Link sources to another project is not enough to solve classes, unless you are actually compiling those sources.
A safer way to link to sources would be to define another Java project, which would link to Hive sources and compile them, then declare your HadoopDB as depending on the Hive project.
That way, HadoopDB compilation would refer to Hive .class files produced by the compilation of the Hive Java project.
A simpler way would be to find the Hive jars, and and those in the classpath dependency of your HadoopDB project.
Now I take a closer look to the HadoopDB setup, it says:
- Modify the Hive build path to link to the HadoopDB project and
- HadoopDB's build path to include both the Hive project and jar files located in
HADOOP_HOME
It does not says "link the sources".
It says "link the projects".