Been setting up hsqldb to use for development in a Spring/Hibernate/WebWork2 environment. What we want is to use schemaexport, middlegen, dbunit etc. to use a generated hsqldb stored in files under the target/ directory. The web app should get a separate copy of the database included in the war file.

We solved the problem as follows (with 'templatedb' sample db):

SchemaExport and other goals use the database with a file url:
...
hibernate.connection.url=jdbc:hsqldb:target/hsqldb/templatedb
...

This way we get the database generated under the target/hsqldb directory.

Added the following goals to maven.xml, to build a jar file from the hsqldb files:

<!-- add hsqldb jar to war file -->
<postGoal name="war:webapp">
   <attainGoal name="hsqldbjar"/>
</postGoal>
<!-- goal to create hsqldb jar file -->
<goal name="hsqldbjar">
   <jar
      destfile="${maven.build.dir}/${pom.artifactId}/WEB-INF/lib/${pom.artifactId}db.jar"
      basedir="${maven.build.dir}"
      includes="hsqldb/**"/>
</goal>

This way the Spring application can use the database url with the new res: protocol:

jdbc:hsqldb:res:/hsqldb/templatedb

This is also superb for integration test cases. The database is cleaned out automatically for every testrun :)