Informing the IBM Community

What JDK 9 means for your Terminal Emulator


What is JDK 9 and why does it matter?

JDK stands for the Java Development Kit and the 9 refers to the version of it which was released on September 21st 2017. Oracle have stated that as JDK 9’s September release they will be removing support for the Java Applet and WebStart functionality, including the Applet API, The Java plug-in, the Java Applet Viewer, JNLP and Java Web Start including the javaws tool. This means that Applets and plugins which were once widely useable will no longer be supported by JDK. This will impact numerous users in the terminal emulation market, especially those not using a pure HTML web based emulator.



People have traditionally used Java Applets (or other plug-ins) to provide terminal emulators in a browser for several reasons.

  • The vendor already has a desktop terminal emulator which they could convert into a Java Applet for the web.
  • It is a lot easier to develop a terminal emulator in Java than it is in pure web technologies.
  • It is hard to develop a terminal emulator in pure web technologies that performs as well and has as many features as a Java Applet or desktop emulator. Despite this, we at Flynet have managed to produce a premium desktop emulator which performs well and only uses pure web technologies.


Java Applet

The Java Applet is one such mechanism whereby a java application can be run inside a web browser. This is how IBM currently displays their HOD terminal emulator inside the web browser. Web browsers traditionally allowed third parties to extend their functionality using “plug-ins”. Oracle used this plug-in functionality to create the Java Applet. The socket used to plug the Java applet into a web browser is called “NPAPI”. NPAPI (Netscape Plugin Application Programming Interface), this is also being removed (or deprecated) by most (if not all) the major browser vendors.

The removal of NPAPI, and the fact that it is no longer “fashionable” or possible to use plug-ins, has been the final death knell for Java Applets.


Java Webstart

IBM HOD’s “fix” for the removal of applets has been to move to WebStart, which has also been deprecated.

Java WebStart is another way of delivering web applications via the browser. Instead of running the java application inside the browser, it facilitates the downloading of the application to your local computer, and the launching of that application. The way it works in practice (and with IBM HOD), is that you go to a web page, it launches a download window to install the app locally, and then it is launched. If you revisit the web page, it can detect that you already have the application locally, and it will simply launch it instead of downloading it again.

This method has also been deprecated by Oracle in Java 9 and will vanish in future versions.


Pure Web Solution

There are other plug-in technologies, Activ X for example, most of which are also being depreciated. Pure web solutions like Flynet Viewer TE use web native technologies (HTML and JavaScript), and therefore like any other sophisticated web site they are the obvious choice to replace the somewhat bulky, by comparison, and now defunct plug in based solutions.

The major reason that plug-ins are no longer fashionable is they are not secure, as the vendors retract their support and interest, the list of security breach points grows.  For most organisations using emulators, they are connecting to business critical components of their ERP’s and therefore employing technology with known security exposures is not acceptable.

How does Flynet fit into this? Flynet’s suite of products do not not use Java Applets, NPAPI plug-ins, or any other sort of plug-in. Instead, Flynet uses pure web standard technologies: HTML and JavaScript. Flynet Viewer TE is used by banks, insurers and retailers world wide and has been penetration tested by KPMG, giving you the peace of mind that you can securely access your critical business system anytime, anywhere and on any device without the need for client side software.

Worried about JDK9 and how it might impact your business? Contact Flynet at ( to arrange your free JDK 9 consultation today.


How useful was this post?

Click on a star to rate it!

Average rating 0 / 5. Vote count: 0

No votes so far! Be the first to rate this post.