Updating java applet

Web Start programs are no longer an integrated part of the web page, they are independent applications that run in a separate frame. Applet launcher may not support some specific cases like loading class as resource. As of JDK9, Java applets are deprecated by Oracle with Java Web Start being the intended replacement.

Web Start can also launch unmodified applets that are packaged inside files, by writing the appropriate JNLP file. The developer prepares a special XML file with JNLP extension.

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.

The development of JNLP took place under the Java Community Process as JSR 56.

The example below gives a simple JNLP file to launch the applet, specifying code base, source, main class and window size.Only signed applications can be configured to have additional permissions.Web Start has an advantage over applets in that it overcomes many compatibility problems with browsers' Java plugins and different JVM versions.Updates of the software download from the Web and become available when the user has a connection to the Internet, thus easing the burden of deployment.Any computer user can use JNLP simply by installing a JNLP client (most commonly Java Web Start).

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