And we are NOT talking about JAVA
applets here...
Why Not Deploy your applications as
Applets
Well there are lots of reasons you don't want to use applets..(however simple writing 'em...)...to list a few...
1. JRE specific
Some Applets are JRE specific...you
definitely don't want to design your applications for a Specific JRE...
2. Manual download needed if your
browser doesn't have JAVA
Some browsers, notably mobile
browsers running Apple iOS or Android do not run Java applets
at all...You definitely can't assume every browser would have JRE.
3. No Well-defined standard
There is no standard to make the content of applets available to screen readers. Therefore, applets can harm the accessibility of a web site to users with special needs.
4. Cross Browser compatibility issues
Web Start has an advantage over applets in that it overcomes many compatibility problems with browsers' Java plugins and different JVM versions.
And thankfully Sun did address these issues by bringing a new,flexible and robust deployment solution for Java technology-based applications...and that is JAVAWS(not to be confused with JAVA Web Services)...It is JAVA Web Start.
What's JWS
JavaWS is a framework which allows users to start application software for the Java Platform directly from the Internet using a web browser.
Why Java Web Start over Applets:
1. Auto-download of Software from java.sun.com
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A main feature of the
Java Network Launching Protocol and API technology is the ability to
automatically download and install Java Runtime Environments onto the users
machine.
For example, an
application might depend APIs in Sun's Java Runtime Environment 1.4.0 (or
later). When a user first accesses this application, the Java Web Start
software will download all the needed files for the application, as well as
download the Java Runtime Environment (JRE) if the requested version is not
available locally. The ability to automatically download a JRE is one aof the
key features to ensure robust deployments. It ensures that the JRE that your
application is tested on will be available on the user's machine, as well as
make it possible to seamlessly upgrade to improved versions of the Java 2
platform over time.
2. Eliminates Cross-Browser compatibility issues
Web Start has an
advantage over applets in that it overcomes many compatibility problems with
browsers' Java plugins and different JVM versions. On the
other hand, Web Start programs are no longer part of the web page. They are
independent applications that run in a separate frame.
3. Security
By default, Java Web
Start applications run "restricted", which means that they do not
have access to some system resources such as local files. But publishers can
remove these restrictions by signing their Web Start applications with
the jarsigner tool that comes with the JDK.
How to Implement
The JWS is often termed
similar to JNLP(JAVA Network Launcher Protocol), defined with an XML schema,
specifies how to launch Java Web Start applications. JNLP consists of a set of
rules defining how exactly to implement the launching mechanism. JNLP files
include information such as the location of the jar package file and
the name of the main class for the application, in addition to any other
parameters for the program. A properly configured browser passes JNLP files to
a Java Runtime Environment (JRE) which in turn downloads the application onto
the user's machine and starts executing it.
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