"This article talks about the Java™ Development
Tools (JDT), illustrating some commonly used features and
explaining how to customize them. It also discusses concepts and
features that may be different in the Eclipse integrated
development environment (IDE) vs. others, or features that may not
be apparent to new users of the JDT. See Part 1 if you're just
getting started with Eclipse V3.4.
"What is the JDT?
Eclipse has become synonymous with Java development. However, to
many Eclipse newcomers, the relationship between Eclipse and Java
technology may not be entirely clear.
"Eclipse is a bare-bones platform that happens to be written in
the Java programming language. Plug-ins, such as Mylar and
Findbugs, written on top of the IDE provide its functionality, and
the Java language allows Eclipse to function like a Java IDE.
Possibly because the JDT is included by default in the Eclipse
downloads, it may not be immediately clear that when developers say
they use Eclipse for Java development, what they really mean is
that they use the JDT."