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I'm trying to customize my application to handle an exception throwed by webflow, the exception is SpelEvaluationException an especialization of EvaluationException. According with the documentation I implemented the interface FlowExecutionExceptionHandler and stayed like below: 

@Named
public class PerfilExceptionHandler implements FlowExecutionExceptionHandler {

private static final Logger LOGGER = LoggerFactory.getLogger(PerfilExceptionHandler.class);

@Override
public boolean canHandle(final FlowExecutionException exception) {
    return exception.getCause() instanceof EvaluationException;
}

@Override
public void handle(final FlowExecutionException exception, final RequestControlContext context) {

    LOGGER.info("handling exception {}", exception.getMessage());

    TransitionExecutingFlowExecutionExceptionHandler handler = new TransitionExecutingFlowExecutionExceptionHandler();

    handler.add(CustomException.class, "error");
}

}

Then I have been received a NullPoinerException, follows the stacktrace: 

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.NullPointerException
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:894)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:778)
javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
br.com.company.portal.web.filter.NegarAcessoSemPerfilAtivoFilter.doFilterInternal(NegarAcessoSemPerfilAtivoFilter.java:49)
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:118)
org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:84)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:113)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:103)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:113)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:45)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:183)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.jasig.cas.client.session.SingleSignOutFilter.doFilter(SingleSignOutFilter.java:65)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:87)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.access.channel.ChannelProcessingFilter.doFilter(ChannelProcessingFilter.java:144)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:192)
org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:160)
org.springframework.security.config.debug.DebugFilter.invokeWithWrappedRequest(DebugFilter.java:69)
org.springframework.security.config.debug.DebugFilter.doFilter(DebugFilter.java:58)
org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)
org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:259)
org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96

If someone can help me, I'm apreciated

Edit 1

Prasad

Follows the code:

<view-state id="perfil" view="/perfil/add">
    <on-entry>
        <set name="flowScope.urlRedirect" value="requestParameters.url"/>
        <set name="flowScope.mapSistemaPerfis" value="perfilServiceImpl.buscarSistemasComPefis(requestParameters.identificador, requestParameters.idProduto)" />
    </on-entry>

    <transition on="submit" to="savePerfil" />
    <exception-handler bean="perfilExceptionHandler"/>
</view-state>

The error occurs when an user doesn't pass the request parameters required to call method buscarSistemasComPerfis

Tks in advance

Ivan Rodrigues
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  • Hi, can you post in what scenario you are getting SpelEvaluationException because this will occur when the expression is incorrect or making a reference of incorrect field. It would be ideal to handle this scenario in first place. – Prasad Mar 19 '14 at 13:52
  • Prasad I edited the post – Ivan Rodrigues Mar 19 '14 at 14:28

2 Answers2

2

Instead of implementing FlowExecutionExceptionHandler, try extending TransitionExecutingFlowExecutionExceptionHandler like below:

public class PerfilExceptionHandler extends
        TransitionExecutingFlowExecutionExceptionHandler {

Also, you have given

handler.add(CustomException.class, "error");
  1. Have you defined target state id "error" in your webflow definition?
  2. Using add() inside TransitionExecutingFlowExecutionExceptionHandler.exposeException() method definition would be useful for identifying target state id for a particular exception.
vijay bharathy
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Ivan,

Since requestparameters is not present, when spel parser get the expression, it will see like:

     perfilServiceImpl.buscarSistemasComPefis(,);

and so you get SpelEvaluationException. The work around to handle this type of scenario is: 

<view-state id="perfil" view="/perfil/add">
<on-entry>
    <set name="flowScope.urlRedirect" value="requestParameters.url"/>
    <set name="requestScope.identificador" value="requestParameters.identificador" type="string"/>
    <set name="requestScope.idProduto" value="requestParameters.idProduto" type="string"/>
    <set name="flowScope.mapSistemaPerfis" value="perfilServiceImpl.buscarSistemasComPefis(requestScope.identificador, requestScope.idProduto)" />
</on-entry>

<transition on="submit" to="savePerfil" />
<exception-handler bean="perfilExceptionHandler"/>

This way even if requestParameters is not passed, your method receives the parameters as null values, which you can handle accordingly.

Prasad
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  • Prasad, my problem doesn't the SpelEvaluationException. I don't care with what exception will be throw, but, I care with NullPointerException when I handle the flow execution after execution of method handle(FlowExecutionException,RequestControlContext). I tested setting up the request parameters on request scope, but, the problem continues – Ivan Rodrigues Mar 19 '14 at 16:48
  • Can you check by turning on debug mode if at all the request is entering perfilServiceImpl.buscarSistemasComPefis(requestScope.identificador, requestScope.idProduto) method? – Prasad Mar 19 '14 at 17:27
  • I put in debug mode, but, I didn't see anything different. I put a breakpoint and the method perfilServiceImpl.buscarSistemasComPefis(requestScope.identificador, requestScope.idProduto) didn't called. Maybe this part can be useful handling exception Exception thrown executing [AnnotatedAction@35c86c73 targetAction = [SetAction@79480d9a name = flowScope.mapSistemaPerfis, value = perfilServiceImpl.buscarSistemasComPefis(requestScope.identificador, requestScope.idProduto)], attributes = map[[empty]]] in state 'perfil' of flow 'perfil' -- action execution attributes were 'map[[empty]]' – Ivan Rodrigues Mar 19 '14 at 19:42
  • This exception could happen in tons of ways. Remove , run the flow and then can you post the exception stacktrace, you are getting? – Prasad Mar 19 '14 at 20:55
  • @Prasad can you guide me similar issue i also have – Parameshwar Nov 03 '22 at 11:26
  • https://stackoverflow.com/questions/74301528/spring-web-flow-how-to-handle-flow-exception-org-springframework-webflow-execu is the llink – Parameshwar Nov 03 '22 at 11:26