com.opensymphony.xwork2.interceptor
Class AliasInterceptor

java.lang.Object
  com.opensymphony.xwork2.interceptor.AbstractInterceptor
      com.opensymphony.xwork2.interceptor.AliasInterceptor

All Implemented Interfaces:

Interceptor, Serializable

public class AliasInterceptor
extends AbstractInterceptor

The aim of this Interceptor is to alias a named parameter to a different named parameter. By acting as the glue between actions sharing similiar parameters (but with different names), it can help greatly with action chaining.

Action's alias expressions should be in the form of #{ "name1" : "alias1", "name2" : "alias2" }. This means that assuming an action (or something else in the stack) has a value for the expression named name1 and the action this interceptor is applied to has a setter named alias1, alias1 will be set with the value from name1.

Interceptor parameters:

• aliasesKey (optional) - the name of the action parameter to look for the alias map (by default this is aliases).

Extending the interceptor:

This interceptor does not have any known extension points.

Example code:

 
 <action name="someAction" class="com.examples.SomeAction">
     <!-- The value for the foo parameter will be applied as if it were named bar -->
     <param name="aliases">#{ 'foo' : 'bar' }</param>

     <interceptor-ref name="alias"/>
     <interceptor-ref name="basicStack"/>
     <result name="success">good_result.ftl</result>
 </action>
 
 

Author:

Matthew Payne

See Also:

Serialized Form

Field Summary

protected String	aliasesKey
private static String	DEFAULT_ALIAS_KEY
private static Logger	log

Constructor Summary

AliasInterceptor()

Method Summary

String	intercept(ActionInvocation invocation) Override to handle interception
void	setAliasesKey(String aliasesKey) Sets the name of the action parameter to look for the alias map.

Methods inherited from class com.opensymphony.xwork2.interceptor.AbstractInterceptor

destroy, init

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

log

private static final Logger log

DEFAULT_ALIAS_KEY

private static final String DEFAULT_ALIAS_KEY

See Also:

Constant Field Values

aliasesKey

protected String aliasesKey

Constructor Detail

AliasInterceptor

public AliasInterceptor()

Method Detail

setAliasesKey

public void setAliasesKey(String aliasesKey)

Sets the name of the action parameter to look for the alias map.

Default is aliases.

Parameters:

aliasesKey - the name of the action parameter

intercept

public String intercept(ActionInvocation invocation)
                 throws Exception

Description copied from class: AbstractInterceptor

Override to handle interception

Specified by:

intercept in interface Interceptor

Specified by:

intercept in class AbstractInterceptor

Parameters:

invocation - the action invocation

Returns:

the return code, either returned from ActionInvocation.invoke(), or from the interceptor itself.

Throws:

Exception - any system-level error, as defined in Action.execute().