Library JAR projects and including them in other projects
It is a very common practice to create library projects whose final output is a JAR, and then to include those JARs in other projects (like a Web project).
In Eclipse I found it easy to create those projects and even setup dependencies so that compilation happens correctly. But I have not found an easy way to:
(a) Make the library project automatically generate the JAR. I have been able to manually create a JAR by Exporting from a Java project, but it is a hassle when you are in a rapid enhance/rebuild/test cycle.
(b) Tell a Web project to automatically include the library JAR from the other project into WEB-INF/lib during deployment.
This was trivial in Netbeans because of its Ant-based build mechanism. I presume that even without switching to Ant builds in Eclipse it is probably still trivial... so, how do you do it?