[[bootstrap:function]]
= Configuring the Function Service

{sdg-name} provides <<function-annotations,annotation>> support for implementing, registering and executing
{data-store-name} Functions.

{sdg-name} also provides XML namespace support for registering {data-store-name}
{x-data-store-javadoc}/org/apache/geode/cache/execute/Function.html[Functions]
for remote function execution.

See {data-store-name}'s {x-data-store-docs}/developing/function_exec/chapter_overview.html[documentation]
for more information on the Function execution framework.

{data-store-name} Functions are declared as Spring beans and must implement the `org.apache.geode.cache.execute.Function`
interface or extend `org.apache.geode.cache.execute.FunctionAdapter`.

The namespace uses a familiar pattern to declare Functions, as the following example shows:

[source,xml]
----
<gfe:function-service>
  <gfe:function>
      <bean class="example.FunctionOne"/>
      <ref bean="function2"/>
  </gfe:function>
</gfe:function-service>

<bean id="function2" class="example.FunctionTwo"/>
----
