com.opensymphony.xwork2.interceptor

Class ChainingInterceptor

java.lang.Object

com.opensymphony.xwork2.interceptor.AbstractInterceptor

com.opensymphony.xwork2.interceptor.ChainingInterceptor

All Implemented Interfaces:

Interceptor, Serializable

public class ChainingInterceptor
extends AbstractInterceptor

An interceptor that copies all the properties of every object in the value stack to the currently executing object, except for any object that implements Unchainable. A collection of optional includes and excludes may be provided to control how and which parameters are copied. Only includes or excludes may be specified. Specifying both results in undefined behavior. See the javadocs for ReflectionProvider.copy(Object, Object, java.util.Map, java.util.Collection, java.util.Collection) for more information.

Note: It is important to remember that this interceptor does nothing if there are no objects already on the stack.
This means two things:
One, you can safely apply it to all your actions without any worry of adverse affects.
Two, it is up to you to ensure an object exists in the stack prior to invoking this action. The most typical way this is done is through the use of the chain result type, which combines with this interceptor to make up the action chaining feature.

Note: By default Errors, Field errors and Message aren't copied during chaining, to change the behaviour you can specify the below three constants in struts.properties or struts.xml:

• struts.xwork.chaining.copyErrors - set to true to copy Action Errors
• struts.xwork.chaining.copyFieldErrors - set to true to copy Field Errors
• struts.xwork.chaining.copyMessages - set to true to copy Action Messages

Example:

 <constant name="struts.xwork.chaining.copyErrors" value="true"/>
 

Note: By default actionErrors and actionMessages are excluded when copping object's properties.

Interceptor parameters:

• excludes (optional) - the list of parameter names to exclude from copying (all others will be included).
• includes (optional) - the list of parameter names to include when copying (all others will be excluded).

Extending the interceptor:

There are no known extension points to this interceptor.

Example code:

 <action name="someAction" class="com.examples.SomeAction">
     <interceptor-ref name="basicStack"/>
     <result name="success" type="chain">otherAction</result>
 </action>
 

 <action name="otherAction" class="com.examples.OtherAction">
     <interceptor-ref name="chain"/>
     <interceptor-ref name="basicStack"/>
     <result name="success">good_result.ftl</result>
 </action>
 

Author:

mrdon, tm_jee ( tm_jee(at)yahoo.co.uk )

See Also:

ActionChainResult, Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected Collection<String>	excludes
protected Collection<String>	includes
protected ReflectionProvider	reflectionProvider

Constructor Summary

Constructors

Constructor and Description
ChainingInterceptor()

Method Summary

Modifier and Type	Method and Description
Collection<String>	getExcludes() Gets list of parameter names to exclude
Collection<String>	getIncludes() Gets list of parameter names to include
String	intercept(ActionInvocation invocation) Override to handle interception
void	setCopyErrors(String copyErrors)
void	setCopyFieldErrors(String copyFieldErrors)
void	setCopyMessages(String copyMessages)
void	setExcludes(String excludes) Sets the list of parameter names to exclude from copying (all others will be included).
void	setExcludesCollection(Collection<String> excludes) Sets the list of parameter names to exclude from copying (all others will be included).
void	setIncludes(String includes) Sets the list of parameter names to include when copying (all others will be excluded).
void	setIncludesCollection(Collection<String> includes) Sets the list of parameter names to include when copying (all others will be excluded).
void	setReflectionProvider(ReflectionProvider prov)

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

excludes

protected Collection<String> excludes

includes

protected Collection<String> includes

reflectionProvider

protected ReflectionProvider reflectionProvider

Constructor Detail

ChainingInterceptor

public ChainingInterceptor()

Method Detail

setReflectionProvider

public void setReflectionProvider(ReflectionProvider prov)

setCopyErrors

public void setCopyErrors(String copyErrors)

setCopyFieldErrors

public void setCopyFieldErrors(String copyFieldErrors)

setCopyMessages

public void setCopyMessages(String copyMessages)

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().

getExcludes

public Collection<String> getExcludes()

Gets list of parameter names to exclude

Returns:

the exclude list

setExcludes

public void setExcludes(String excludes)

Sets the list of parameter names to exclude from copying (all others will be included).

Parameters:

excludes - the excludes list as comma separated String

setExcludesCollection

public void setExcludesCollection(Collection<String> excludes)

Sets the list of parameter names to exclude from copying (all others will be included).

Parameters:

excludes - the excludes list

getIncludes

public Collection<String> getIncludes()

Gets list of parameter names to include

Returns:

the include list

setIncludes

public void setIncludes(String includes)

Sets the list of parameter names to include when copying (all others will be excluded).

Parameters:

includes - the includes list as comma separated String

setIncludesCollection

public void setIncludesCollection(Collection<String> includes)

Sets the list of parameter names to include when copying (all others will be excluded).

Parameters:

includes - the includes list