Information Center

Using Java 2

Access to Java 2 runtime (JVM) for Windows platforms


Z and I Emulator for Web Java 2 plug-in available for Windows clients

To download this Java 2 plug-in from the server, clients running on Windows should attach to dashboard.html on the server, click on IBM 32-bit Runtime Environment for Java 2, and follow the instructions.

Detecting whether the browser is using a Java 2 plug-in


Java 2 detection fails after computer is rebooted

When using Z and I Emulator for Web HTML pages on a client with the Java 2 plug-in installed, the Java 2 detection logic will sometimes indicate that Java 2 is not installed. This means that HTML pages that require Java 2 will fail, and Z and I Emulator for Web will ask if the client would like to download and install the Java 2 plug-in. For HTML pages that have the Java type set to Detect, Java 2 will not be detected, and the Java 1 JVM will be invoked.

This failure to detect Java 2 may occur immediately after installation of the plug-in or after a reboot of the computer. To resolve the problem, close and restart the browser, and then load the HTML page again.

Internet Explorer


Internet Explorer may hang when using the IBM Windows plug-in

Using the IBM Windows Plug-in, Version 1.8, if the Java Console is configured to start when the plug-in starts, Internet Explorer may hang when accessing a Z and I Emulator for Web HTML file. We recommend that you use the default configuration, which is for the Java Console not to start automatically. This is configured by an option on the Basic tab of the Java Control Panel. The Java Console can still be opened later, if needed, after the Z and I Emulator for Web applet starts.

Java 2 console


Java 2 browser Console messages during 5250 session file transfer

You may see the following message after performing a 5250 session file transfer:

Netscape security model is no longer supported.
Please migrate to the Java 2 security model instead.

You will see these messages only if your browser is running Java 2 JVM. These messages are only warnings and do not affect Z and I Emulator for Web functionality.

Netscape 6.x


Netscape 6 users must have a Java 2 plug-in installed to run Z and I Emulator for Web clients

Users wishing to use Netscape 6.x must have the Java 2 plug-in installed and enabled in order to load the Z and I Emulator for Web clients. If you choose a full Netscape 6.x installation, this plug-in is included as part of the installation. Alternatively, if you select a custom installation, then select Sun Java 2 under Additional Components.

Clients running 32-bit Windows platforms who have installed Netscape 6 without Java support can download and install a plug-in that provides Java 2 support from the dashboard.html page.

Windows platforms

Exception in Java Console on Windows machines using Windows Terminal Server or using low display resolution

On some Windows machines that use the Sun plug-in and that use either Windows Terminal Server or have a low display resolution, a NullPointerException is thrown by the class file WVolatileImage, which can be seen in the Java Console. When this happens, the user is not presented with their configured sessions. You can avoid this by setting a higher display resolution or by using the IBM 1.8 plug-in. If the HTML page has been created for the configuration server-based model, you can avoid this by adding the parameter <PARAM NAME=Bookmarking VALUE=false>.