Apache Struts 2 Documentation > Home > Guides > Core Developers Guide > Annotations > AnnotationWorkflowInterceptor
Added by Rainer Hermanns, last edited by James Holmes on Jun 18, 2008  (view change)

AnnotationWorkflowInterceptor Interceptor

Invokes any annotated methods on the action. Specifically, it supports the following annotations:

  • @Before - will be invoked before the action method. If the returned value is not null, it is returned as the action result code
  • @BeforeResult - will be invoked after the action method but before the result execution
  • @After - will be invoked after the action method and result execution

There can be multiple methods marked with the same annotations, but the order of their execution is not guaranteed. However, the annotated methods on the superclass chain are guaranteed to be invoked before the annotated method in the current class in the case of a Before annotations and after, if the annotations is After.

Examples

public class BaseAnnotatedAction {
 	protected String log = "";
<p/>
 	@Before
 	public String baseBefore() {
 		log = log + "baseBefore-";
 		return null;
 	}
 }
<p/>
 public class AnnotatedAction extends BaseAnnotatedAction {
 	@Before
 	public String before() {
 		log = log + "before";
 		return null;
 	}
<p/>
 	public String execute() {
 		log = log + "-execute";
 		return Action.SUCCESS;
 	}
<p/>
 	@BeforeResult
 	public void beforeResult() throws Exception {
 		log = log +"-beforeResult";
 	}
<p/>
 	@After
 	public void after() {
 		log = log + "-after";
 	}
 }

Configure a stack in struts.xml that replaces the PrepareInterceptor with the AnnotationWorkflowInterceptor:

<interceptor-stack name="annotatedStack">
	<interceptor-ref name="static-params"/>
	<interceptor-ref name="params"/>
	<interceptor-ref name="conversionError"/>
	<interceptor-ref name="annotationWorkflow"/>
</interceptor-stack>

Given an Action, AnnotatedAction, add a reference to the AnnotationWorkflowInterceptor interceptor.

<action name="AnnotatedAction" class="com.examples.AnnotatedAction">
   <interceptor-ref name="annotationWorkflow"/>
   <result name="success" type="freemarker">good_result.ftl</result>
</action>

With the interceptor applied and the action executed on AnnotatedAction the log instance variable will contain baseBefore-before-execute-beforeResult-after.