it the first time.

The .NET equivalent is Click Once.

What is it used for?

To roll out and keep updated an application to clients. Clients need "only" a Java Runtime installed. This may be more interesting to read.

Java webstart is used to deploy/install Java applications over the network.

The alternative is to send an application (MyApp.jar) to the users who will run that directly. But if it is out-of-date, they could have collisions when the application talks to the server (for example, or other such badness).

It also allows you to package all of the required libraries. This is a HUGE benefit.

http://java.sun.com/javase/technologies/desktop/javawebstart/index.jsp

As mentioned above, it's a technology to allow you to 'push' an always up to date Java app to users. It's not often used on a consumer level, but has some adoption in a corporate atmosphere.

It's best used in somewhat controlled environments, and is especially useful to push a specific version of client software to control a server.

Do other languages like C++ / C# have anything similar?

Yes. Microsoft provides something called ClickOnce that provides a web-based installer.

Today i am looking for the same example about the Java web start... I thing this link will work for you,i have used as a beginner.

Click Here

As mention With Java Web Start software, users can launch a Java application by clicking a link in a web page. The link points to a Java Network Launch Protocol (JNLP) file, which instructs Java Web Start software to download, cache, and run the application.

We had a project, a plugin for Protégé, which is an ontology editor.

Installing the plugin isn't that hard, but to give the user a quick impression how the plugin worked, we supplied a Java Web Start application on our site. The page is still active, the plugin may have some rough edges, since it hasn't been updated for a while ... http://dac.icore.at/one/solutions.

I'm currently not aware of similar products for C/++/#.

Java web start is the 0-install solution in the java world. An application built to use Java web start (JWS) will be available as a link in a web site. This site will have the .jnlp extension. When a user clicks this link (and clicks the "execute" button of his browser) , the javaws.exe runtime will be launched. This executable will download the application and dependencies (libraries, images, and so on) and launch the application using the provided main-class of the .jnlp file).

An extensive reference of JNLP content can be found at http://lopica.sourceforge.net/ref.html

Examples of Java web start applications can be found at Swing sightings. Notice that, depending upon the chosen configuration, these applciations can also be automatically installed in start menu.