What is the best way to launch HSQLDB for unit testing, when working with spring, maven and hibernate?

I am assuming that with hsql you are referring to HSQLDB.

Configure your database url for JDBC drivers (for hibernate etc) to embedded memory based version of HSQLDB:

jdbc:hsqldb:mem:myunittests

Then a inprocess version of HSQLDB automatically starts that stores stuff to memory. No need to start any external servers.

I myself use in-memory database of hsql for testing my DAO. As a result, I need not be connected to any external db server or have any network connection.
Use following settings:

jdbc.driverClassName=org.hsqldb.jdbc.JDBCDriver

jdbc.url=jdbc:hsqldb:mem:DatabaseName

Also include the

<property name="hibernateProperties">   <props>     <prop key="hibernate.dialect">org.hibernate.dialect.HSQLDialect</prop>     <prop key="default_schema">test</prop>     <prop key="hibernate.show_sql">true</prop>     <prop key="hibernate.format_sql">false</prop>     <prop key="hibernate.hbm2ddl.auto">create</prop>   </props></property>

This will allow you to use the in-memory database and will automatically create the database tables from hibernate objects before executing tests.

Hope this will help you.

Note:

The "default_schema" property is used when your DBA creates multiple schemas within a single database. I've seen this with postgres where everyone uses one database URL but under that there are separate schemas for each application.

By using the default schema property it allows you to keep the schema names off your entities. This is particularly useful if you're running tests against HSqlDB which does not support schemas and you deploy against a DB that is using schemas. Having a null value just means it defaults back to the DB default schema.

You can also run an Ant task <startdb>:

https://forums.hibernate.org/viewtopic.php?f=6&t=984383&start=0