I am using the scheduled-tasks element of the task namespace for scheduling a job.
<task:scheduled-tasks>
<task:scheduled ref="BeanA" method="retrieve" cron="${cron}"/>
</task:scheduled-tasks>
public void retrieve() throws InstantiationException,IllegalAccessException,ClassNotFoundException,SQLException{}
The method retrieve throws certain exceptions, i don't want to handle the exception in the method itself due to some requirements, How can i ascertain that the job runs even if a particular run throws an exception?
An exceptional condition is where something has gone wrong and you have to handle it if thrown exception is a checked exception but if you don't want to see boiler plate code in your calling method then you have some options like:
throw them
You can just handle later on and
throw them all
or throw as a super exception
Handle under one super exception like Exception catch clause
This way you simply print message
or re throw a new exception (may be RuntimeException) as Hibernate does.
Related
My app is a Spring Boot web application. I'm having a unique problem catching my exception with my ExceptionHandler - I think it is because the exception is being thrown and rethrown multiple times in my app flow.
Here is a high level description of the problem:
I throw ExceptionType1 in my service.
My ExceptionType1 exception is caught by my ErrorController class's error() method
#Override
#RequestMapping
public ResponseEntity<Map<String, Object>> error(HttpServletRequest request) {
boolean isErr = (boolean) request.getAttribute("filter.error");
if (isErr) {
//the error was thrown by cta filter, throw ExceptionType2
throw new ExceptionType2(errorMsg, errorCode);
} else {
//handle other errors
I catch the error, convert the ExceptionType1 exception to ExceptionType2 exception and rethrow it as ExceptionType2
The ExceptionType2 exception thrown above is caught by my ExceptionHandler class
#Component
#ControllerAdvice
public class MyExceptionHandler {
#ExceptionHandler({ExceptionType2.class})
public final String handleExceptionType2(ExceptionType2 e) throws ExceptionType3 {
throw new ExceptionType3(errorMsg, errorCode);
}
The ExceptionHandler above has an #ExceptionHandler method that catches the ExceptionType2 error thrown in the previous step, converts this exception to ExceptionType3 and rethrows it.
5. Here's my problem. There is yet another ExceptionHandler class that is supposed to catch ExceptionType3 errors - but it is not working. I put a breakpoint in my #ExceptionHandler method for ExceptionType3 and it is never hit
TLDR -- I basically catch an exception in my code - then it is
converted to another exception type and
rethrown as the new exception type 3 times in my code.
It works the first 2 times but the last time I try to convert the exception and rethrow it as ExceptionType3 - it is not caught by my ExceptionHandler class for ExceptionType3.
My theory right now is - I have converted exception type and rethrown the exception too many times. Is there some limitation on this in Spring? The reason I think this is - if I create and throw ExceptionType3 at any point in the above steps before step 5 - it is able to be caught by the appropriate ExceptionHandler class.
Any advice on this would be appreciated.
I believe that Spring does not allow handling of exceptions re-thrown from other exception handlers. Exception handler is supposed to be a final point where exception should be converted to HTTP response or just logged.
One of the way (maybe a little dirty) to solve your issue is to call handler for ExceptionType3 manually.
When optimistic locking is enabled in Hibernate, Hibernate throws a runtime exception (HibernateOptimisticLockingFailureException).
When this exception is thrown we need to catch this exception and display a meaningful message to the user. (ex. "The object is modified by someone else.")
What I am thinking to do is catching this Runtime Exception in the service level and rethrow a custom checked exception like ConcurrentObjectModificationException.
Is this the correct approch to handle this?
I have a web application in which I throw some custom exceptions(application exceptions annotated with #ApplicationException) and there is an exception mapper(provider annotated with #Provider) for each. Recently I forgot to annotate an exception with #ApplicationException and still the mapper is able to identify the exception and format the response properly.
Then I checked the documentation and I understood that the annotation will be inherited by its child class by default. So I removed the annotation from the super class and checked. The mapper still identified the exception and formatted the response.
Then I went even forward and tried throwing java.lang.IllegalArgumentException and wrote a mapper class for it. It also worked properly. Is javax.ws.rs.ext.ExceptionMapper independent of the exception being thrown. Will it not check if whether thrown exception is really annotated with #ApplicationException?
#Provider
public class IllegalArgumentExceptionMapper implements ExceptionMapper<java.lang.IllegalArgumentException> {
#Override
public Response toResponse(java.lang.IllegalArgumentException exception) {
return Response.status(Status.BAD_REQUEST).entity(exception.getMessage()).build();
}
}
Somewhere in my service class:
throw new java.lang.IllegalArgumentException("Problem with the payload. Please check the payload you are sending");
The answer is no, it will not check if whether thrown exception is really annotated with #ApplicationException.
The exception mapper is independent of the #ApplicationException.
All the exception mapper knows is, if there's no exception caught until the almost last layer, it will be processed here, if it find a matching provider.
You can also actually create a provider for RuntimeException and all exception happened in the REST request will land here (but this is not good practice, we should always throw custom exception and catch them with the provider and convert them to good error response).
When you annotate the exception with #ApplicationException you can control things like whether the transaction should be rollback, and whether it will be wrapped by EJBException etc etc.
I have heard that it is possible to log (or do something else) Exceptions with Spring in my web-App, so I don't have to manually insert in every "catch(){}" block the Log-function.
Does anyone have experience with Spring-overall-logging? I just want to get informed when an error appears
ExceptionHandler is the central point for handling unexpected Exceptions that are thrown during the Faces lifecycle. The ExceptionHandler must not be notified of any Exceptions that occur during application startup or shutdown.
See the specification prose document for the requirements for the default implementation. Exceptions may be passed to the ExceptionHandler in one of two ways:
1.)By ensuring that Exceptions are not caught, or are caught and re-thrown.
This approach allows the ExceptionHandler facility specified in section JSF.6.2 to operate on the Exception.
2.)By using the system event facility to publish an ExceptionQueuedEvent that wraps the Exception.
This approach requires manually publishing the ExceptionQueuedEvent, but allows more information about the Exception to be stored in the event. The following code is an example of how to do this.
Global Exception Handler – Exception Handling is a cross-cutting concern, it should be done for all the pointcuts in our application. We have already looked into Spring AOP and that’s why Spring provides #ControllerAdvice annotation that we can use with any class to define our global exception handler.
The handler methods in Global Controller Advice is same as Controller based exception handler methods and used when controller class is not able to handle the exception.
Sample Code
#ExceptionHandler(Exception.class)
public ModelAndView getExceptionPage(Exception e, HttpServletRequest request) {
request.setAttribute("errorMessageObject", e.toString());
return model;
}
** Here we can catch the base exception class Exception.class or any other exception class. Also we can throw and catch our own custom defines exception class.
I'm writing a stand alone application, that has to start up and be left running unattended for long periods of time. Rather than have exceptions bring it to a halt, it needs to log the exception with enough information for the support people to have an idea what happened, and carry on.
As a result each exception is wrapped in a runtime exception, then thrown to be logged by a different part of the application. I'm using aop:config tags to create an aspect to log the runtime exceptions thrown by the rest of the application. The exception would then carry on up the call stack to an UncaughtExceptionHandler to end the exception silently.
However, the same exception is being caught repeatedly, and logged (each exception is written by a separate thread, and goes to a separate log file). In the debugger, both exceptions have the same ID.
My applicationContext is basic for this :
<aop:config>
<aop:aspect ref="exceptionLoggingAspect">
<aop:after-throwing method="logException"
pointcut="execution(* *.*(..))" throwing="exception" />
</aop:aspect>
</aop:config>
The UncaughtExceptionHandler is equally basic, at least till I get it working :
private void setUncaughtExceptionHandler()
{
final Handler handler = new Handler();
Thread.setDefaultUncaughtExceptionHandler(handler);
}
class Handler implements Thread.UncaughtExceptionHandler
{
#Override
public void uncaughtException(Thread t, Throwable e)
{
System.out.println("Throwable: " + e.getMessage());
System.out.println(t.toString());
}
}
I have experimented by restricting the pointcut to a single package, and throwing an exception from that package (not the package the exception logging is in), but it is still logged twice.
Is there something fundamentally wrong with this idea ? Advice appreciated.