Chapter 18. Recommendations for transformations developers

Add external libraries to app-server classpath

i.e. connections (JDBC/JMS) may require third party libraries. It is strongly recommended to add these libraries to app-server classpath.

CloverETL allows you to specify these libraries directly in graph definition so CloverETL may load these libraries dynamically, but external libraries may cause memory leak resulting with "java.lang.OutOfMemoryError: PermGen space" in this case.

In addition, app-servers should have the JMS API on their classpath and the third-party libraries often bundle this API as well. So it may result in classloading conflicts if these libraries are not loaded by the same classloader.

Another graphs executed by RunGraph component may be executed only in the same JVM instance

In server environment, all graphs are executed in the same VM instance. Attribute "same instance" of RunGraph component cannot be set to false.