[jbosscache-commits] JBoss Cache SVN: r7103 - core/trunk/src/main/docbook/faq/en.

Author: manik.surtani(a)jboss.com Date: 2008-11-10 06:45:23 -0500 (Mon, 10 Nov 2008) New Revision: 7103 Modified: core/trunk/src/main/docbook/faq/en/master.xml Log: Added FAQ on SELECT FOR UPDATE Modified: core/trunk/src/main/docbook/faq/en/master.xml =================================================================== --- core/trunk/src/main/docbook/faq/en/master.xml 2008-11-10 11:39:16 UTC (rev 7102) +++ core/trunk/src/main/docbook/faq/en/master.xml 2008-11-10 11:45:23 UTC (rev 7103) @@ -776,6 +776,36 @@ </answer> </qandaentry> + <qandaentry> + <question> + <para> + Does JBoss Cache support <literal>SELECT FOR UPDATE</literal> semantics? + </para> + </question> + + <answer> + <para> + Yes, but this is is only possible if you are running within a JTA transaction <emphasis>and</emphasis> + are using either <literal>MVCC</literal> or <literal>PESSIMISTIC</literal> as your node locking scheme. + </para> + <para> + To achieve <literal>SELECT FOR UPDATE</literal> semantics, simply do: + </para> + <programlisting role="JAVA"><![CDATA[ + + // start transaction ... + + cache.getInvocationContext().getOptionOverrides().setForceWriteLock(true); + Node n = cache.get("/a/b/c"); // this acquires a WRITE LOCK on this node + ... + ... + + // end transaction + + ]]></programlisting> + </answer> + </qandaentry> + <qandaentry> <question> <para>With replication (REPL_SYNC/REPL_ASYNC) or invalidation (INVALIDATION_SYNC/INVALIDATION_ASYNC), how