org.apache.struts2.interceptor
Class MessageStoreInterceptor

java.lang.Object
  org.apache.struts2.interceptor.MessageStoreInterceptor

All Implemented Interfaces:

Interceptor, Serializable

public class MessageStoreInterceptor
extends Object
implements Interceptor

An interceptor to store a ValidationAware action's messages / errors and field errors into HTTP Session, such that it will be retrieveable at a later stage. This allows the action's message / errors and field errors to be available longer that just the particular HTTP request.

In the 'STORE' mode, the interceptor will store the ValidationAware action's message / errors and field errors into HTTP session.

In the 'RETRIEVE' mode, the interceptor will retrieve the stored action's message / errors and field errors and put them back into the ValidationAware action.

In the 'AUTOMATIC' mode, the interceptor will always retrieve the stored action's message / errors and field errors and put them back into the ValidationAware action, and after Action execution, if the Result is an instance of ServletRedirectResult, the action's message / errors and field errors into automatically be stored in the HTTP session..

The interceptor does nothing in the 'NONE' mode, which is the default.

The operation mode could be switched using :-

1] Setting the iterceptor parameter eg.

   <action name="submitApplication" ...>
      <interceptor-ref name="store">
         <param name="operationMode">STORE</param>
      </interceptor-ref>
      <interceptor-ref name="defaultStack" />
      ....
   </action>
 

2] Through request parameter (allowRequestParameterSwitch must be 'true' which is the default)

   // the request will have the operation mode in 'STORE'
   http://localhost:8080/context/submitApplication.action?operationMode=STORE
 

• allowRequestParameterSwitch - To enable request parameter that could switch the operation mode of this interceptor.
• requestParameterSwitch - The request parameter that will indicate what mode this interceptor is in.
• operationMode - The operation mode this interceptor should be in (either 'STORE', 'RETRIEVE', 'AUTOMATIC', or 'NONE'). 'NONE' being the default.

The following method could be overriden :-

• getRequestOperationMode - get the operation mode of this interceptor based on the request parameters
• mergeCollection - merge two collections
• mergeMap - merge two map

 

 <action name="submitApplication" ....>
    <interceptor-ref name="store">
      <param name="operationMode">STORE</param>
    </interceptor-ref>
    <interceptor-ref name="defaultStack" />
    <result name="input" type="redirect">applicationFailed.action</result>
    <result type="dispatcher">applicationSuccess.jsp</result>
 </action>

 <action name="applicationFailed" ....>
    <interceptor-ref name="store">
       <param name="operationMode">RETRIEVE</param>
    </interceptor-ref>
    <result>applicationFailed.jsp</result>
 </action>

 
 

With the example above, 'submitApplication.action' will have the action messages / errors / field errors stored in the HTTP Session. Later when needed, (in this case, when 'applicationFailed.action' is fired, it will get the action messages / errors / field errors stored in the HTTP Session and put them back into the action.

Version:

$Date: 2008-04-27 08:41:38 -0500 (Sun, 27 Apr 2008) $ $Id: MessageStoreInterceptor.java 651946 2008-04-27 13:41:38Z apetrelli $

See Also:

Serialized Form

Field Summary

static String	actionErrorsSessionKey
static String	actionMessagesSessionKey
private boolean	allowRequestParameterSwitch
static String	AUTOMATIC_MODE
static String	fieldErrorsSessionKey
private static Logger	LOG
static String	NONE
private String	operationMode
private String	requestParameterSwitch
static String	RETRIEVE_MODE
private static long	serialVersionUID
static String	STORE_MODE

Constructor Summary

MessageStoreInterceptor()

Method Summary

protected void	after(ActionInvocation invocation, String result) Handle the storing of field errors / action messages / field errors, which is done after action invocation, and the operationMode is in 'STORE'.
protected void	before(ActionInvocation invocation) Handle the retrieving of field errors / action messages / field errors, which is done before action invocation, and the operationMode is 'RETRIEVE'.
void	destroy() Called to let an interceptor clean up any resources it has allocated.
boolean	getAllowRequestParameterSwitch()
String	getOperationModel()
protected String	getRequestOperationMode(ActionInvocation invocation) Get the operationMode through request paramter, if allowRequestParameterSwitch is 'true', else it simply returns 'NONE', meaning its neither in the 'STORE_MODE' nor 'RETRIEVE_MODE'.
String	getRequestParameterSwitch()
void	init() Called after an interceptor is created, but before any requests are processed using intercept , giving the Interceptor a chance to initialize any needed resources.
String	intercept(ActionInvocation invocation) Allows the Interceptor to do some processing on the request before and/or after the rest of the processing of the request by the ActionInvocation or to short-circuit the processing and just return a String return code.
protected Collection	mergeCollection(Collection col1, Collection col2) Merge col1 and col2 and return the composite Collection.
protected Map	mergeMap(Map map1, Map map2) Merge map1 and map2 and return the composite Map
void	setAllowRequestParameterSwitch(boolean allowRequestParameterSwitch)
void	setOperationMode(String operationMode)
void	setRequestParameterSwitch(String requestParameterSwitch)

Methods inherited from class java.lang.Object

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

Field Detail

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

LOG

private static final Logger LOG

AUTOMATIC_MODE

public static final String AUTOMATIC_MODE

See Also:

Constant Field Values

STORE_MODE

public static final String STORE_MODE

See Also:

Constant Field Values

RETRIEVE_MODE

public static final String RETRIEVE_MODE

See Also:

Constant Field Values

NONE

public static final String NONE

See Also:

Constant Field Values

allowRequestParameterSwitch

private boolean allowRequestParameterSwitch

requestParameterSwitch

private String requestParameterSwitch

operationMode

private String operationMode

fieldErrorsSessionKey

public static String fieldErrorsSessionKey

actionErrorsSessionKey

public static String actionErrorsSessionKey

actionMessagesSessionKey

public static String actionMessagesSessionKey

Constructor Detail

MessageStoreInterceptor

public MessageStoreInterceptor()

Method Detail

setAllowRequestParameterSwitch

public void setAllowRequestParameterSwitch(boolean allowRequestParameterSwitch)

getAllowRequestParameterSwitch

public boolean getAllowRequestParameterSwitch()

setRequestParameterSwitch

public void setRequestParameterSwitch(String requestParameterSwitch)

getRequestParameterSwitch

public String getRequestParameterSwitch()

setOperationMode

public void setOperationMode(String operationMode)

getOperationModel

public String getOperationModel()

destroy

public void destroy()

Description copied from interface: Interceptor

Called to let an interceptor clean up any resources it has allocated.

Specified by:

destroy in interface Interceptor

init

public void init()

Description copied from interface: Interceptor

Called after an interceptor is created, but before any requests are processed using intercept , giving the Interceptor a chance to initialize any needed resources.

Specified by:

init in interface Interceptor

intercept

public String intercept(ActionInvocation invocation)
                 throws Exception

Description copied from interface: Interceptor

Allows the Interceptor to do some processing on the request before and/or after the rest of the processing of the request by the ActionInvocation or to short-circuit the processing and just return a String return code.

Specified by:

intercept in interface Interceptor

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().

before

protected void before(ActionInvocation invocation)
               throws Exception

Handle the retrieving of field errors / action messages / field errors, which is done before action invocation, and the operationMode is 'RETRIEVE'.

Parameters:

invocation -

Throws:

Exception

after

protected void after(ActionInvocation invocation,
                     String result)
              throws Exception

Handle the storing of field errors / action messages / field errors, which is done after action invocation, and the operationMode is in 'STORE'.

Parameters:

invocation -

result -

Throws:

Exception

getRequestOperationMode

protected String getRequestOperationMode(ActionInvocation invocation)

Get the operationMode through request paramter, if allowRequestParameterSwitch is 'true', else it simply returns 'NONE', meaning its neither in the 'STORE_MODE' nor 'RETRIEVE_MODE'.

Returns:

String

mergeCollection

protected Collection mergeCollection(Collection col1,
                                     Collection col2)

Merge col1 and col2 and return the composite Collection.

Parameters:

col1 -

col2 -

Returns:

Collection

mergeMap

protected Map mergeMap(Map map1,
                       Map map2)

Merge map1 and map2 and return the composite Map

Parameters:

map1 -

map2 -

Returns:

Map