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Because of the maven-enforcer problem, it is a good idea to open the pom.xml in the directory that you just created and remove the section from <plugin> to </plugin> that defines the maven-enforcer plugin. Save the file. From this point on you are on your honor to use Java 1.5 or 1.6 in your development.
As a sanity check, it is probably a good idea to go to the directory just created and, in command prompt mode, issue a "mvn install" to build the Server following the standard CAS build instructions. This gives Maven a chance to download all the dependency JAR files into your Maven repository and it tests the current POM files. If something goes wrong here then Eclipse is not involved and you should get help from the CAS lists.
Now start Eclipse, preferably with an empty workspace file the first time so it is easy to discard everything and start over if something goes wrong. In the empty Project Explorer window, right click and choose Import ... Select Maven - Existing Maven Projects. The top Root Directory box can be filled in by clicking the Browse ... button and navigating to the directory you just created when you unzipped the source.
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This may take a few minutes, longer if you have a slow internet connection. When it is done, switch back to the Java or J2EE perspective.
As a sanity check, it is probably a good idea to go to the directory just created and, in command prompt mode, issue a "mvn install" to build the Server following the standard CAS build instructions. This gives Maven a chance to download all the dependency JAR files into your Maven repository and it tests the current POM files. If something goes wrong here then Eclipse is not involved and you should get help from the CAS lists. When any external tool operates on an Eclipse workspace subdirectory, it is a good idea to do a Refresh (F5) in Eclipse so it knows about any changed files or added directories.
Delete Source Directories
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