public class PrepareInterceptor extends MethodFilterInterceptor
prepare() on actions which implement
Preparable. This interceptor is very useful for any situation where
you need to ensure some logic runs before the actual execute method runs.
A typical use of this is to run some logic to load an object from the database so that when parameters are set they can be set on this object. For example, suppose you have a User object with two properties: id and name. Provided that the params interceptor is called twice (once before and once after this interceptor), you can load the User object using the id property, and then when the second params interceptor is called the parameter user.name will be set, as desired, on the actual object loaded from the database. See the example for more info.
Note: Since XWork 2.0.2, this interceptor extends MethodFilterInterceptor, therefore being
able to deal with excludeMethods / includeMethods parameters. See [Workflow Interceptor]
(class DefaultWorkflowInterceptor) for documentation and examples on how to use this feature.
Update: Added logic to execute a prepare{MethodName} and conditionally
the a general prepare() Method, depending on the 'alwaysInvokePrepare' parameter/property
which is by default true. This allows us to run some logic based on the method
name we specify in the ActionProxy. For example, you can specify a
prepareInput() method that will be run before the invocation of the input method.
Interceptor parameters:
Extending the interceptor:
There are no known extension points to this interceptor.Example code:
<!-- Calls the params interceptor twice, allowing you to
pre-load data for the second time parameters are set -->
<action name="someAction" class="com.examples.SomeAction">
<interceptor-ref name="params"/>
<interceptor-ref name="prepare"/>
<interceptor-ref name="basicStack"/>
<result name="success">good_result.ftl</result>
</action>
Preparable,
Serialized FormexcludeMethods, includeMethods| Constructor and Description |
|---|
PrepareInterceptor() |
| Modifier and Type | Method and Description |
|---|---|
String |
doIntercept(ActionInvocation invocation)
Subclasses must override to implement the interceptor logic.
|
void |
setAlwaysInvokePrepare(String alwaysInvokePrepare)
Sets if the
prepare method should always be executed. |
void |
setFirstCallPrepareDo(String firstCallPrepareDo)
Sets if the
prepareDoXXX method should be called first |
applyInterceptor, getExcludeMethodsSet, getIncludeMethodsSet, intercept, setExcludeMethods, setIncludeMethodsdestroy, initpublic void setAlwaysInvokePrepare(String alwaysInvokePrepare)
prepare method should always be executed.
Default is true.
alwaysInvokePrepare - if prepare should always be executed or not.public void setFirstCallPrepareDo(String firstCallPrepareDo)
prepareDoXXX method should be called first
Default is false for backward compatibility
firstCallPrepareDo - if prepareDoXXX should be called firstpublic String doIntercept(ActionInvocation invocation) throws Exception
MethodFilterInterceptordoIntercept in class MethodFilterInterceptorinvocation - the action invocationException - in case of any errorsCopyright © 2000–2020 Apache Software Foundation. All rights reserved.