Want to implement the exceptional handling for errors and exceptions,how to achieve it? is there any document for this?
I search on this but I haven't find any official documentation for this.
Related
I'm a bit confused...
I have a webapp exposing soap webservices.
Now I need my ws's clients to get exception my ws methods are generating (custom exceptions and generic exceptions like Hibernate Exception and so on).
I read a lot but I can't figure out a good solution for... can you please indicate me the best way for this?
I've seen a lot of code in Sitecore where Assert.IsNull is used before any logic;
e.g.
Database database = Factory.GetDatabase(itemUri.DatabaseName);
Assert.IsNotNull(database, itemUri.DatabaseName);
return database.GetItem(attribute);
Could someone help me understand why I would use this?
This topic isn't really specific to Sitecore, even though in this case the assert methods are within the Sitecore library.
In general, assertions are used to ensure your code is correct during development, and exception handling makes sure your code copes in unpredictable circumstances.
Take a look at these SO questions for some very good explanations.
When to use an assertion and when to use an exception
When to use assert() and when to use try catch?
Here's an article specifically about the use of Sitecore assertions:
http://briancaos.wordpress.com/2012/01/20/sitecore-diagnostics-assert-statements/
We know that CGLIB provides several Callback implementations, with the most useful one of MethodInterceptor. However, how about other ones(FixedValue, Dispatcher, LazyLoader, NoOp, ProxyRefDispatcher) ? I browse the API document but can not get useful information. Can anyone show how and when to use these Callbacks in what scenarios ? I read the related code in Spring but I am still puzzled.
Thanks!
I wrote a summary of all callbacks (and more) in this blog article:
http://mydailyjava.blogspot.no/2013/11/cglib-missing-manual.html
Background
The book The Joy of Clojure explains how JVM exceptions are a closed system and suggests that there may be better alternatives for reporting and handling errors in clojure. From my experience, the common lisp condition system seems ideal, however, I am not restricting answers to this paradigm. From what I've researched there are conditions (Gilardi) http://clojure.github.com/clojure-contrib/condition-api.html , error-kit (Chouser) http://richhickey.github.com/clojure-contrib/error-kit-api.html, and handler (Weiss) https://gist.github.com/745223, however there does not appear to be a clear winner among these implementations and I feel more information on topic would be useful.
How have existing alternatives been successfully used in projects? I'm looking for examples to emulate.
How do these alternative systems overcome limitations with the JVM exception system?
What are the future directions or what are experimental alternatives on the horizon and what they entail?
FYI, this is being discussed in clojure-dev. Ideas collecting here and thread here.
Many years have passed since the question was asked, but I think the topic is still relevant. I have been working on Promenade (see documentation) that can express error as data and provides elegant error handling and control flow. There are also other projects (mentioned on Promenade README) trying to address the same issue.
Does anyone know of a program or plug-in or anything that I can find out what are all the exceptions any method may throw?
I think JAVA has this build in if I'm not mistaken. Where the compiler tells you what exceptions this method will throw.
Does the same exist for .NET?
Thanks
Edit: After searching around more, I wish there was tool like Object Explorer, except for Exceptions. You select the class or method and it lists the exceptions, at that level, which are thrown by the class. The tool links provided are a great start. Thanks!
I don't know if this is exactly what you are looking for, but:
http://www.red-gate.com/Products/Exception_Hunter/index.htm
Note: I've never used the product, and I don't work for Red Gate, I just remember seeing it advertised before.
You can see this information with intellisense in Visual Studio. When you highlight a method name in the intellisense list, its description should contain a list of exceptions at the bottom. This information is added by properly commenting your methods and classes. If you are using a library that is not part of the framework, then you will only get this information if the developers of the library appropriately commented their code.
.NET doesn't require or permit each method to state which exceptions it throws. As I recall, it was felt that this would lead most developers to simply state "throws Exception".