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Yale and JASIG use Eclipse as the IDE. The most current version of Eclipse works best. Start with the J2EE package of Eclipse. Use the Help - Eclipse Marketplace tool to add support for Subversion (use Subversive), Maven (M2E), AspectJ (AJDT), and the add the M2E-AspectJ support from Add Software source http://dist.springsource.org/release/AJDT/configurator/. You are certainly free to add other Eclipse features for other development.
Note: As of March 2014 the M2E-AspectJ support does not work correctly. When installed, it generates a null pointer exception creating a Maven Run Configuration job. Until this is fixed, do not install it. This will mean, however, that when M2E imports the POM files it will complain that the Maven AspectJ plugin function is not support by Eclipse M2E. Ignore these messages as they have no effect on this development process.
Check Out and Build the Project
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Generally, there should only be Warning level Java messages. Note: If the M2E AspectJ support is not installed, there will be warning and error messages that the M2E component in Eclipse does not support the AspectJ Maven plugin functions referenced in the POM. Ignore these messages and any warning that the project will have resulting "build errors". This will not really be a problem.
Before the import, there was only the "cas-server" project (and the installer). The import creates an Eclipse "shadow project" (my name) for every subdirectory under cas-server that is needed. These shadow projects are Eclipse entities built from the Maven POM files. They contain Eclipse configuration and option elements (what Eclipse thinks of as the project and Build Path). What these shadow projects don't have are real source files. They contain configuration pointers the real source files in the subdirectories of the cas-server project. As you open and look at these projects, they will appear to have source. However, this source will be structured as Java Packages and Java Classes and Java Resources. This is a logical representation in Java and WAR terms of the actual source files that remain as subdirectories of the cas-source directory.
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