datasource.xml

   <datasource jta="true" jndi-name="java:/Lab" pool-name="LabDS" enabled="true" use-ccm="true">
                    <connection-url>jdbc:postgresql://localhost:5432/lab</connection-url>
                    <driver-class>org.postgresql.Driver</driver-class>
                    <driver>postgresql-9.4-1201.jdbc41.jar</driver>
                    <pool>
                        <min-pool-size>1</min-pool-size>
                        <initial-pool-size>4</initial-pool-size>
                        <max-pool-size>20</max-pool-size>
                    </pool>
                    <security>
                        <user-name>postgres</user-name>
                        <password>1234</password>
                    </security>
                    <validation>
                        <valid-connection-checker class-name="org.jboss.jca.adapters.jdbc.extensions.postgres.PostgreSQLValidConnectionChecker"/>
                        <background-validation>true</background-validation>
                        <exception-sorter class-name="org.jboss.jca.adapters.jdbc.extensions.postgres.PostgreSQLExceptionSorter"/>
                    </validation>
                </datasource>