Provided you have done at least one complete build you should be able to build individual modules.

1. Change to the modules home directory
   cd $GEOTOOLS_HOME/gt/modules/llibrary/main
2. Use maven to compile
   mvn compile
   It should do a complete build.
3. Use maven to update the registry
   mvn install
   It should run the test cases and install the jar in the registry for other modules (or applications).

Most Common Problem

If you have not done a full build yet then the build may fail because it can't find the jar for a module it depends on.

An error caused by not having another GT2 module installed can be a little misleading:
Error: unable to download main-2.1.x.jar

This is because Maven:

• failed to find main-2.1,x.jar in the local repository where a full build should have put it
• tried to download the file from the internet (and failed)

If you see an error like that, either do a full build or change into the module which is missing (main in this case) and type.
maven jar:install

Avoiding Tests

You may also notice that running the tests takes a fair wack of time. While these tests need to be run before you commit for the day, you may want to forgo the wait while experimenting:

maven -Dmaven.test.skip build