JDT Core (org.eclipse.jdt.core) is the plug-in that defines the core Java elements and API. You should always list this plug-in as a prerequisite when you are developing Java specific features.
JDT Core packages give you access to the Java model objects and headless Java IDE infrastructure. The JDT Core packages include:
org.eclipse.jdt.core.jdom is deprecated since version 3.0.
The manipulation of the structure of a compilation unit should be done using