Exception Handling Strategy with Spring/JPA/JSF

Question

We are using JSF, Spring and JPA in our application. We are trying to simplify our Exception Handling strategy for our project.

Our application architecture is like below:

UI(JSF) --> Managed Beans --> Service --> DAO

We are using Exception Translation bean post processor for DAO layer. This is configured in Spring Application Context file.

<bean class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor" />

Where Spring wraps all database exceptions to 'org.springframework.dao.DataAccessException'. We are not doing any other exception handling in DAO Layer.

Our strategy to handle exceptions like below:

Presentation Layer:

Class PresentationManangedBean{

 try{
      serviceMethod();
   }catch(BusinessException be){
      // Mapping exception messages to show on UI
   }
   catch(Exception e){
       // Mapping exception messages to show on UI
   }

}

Service Layer

@Component("service")
Class Service{

 @Transactional(propagation = Propagation.REQUIRED, readOnly = false, rollbackFor = BusinessException.class)
 public serviceMethod(){

  try{

      daoMethod();

   }catch(DataAccessException cdae){
      throws new BusinessException(); // Our Business/Custom exception
   }
   catch(Exception e){
      throws new BusinessException();  //  Our Business/Custom exception
   }
 }

}

DAO Layer

@Repository("dao")
Class DAO{

 public daoMethod(){
  // No exception is handled
  // If any DataAccessException or RuntimeException is occurred this 
  // is thrown to ServiceLayer
 }

}

Question: We just want to confirm whether above approach is as per the best practices. If not, please suggest us the best way to handle the exceptions (playing with transaction management)?

i also want to follow this approch, but when i catch the exception and throw our custom exception, my Exception Handler not cath that excetion. Spring wrap my exception into `org.springframework.transaction.TransactionSystemException`. This is my question http://stackoverflow.com/questions/28295684/unable-to-wrap-dao-exception-in-service-layer-using-spring-mvc. How i resolve my problem? — Harmeet Singh Taara, Feb 03 '15 at 11:04

score 1 · Answer 1 · answered Feb 18 '13 at 10:46

1

This approach looks good to me.We are using same kind of approach in our project.

Vinay

answered Feb 18 '13 at 10:46

Vinay

33
3

choquero70 · Answer 2 · 2013-10-03T19:14:43.030

I use a different approach:

-I don't catch the DAE of Spring in the DAO. I let them flow up to the Controller (JSF managed bean).

-In the controller I catch any Exception (with just one "catch").

-I call a custom "handleException" method which receives the Exception caught in a parameter.

-This exception handler checks (for example,with an "if-then-else" sentence) what kind of exception is the parameter, and shows the message to the user according to that kind of exception. In my case I look for the message to show in a properties file, where the key (and the args if any) of the message are attributes of the exception (I put them there when I throw it). In particular, if you want to handle DAE in a special way, you can put an "if" branch for it in this exception handler method, and do whatever you want with it.

I think this approach is better and cleaner, because you have the exception handling in just one point, and you don't have to put so much "throws-try-catch" in every level, just in the Controller (JSF).

Of course, you can use "try-catch" in services for particular exceptions, if what you want to do in that particular case is some business logic, instead of showing a message to the user.

And also, if you don't want to deal with Spring DAE in the controller, you can wrap it into a business exception of your own and re-throw. But do this in the service layer, not in DAO.

Hope this answer helps.

score 0 · Answer 3 · answered Jun 12 '13 at 17:12

0

Your approach is very much in line with the Spring Frameworks recommendations and also avoids percolating lots of checked exceptions across the layers of your application.

answered Jun 12 '13 at 17:12

kevin mcdonnell

133
7

score 0 · Answer 4 · answered Dec 09 '14 at 14:20

0

Maybe you can seperate BusinessException and BusinessRuntimeException, Cause when you catch BusinessException throwing BusinessException but when you get Exception you still throwing same BusinessException. try to separete them. By the way why are you throw same exception when you catch BusinessException?

answered Dec 09 '14 at 14:20

erhanasikoglu

1,685
1
21
33

Thanks for the comment erhan...I will take a look and get back to you – Narendra Verma Dec 26 '14 at 04:52

score 0 · Answer 5 · answered Jan 26 '15 at 16:22

I was doing some research as I myself was confused on this. However I have a slightly different take.

Rationale is that throwing and catching exceptions at multiple layers is costly in terms of performance as well as code readability. Crux is that service method should not throw exceptions. Instead they should always a return a response which should encapsulate status, message and output entity.

However if Controller calls multiple service methods and tries to paint based on combination of responses, it can put it in a try catch block and handle exception.

With this logic, it can handle sprint mvc and rest mvc in equal measure. Let me know your thoughts.

Class PresentationManangedBean{
      try {
      Response resp1 = serviceMethod();
      if (resp1.getStatus().equals("SUCCESSFUL"))
           // handle UI painting logic.
      else
           // handle error for UI
      Response resp2 = serviceMethod2();
      if (resp.getStatus().equals("SUCCESSFUL"))
           // handle UI painting logic.
      else
           // handle error for UI
      // handle resp1 and resp2 to paint UI.  
     } catch (Exception e) {
           // handle error for UI 
     }
}

1) Service should handle all exceptions. Controller should not handle any exception. 2)

Exception Handling Strategy with Spring/JPA/JSF

5 Answers5

Linked