Environment variables represent a kind of placeholders, where you can store the frequently used parameters values, or strings in order not to specify them manually in the code each time they are needed. There is a number of default environment variables which are preconfigured and can be used in your application code or even adjusted before node creation to apply some customization, making your work with the platform even more convenient.
1. Tomcat, TomEE and Jetty Variables
The following workflow is pretty simple and identical for the majority of supported Java application servers, so let’s check it out first.
1. Click the Config button for your application server (Tomcat, TomEE or Jetty).
2. In the opened tab, navigate to the variables.conf file within one of the following locations. There you can see a short instruction on setting your custom environment variables.
- Tomcat, TomEE - /opt/tomcat/conf/variables.conf
- Jetty - /opt/jetty/etc/variables.conf
Follow it, by means of adding the desired custom variables here. Each variable should be either separated by a space from the next one or started from a new line.
For example:-Dvar1=value1 -Dvar2=value2
-Dmy.var3=/my/value
Do not forget to Save the configurations you have made.
3. Then make the appropriate changes in your application's code with the help of the System.getProperty("my_variable") method to appoint the specified values to the needed arguments.
For example:String var1 = System.getProperty("var1");
String var2 = System.getProperty("var2");
String var3 = System.getProperty("var3")
4. Once this is completed, Restart your application server using the corresponding button next to it.
As a result, all the newly stated configurations will be applied.
For Glassfish, variables configuration is performed through its Administration Console so the process will be the following:
- 1. Click the last button (with the gear icon) for GlassFish in your environment and choose Admin panel > Login in the appeared list (or follow the link to the Admin console that you received via email after environment creation).
2. Fill in the Username and Password fields with the credentials from the same email received earlier.
3. Once inside, choose the gfcluster-config > JVM Settings option within the Configuration’s section at the left-hand menu list.
4. Then select the JVM Options tab and click on the Add JVM Option button above the Options list. A new empty field will appear at the top of the list, wherein you can enter you custom environment variable (e.g. -Dvar1=value1).
If I’d like to call a JAR file as the option’s argument, just upload it to the home folder of your GlassFish server and specify the path to it for the desired option, for example:
-javaagent:/opt/glassfish3/temp/newrelic.jar
After all the desired parameters are set, click the Save button.
5. If everything is OK, you will get the next message:
6. Finally, switch back to your CloudJiffy dashboard and restart GlassFish using the corresponding button.
That's all. In such a way, you can manage GlassFish environment variables through the Admin Console.