Automatic reconnect to database for Jboss EAP 6.x/AS7.x

Jboss instance config file (standalone.xml, standalone-full-ha.xml...)

In your datasource section define background validation:

<validation>
	<check-valid-connection-sql>select 1 from dual</check-valid-connection-sql>
	<background-validation>true</background-validation>
	<validate-on-match>false</validate-on-match>
	<background-validation-millis>15000</background-validation-millis>
</validation>

Or with validate on match:

<validation>
	<check-valid-connection-sql>select 1 from dual</check-valid-connection-sql>
	<background-validation>false</background-validation>
	<validate-on-match>true</validate-on-match>
</validation>