Eclipse Not Find Classes 添加到构建路径（Java 动态 Web 项目）

Question

I am taking over a web project from my school. I am trying to deploy the project in eclipse. The project uses a group of libraries (Namely javax.mail.* , com.sun.mail.* , org.joda.* and org.apache.* ). The project can not compile because it is unable to locate these. I have them in the src folder and then added the three top level folders/packages to the build path. The import statements work. But getting the joda.time.CLASSXYZ does not work (Then I instantiate the class CLASSXYZ). (The error is "The type org.joda.time.base.BaseDateTime cannot be resolved. It is indirectly referenced from required .class files" the import was joda.time.* so the class should have been imported)

I've looked at the other threads and most of them just explain how to add folders to the build path. I have Apache tomcat set up with eclipse. It works with other projects that I have deployed.

This problem has gotten pretty frustrating as its preventing me from starting the project. Any help you be much appreciated.

Cheers

Answer 1

Unless you use maven you need to download additional libraries:

• javax.mail: http://www.oracle.com/technetwork/java/javamail/index.html (also included in Java EE)
• org.apache http://commons.apache.org/
• org.joda http://joda-time.sourceforge.net/

I suggest to place them in a folder 'lib' and add the jar-files to your build class path. (context menu on your project).

Answer 2

The other threads you mentioned are pointing you in the right direction, and provide a good practice to get in to (especially once you start having more than one project running in your eclipse ide).

So right click project - Build Path - Configure Build Path... , then in the Libraries tab, click Add External JARs and add in the jar for org.joda from the link in the other answer here. This way you can have all your external jar libraries in one spot and reuse them across multiple projects. There's also about a dozen different ways to do the same thing in eclipse, but this is the most direct I think. I'm on version Helios (your's might be slightly different). I try not to use source files of external code libraries unless I want to play around, debugging their code - not a bad thing to do - but I never have the time to spare for that.

Also I'd double check that the other libraries you mentioned aren't being automatically linked in or included as part of the JRE system library. Especially if you are setup in a Dynamic Web Project, it would surprise me if org.apache wasn't already there... but I could easily be wrong there, have been many times before & eclipse was usually involved ;-)