Java Client Specific Information
The client application runs in a Java application that is downloaded to your machine. For the best performance, your machine should meet the client recommendations.
Table of Contents:
Java Web Start Applications (.jnlp)
These applications rely on OpenWebStart to launch. When you click the button, a URL of a cgi file is used to retrieve a jnlp file from the TAS. This file should be launched with OpenWebStart.
These applications are provided as jar files that can be executed directly with Java. java -jar application.jar
If Java is fully installed on your OS and associated with jar files, you could directly run the jar files from your File Explorer with the default Open:
or
Web Applications (browser/html/js)
These applications execute directly in your browser. See the homepage or Client Configuration for details on browser requirements. client recommendations.
If it is not working properly, consider the following steps:
- Clear your cache. A common hot-key for most browsers is Control-F5, which will force reload the current page, clearing the cache first.
- Make sure popup blockers allow popups for the page.
- Make sure security settings allow the page. If you get error pages about insecure page, you may need to switch browsers, or lower security settings in the browser, or whitelist the page. If your Landslide administrator has not installed an official SSL Certificate, you may have to accept warnings about Self-Signed Certificate provided out of the box by Landslide.
Saving the jnlp file launchers for our Java Web Start applications to your desktop for one-click access should be avoided. Every time the TAS is upgraded the jnlp file would need to be reloaded from the TAS, you would have to go to the homepage again, or else the application may not run properly. Instead of you saving the jnlp file, you should just turn on the OpenWebStart option to install a shortcut for you. This is available in the OpenWebStart Settings application (<OpenWebStartDir>/itw-settings.exe):
Saving Shortcuts :
When you first launch the client, you will be prompted:
This puts a special shortcut on the desktop
This shortcut will automatically download the latest JNLP file.
All Landslide Applications support Java 17, except for the Landslide Client (and the TAS Manager Console). Web Start applications must execute in a sandbox, but for Landslide Client to fully work it will need access to load local files it downloads from the TAS. Java 17 removed the ability to prompt the user to “Allow permissions” via a security manager. Now users must specifically define a policy for their apps. There are several options. In all cases, it requires a java.policy file that contains the following:
Contents of file:
grant {
permission java.io.FilePermission "${user.home}/.tas", "read,write";
permission java.io.FilePermission "${user.home}/.tas/-", "read,write";
permission java.lang.RuntimePermission "getClassLoader";
permission java.awt.AWTPermission "accessClipboard", "read,write";
permission java.awt.AWTPermission "setWindowAlwaysOnTop";
};
These permissions will allow our Clients to access just those protected directories, and allow our Clients to load libraries/files within those directories. For more information about Java security policies, see LINK.
The most ubiquitous way to get the policy applied is to create (or edit) the necessary java.policy file in the user account. This method does not require Admin privileges and should apply across all Java versions installed. Also, the same file works for both Windows and Linux, the only difference is path to the user's home directory as seen below.
WINDOWS
Create java.policy file at C:/Users/<username>/.config/icedtea-web/security/java.policy
LINUX/MAC
Create java.policy file at /home/ /.config/icedtea-web/security
A second option can isolate the settings to only one single JRE that you use to execute the clients.
For example if you have configured OpenWebStart to use this Java 17:
Just edit the java.policy for that specific JRE:
C:\Program Files\Java\jdk-17.0.2\conf\security\java.policy
And finally, you could just create your own java.policy file for Landslide and pass it into OpenWebStart via an Environment Variable which would limit this to only the executions you specifically call:
For example:
C:\Programs\OpenWebStart>set JAVA_TOOL_OPTIONS= Djava.security.policy="C:\Users\user\Documents\ls_client_policy.txt"
C:\Programs\OpenWebStart>javaws "C:\Users\user\Documents\JIRA-Confluence\tasclient.jnlp"
This logic could be defined in a special shortcut so that it would automatically apply to the JNLP file you retrieve from the Browser with a single click.
After you have configured your Java environment, close your browser windows and open a new window so that the changes can take effect, and then start the Landslide Client.
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TROUBLESHOOT: If the Landslide Client fails to start when you attempt to log in from a Windows PC, follow the steps below to resolve the problem. |
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Go to the Troubleshoot Clients page / http://TASIP/clienthelp.html. The page will open in a new window.
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Scroll down to Java Plug-in Download Links link and follow the instructions there to download and install the JRE for your operating system.
Some of the more common issues encountered are covered here.
Class file version 55.0 - When you attempt to run Landslide with an older version of Java than we support, you might get a strange error mentioning “class file version 55.0”. It might appear in many forms, but one example:
Error: A JNI error has occurred, please check your installation and try again Exception in thread "main" java.lang.UnsupportedClassVersionError: com/sseworks/sp/server/framework/SMSServer has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:756)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:473)
at java.net.URLClassLoader.access$100(URLClassLoader.java:74)
at java.net.URLClassLoader$1.run(URLClassLoader.java:369)
at java.net.URLClassLoader$1.run(URLClassLoader.java:363)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:362)
at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:352)
at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:601)
This is Java telling you that your JRE is not new enough to support the Java Application you are trying to run. Class file version 55.0 is Java 11’s class file version. Class file version 52.0 is Java 8.
A full list of the class file versions can be found here: https://javaalmanac.io/bytecode/versions/
MAC Issues
MAC issues:
FIRST request privileges (requires pw), then do update (requires username and pw). Required for basically every system setting or app update. The actual Mac update/change request will accept a pasted pw.
After you have deleted the files using either method, restart your browser and try to log in. If you are still having problems, enable the Java Console.
The console displays error messages that may be useful in troubleshooting client problems.
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Open your control panel, and the Java control. The Java Control Panel window will open.
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Select the Advanced tab.
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Expand the Java console item in the Settings list.
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Click Show Console and then click OK.
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When you attempt to log in, the Java Console window will open and display status messages and any errors encountered.
After the problem is resolved, repeat the steps above and select Hide console to return to normal operation.