In order to benefit from Oracle RAC features like fault tolerance and load balancing all you have to do is configuring the connection url with the list of Oracle hosts which belongs to the cluster.
In this example we are configuring our datasource to connect to a RAC made up of host1 and host2:
<connection-url>jdbc:oracle:thin:@(description=(address_list=(load_balance=on)(failover=on)(address=(protocol=tcp)(host=host1)(port=1521))(address=(protocol=tcp)(host=host2)(port=1521)))(connect_data=(service_name=xxxxsid)(failover_mode=(type=select)(method=basic))))
</connection-url>