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<!-- Deleted image removed: [[Image:Apple Java Web Start.png|left|80px]] -->
In [[computing]], '''Java Web Start''' is(also known as '''JavaWS''' or as '''javaws'''), a [[Software framework | framework]] developed by [[Sun Microsystems]] which, allows users to start [[application software]] for the [[Java Platform]] to be started directly from the [[Internet]] using a [[web browser]]. Unlike [[Java applet]]s, Web Start applications do not run inside the browser, and the [[sandbox (computer security)|sandbox]] in which they run doesneed not have toas be asmany restrictedrestrictions, although this can be configured. OneWeb chiefStart advantagehas ofan Web Startadvantage over applets isin that theyit overcomeovercomes many compatibility problems with browsers' Java [[plugin]]s and different [[Java virtual machine|JVM]] versions. On the other hand, Web Start programs cannot communicate with the browser as easily as applets. To assist migration, a Java Appletusers can also beinvoke useda Java Applet as a Java Web Start application.
Web Start also provides a series of classes in the <code>[http://java.sun.com/products/javawebstart/docs/javadoc/index.html javax.jnlp]</code> [[Java package|package]] which provide various services to the application. MostSun designed most of these services are designed aroundwith the ideaaim of allowing carefully controlled access to resources (such as files and the system clipboard) while restricting the application to authorized operations.
VersionSun introduced version 1.0 of Web Start was introduced by Sun in March 2001.<ref>[http://www.sun.com/smi/Press/sunflash/2001-03/sunflash.20010314.1.html Java Web Start 1.0 press release]</ref> Since [[Java 2 Platform, Standard Edition|J2SE]] version 1.4 itWeb hasStart beencomes includedas bya default withpart theof [[Java Runtime Environment]] (JRE) and doescomputer notadministrators no longer have to beinstall installedit separately.
Java Web Start is similar toresembles [[ClickOnce]] in the [[.NET Framework|.NET]] framework.
== Java Network Launching Protocol ==
Programmers often speak of the '''Java Network Launching Protocol''' ('''JNLP''') is, a closely-related concept that is often used) interchangeably with the term "Web Start"." ItThe is theJNLP protocol, defined with an [[XML]] schema, that specifies how to launch Java Web Start applications are launched. JNLP consists of a set of rules defining how exactly thisto implement the launching mechanism should be implemented. JNLP files include information such as the ___location of the [[Jar (file format)|jar]] package file and the name of the main class for the application, in addition to any other parameters for the program. With aA properly configured browser, passes JNLP files are passed to a Java Runtime Environment (JRE) which in turn downloads the application onto the user's machine and starts executing it. The development of JNLP wastook developedplace under the [[Java Community Process]] as JSR 56,. which It includes the original 1.0 release, the subsequent 1.5 maintenance release, and as of [[2006]], the pending 6.0 maintenance release. JNLP is free; developers areneed not required to pay a license fee in order to use it in programs.
Important Web Start features include the ability to automatically download and install a JRE in the case where the user does not have Java installed, and for programmers to specify which JRE version isa neededgiven toprogram runneeds ain givenorder programto execute. The user does not have to remain connected to the Internet to execute the downloaded programs, because they execute from a locally-maintained [[cache]]. Finally, automatic updatesUpdates of the software download from the Web are available when the user is connected to the Internet, thus easing the burden of deployment.
AnyoneAny cancomputer reapuser thecan benefits provided byuse JNLP by simply installing a JNLP Clientclient (most commonly Java Web Start). ThisThe Clientclient Installationinstallation can beoccur made automaticautomatically, so that the end users can see the client launcher automatically downloadeddownloading and installedinstalling before the Java application the first time they launch the latter.
JNLP works on a classic Clientclient-Serverserver scheme. The JNLP Clientclient reads and executes the JNLP Filefile (that is thean XML file) eventually contacting a JNLP Server or some web server for help. The JNLP Clientclient runs locally on the client system whereas the server is (implemented by some servlet) and is usedfunctions only for some advanced features of the protocol.
== Signed WebStart applications ==
By default, javaJava webstart applications arerun restricted, which means that they do not have access to some system resources such as local files. But youend-users can remove these restrictions by signing yourtheir webstart applications with the jarsigner tool that comes with the JDK.
== Well-known applications ==
* [[Wurm Online]] – Aa 3D Massively Multiplayer Online Fantasy Simulator.
* [[PoxNora]] – Aa [[3/4 perspective]], [[turn-based strategy]], [[collectible card game]]
* [[CrossFTP]] – Aa user friendly FTP client and server
* [[Powerschool Gradebook]] – Aa gradebook program for student scores as part of the larger Powerschool Student Information System. Replaced Powergrade.
== See also ==
* [[ClickOnce]] - Aa similar system for the [[.Net Framework]].
* [[Zero Install]] - Aa similar system which works for non-Java applications.
== References ==
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