I am using sparkjava as an embedded REST server. I have made the port number user configurable, however I want to handle the case where the user has specified a port that is already in use.
The error handling section of the documentation only deals with handling routes.
Is there any way to deal with errors that occur when port() is called with a port that is already in use or otherwise invalid?
My current inelegant solution is to check with a server socket before start the class that uses Spark:
try {
ServerSocket socket = new ServerSocket(prefs.getListenPort());
socket.close();
MyListener listener = new MyListener(sightingQueue, prefs.getListenPort());
} catch (Exception e) {
// port is not valid
}
From my testing, port() doesn't throw any exception when called on an already-open port. It just terminates the program. So I guess your method is the way to go, couldn't find any inherent method.
With Spark 2.6.0 you can specify an InitExceptionHandler:
initExceptionHandler((e) -> System.out.println("Uh-oh"));
There is a release candidate that you can test out:
<dependency>
<groupId>com.sparkjava</groupId>
<artifactId>spark-core</artifactId>
<version>2.6.0.RC0</version>
</dependency>`
Related
I am looking to be able to ping the MySQL server using mysql_ping() (mysqli_ping()) inside the Yii2 Framework.
I currently use the createCommand() for all my SQL queries so I do not have a good understanding of how to use the ping function outside of that scope.
I am not sure how to even grab the SQL link inside go Yii.
I do not have any test code since I am not even sure where to start.
Any help to point me in the right direction will be appreciated.
Yii DB component uses PDO, which does not have mysql_ping() equivalent. The closest what you can get is to query SELECT 1 and reconnect if exception occurred.
public function ping() {
try {
Yii::$app->db->createCommand('SELECT 1')->query();
} catch (\yii\db\Exception $exception) {
Yii::$app->db->close();
Yii::$app->db->open();
}
}
Note that reconnection implicitly may result unexpected and silent rollbacks if you're using transactions.
I am implementing Munit for a flow which involves Mule Requester. This mule requester would be picking up a file.
So, when i run the java class as Junit, it throws out an exception as, Cannot perform the operation on the FileConnector as it is stopped.
The expression used in mule requester is ,
file ://${path}?connector=FileConnector
I have also defined a global file connector.
Please let me know how to resolve this issue.
Thank you.
All connectors and inbound-endpoints are disabled by default in MUnit. This is to prevent flow accidentally processing/generating real data. (Some explanation here). For the same reason File Connector is also disabled.
To enable connectors, you need to override a method in your MUnitsuite as below -
#Override
protected boolean haveToMockMuleConnectors() {
return false;
}
For XML Munit, see this to enable connectors.
Note: This will enable and start all the connectors that you are using in your mule-configs under test. If you have SMTP connector, DB connector, MQ connector etc, they all be started during test, so use it with caution.
Check whether the file connector is defined in the files you loaded for munit.
<spring:beans>
<spring:import resource="classpath:api.xml"/>
</spring:beans>
You may also try mocking the mule requester.
I've just started digging into the new ASP.NET 5 by creating a test single page application with the OAuth login. I already know that I can use IdentityServer3 for that purpose and it seems pretty nice. I've found a post by Dominick Baier which is explaining how to set up the IdentityServer3. However, the post seems to be out of date or the identity server itself isn't working with the latest version of the ASP.NET 5 (which is beta7 at the moment).
The problem is, when I try to configure the IdentityServer in the Startup.cs I got an error from VS telling me that IApplicationBuilder has no extension method called UseIdentityServer. And this seems to be true, since in the IdentityServer3 source code they have this extension method declared for IAppBuilder (not IApplicationBuilder).
Here is my code (Startup.cs):
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
// Add MVC to the request pipeline.
app.UseMvc();
var options = new IdentityServerOptions
{
Factory = new IdentityServerServiceFactory()
};
app.UseIdentityServer(options);
}
And the error (on the last line) is
'IApplicationBuilder' does not contain a definition for 'UseIdentityServer' and the best extension method overload 'UseIdentityServerExtension.UseIdentityServer(IAppBuilder, IdentityServerOptions)' requires a receiver of type 'IAppBuilder'
Obviously, if I change the parameter type in the Configure method to IAppBuiler, it'll throw a runtime error because the dependency injection will not be able to inject that type. Even if it would, I'd lose the UseMvc() extension method.
So could you point me in the right direction please?
Perhaps I'm just missing something tiny but crucial here.
Thanks in advance!
My ejb3 application running on JBOSS6 already has a customized Exception handler "Ejbexception.java" which extends Exception class
I want to use the same to trap Exceptions with some number and send back the same to the Client Code for handling gentel message .
ex:
try{
.....
}catch(SQLException ex){
throw new EjbException("1001");
}
Now HOWto get the "1001" on the Client Code ?????
thx in advance
karthik
Did you write this Ejbexception class yourself? If so, that's a poor choice of name, because there's already a javax.ejb.EJBException in the library. However, it will work: when you throw it, the container will transport it to the client, who can then catch it. The string you inserted will be available from the exception's getMessage() method, just like normal.
If you're actually throwing a javax.ejb.EJBException here, then things are slightly different. That exception is aimed at the container, not the client. I actually don't know how it's made visible to the client. My suggestion would be to switch to using a custom exception, which the container will then pass to the client.
We are developing a proxy in WCF that will serve as a means of communication for some handhelds running our custom client application. I am curious what error handling strategies people use as I would rather not wrap EVERY proxy call in try/catch.
When I develop ASP .NET I dont catch the majority of exceptions, I leverage Application_Error in Global asax which can then log the exception, send an email, and redirect the user to a custom error landing page. What I am looking for in WCF is similar to this, except that it would allow me to pass a general faultreason to the client from a central location.
Basically I am curious how people centralize their exception handling in WCF apps.
Thanks
You might find the IErrorHandler interface useful here. We've been using this to do pretty much what you mention - centralised exception logging and providing generalised fault reasons without having to litter the code with numerous try/catches to try and deal with the problem locally.
So here is what I did. We have a few custom exceptions in our application such as BusinessRuleException and ProcessException, WCF supports both FaultException and FaultException<T>.
General practice seems to be that you always throw FaultException to the client in the case of a general error or an error that you dont want to display exactly what happened. In other cases you can pass FaultException<T> where T is a class with information about the particular exception.
I created this concept of Violations in the application, which basically meant that any custom exception had a property containing the corresponding Violation instance. This instance was then passed down to the client enabling the client to recognize when a recoverable error had occured.
This solved part of the problem, but I still wanted a general catch all that would allow me to centeralize logging. I found this by using the IErrorHandle interface and adding my own custom error handler to WCF. Here is the code:
public class ServiceHostGeneralErrorHandler : IErrorHandler
{
public void ProvideFault(Exception ex, MessageVersion version, ref Message fault)
{
if (ex is FaultException)
return;
// a general message to the client
var faultException = new FaultException("A General Error Occured");
MessageFault messageFault = faultException.CreateMessageFault();
fault = Message.CreateMessage(version, messageFault, null);
}
public bool HandleError(Exception ex)
{
// log the exception
// mark as handled
return true;
}
}
Using this method, I can convert the exception from whatever it is to something that can be easily displayed on the client while at the same time logging the real exception for the IT staff to see. So far this approach is working quite well and follows the same structure as other modules in the application.
We use the Exception Handling Application block and shield most faults from clients to avoid disclosing sensitive information, this article might be a good starting point for you, as with "best practices" - you should use what fits your domain.