For a Tomcat installation I needed to connect to a Oracle RAC database backend.
I figured out the correct connection string, shown below:
jdbcUrl="jdbc:oracle:thin:@(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=rac01)(PORT=1521))(ADDRESS=(PROTOCOL=TCP)(HOST=rac02)(PORT=1521))(LOAD_BALANCE=on)(FAILOVER=on)(CONNECT_DATA=