Recently an error determined to be caused by .jar file not being deployed to the .war file. It seems that if I define the .jar to Eclipse as an "external jar", it gets deployed.
During a migration to Java EE 5 and the newest version of Eclipse (MyEclipse), I found the .jars were predefined Java EE 5 library, so I didn't add them as external jars. With Java EE 5, the Eclipse option (formerly a check box w/J2EE 1.4) to add the files is gone. It seems as a Java EE 5 library, the .jars don't deploy to the war file.
So I'm looking at the libraries tab of my Java Build Path in Eclipse. What is the difference (when it comes to deployment) of Jars, External Jars, and Libraries? The on-line help gives no guidance. Should I expect different deployment behaviors?
The operative words there are Build Path. Eclipse itself doesn't create deployments, although you may be using a plug-in that can makes JARs, WARs, EARS, or whatever. The Build Path is simply the configuration that tells the Eclipse compiler where to find the source code and libraries used to compile with. And to specify the compiler output directory (which by default is "bin" in the project root).
An IDE is no substitute for an Intelligent Developer.