An exception is an occurrence in an application process that requires deviation from the program's normal flow.

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1answer
279 views

Separate namespace just for exceptions?

I was doing a code review and came across something odd which I've never seen before. The developer decided to create a sub-namespace just to contain all the assembly's exceptions. I thought I had ...
3
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2answers
179 views

Is it an acceptable practice to Get a property, that involve parsing binary, that might throw an exception?

I have a property that is loaded lazily, any time after the ctor is called. It is possible that the binary that my property relies on is invalid. If invalid I might have to throw an exception. ...
10
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2answers
3k views

Is it conventional to raise a NotImplementedError for methods whose implementation is pending, but not planned to be abstract?

I like to raise a NotImplementedError for any method that I want to implement, but where I haven't gotten around to doing it yet. I might already have a partial implementation, but prepend it with ...
1
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1answer
55 views

Partial recovery from an Exception [duplicate]

I have seen Exception Handling blocks that they were throwing the recently caught Exception in the catch block. Something like: } catch ( Exception $e ) { // Do some recovery here ...
3
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1answer
108 views

Exceptions catching clutter code and make it hard to read

When I read well written code that checks to make sure all the input is of the correct format and type, and also catches all the things that possibly could go wrong, I find it difficult to understand ...
19
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2answers
1k views

What is the advantage of wrapping exceptions [duplicate]

It's very common in .NET for an exception to be wrapped in several layers of "outer exceptions" which give marginally more contextual data. For example, in EF if your update fails, you get exceptions ...
2
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2answers
639 views

Doing work in vector's push back

I often use the following syntax: std::vector<foo> vec; vec.push_back( someClass.getFoo(...).modifyAndReturn() ); Considered about exception safety, I quote the standard on vector's push back ...
3
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1answer
140 views

Etymology of “throw an exception“ [closed]

Why do we use the expression “throw an exception“ and not something like “generate“? Where was that term born and in which language?
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3answers
256 views

C API in C++ with RAII, two alternatives to implement error handling (Exceptions)

I have an API written in C, which produces a result by returning a pointer to allocated memory. For using it with C++ (C++11) I've wrapped the function calls in objects, which keep the result in a ...
18
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2answers
2k views

Workaround for Java checked exceptions

I appreciate a lot the new Java 8 features about lambdas and default methods interfaces. Yet, I still get bored with checked exceptions. For instance, if I just want to list all the visible fields of ...
0
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5answers
249 views

Fail-fast paradigm overheads

Fail-fast seems like a right way since it simplifies bug detection. But it's a harm for performance cause of multiple checking the same thing at several levels of the system. Simple example. There is ...
3
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2answers
125 views

Inform caller or just let them deal with exception?

I'm not sure how to proceed in the following situation. say we have a function as so: def runsATask(codes): myDicts = [helperFunc(code) for code in codes] for item in myDicts: # some ...
3
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3answers
280 views

Does Exception Handling Violates “Program to Abstraction”? [duplicate]

I am talking based on experience with Java and C#. I do not know if other language have different exception handling implementation. In order to achieve loose coupling, we need our code being ...
2
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1answer
130 views

How to handle when one user deletes the object while the other has it opened in edit mode in a webapp?

I am developing a CRUD type web application. It is a project management system having projects, milestones, tasks, employees etc. Each employee has his/her own account to login and view the system. ...
0
votes
1answer
226 views

Either Monad and Exceptional Circumstances [duplicate]

I have a function returning an Either such as GetUserFromDb(int id). If the database is offline, should I catch the error in the function and wrap it in a failure / Left case or should I let it ...
9
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4answers
878 views

When and how should I use exceptions?

The Setting I often have trouble determining when and how to use exceptions. Let's consider a simple example: suppose I am scraping a webpage, say "http://www.abevigoda.com/", to determine if Abe ...
0
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2answers
416 views

Is storing stack traces in database recommended?

The current system I am working on goes through a set of documents & performs some logic using the metadata of the document. If the metadata of a document is fishy..it throws an exception. The ...
3
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2answers
207 views

Understanding exceptional cases

I've been studying the use of exceptions in various php projects (such as Doctrine and Zend Framework). Exceptions seem to be thrown when unordinary input/state occurs. A perfect example is Doctrine ...
5
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4answers
724 views

What's the reason exceptions are heavily used in managed (C# and Java) languages but not in C++? [closed]

AFAIK, a lot of C++ projects don't allow exceptions and deny them in coding guidelines. I have a lot of reasons, for example, exception is hard to handle correctly if your binary needs to be compiled ...
2
votes
3answers
494 views

Layering Design Pattern in Java clean code style

As a Java developer, I am developing trying to use the clean code rules. But in my team we are facing a concrete problem: We have a business layer offering a service called "createObject", this ...
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4answers
570 views

What's the difference between the code inside a finally clause and the code located after catch clause?

My java code is just like below: public void check()throws MissingParamException{ ...... } public static void main(){ PrintWriter out = response.getWriter(); try { check(); } ...
3
votes
3answers
228 views

Throwing exception from a property when my object state is invalid [duplicate]

I am aware that for the general case, the answer to "should I throw an exception from a property" is "generally don't, but in some special circumstances it is OK to do so". There is a Microsoft ...
2
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3answers
376 views

What code lays behind C++ exception?

In C and C++ you can return a single variable inside a function. Now in the case that variable is returning data, and not an error code, you can use exceptions. But how is that possible? If you data ...
2
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1answer
340 views

Why would one transform a checked exception to an unchecked exception? [duplicate]

My buddy told me today that some programmers transform a checked exception (e.g. EJBException, SQLException...) to an unchecked (RuntimeException?) My buddy explained a call stack where if you change ...
1
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2answers
279 views

Java exception redundancy

To what extent should one make exceptions redundant or atomic to a method. For instance, suppose I have a method public void authenticate(String username, String password) that calls private void ...
38
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7answers
3k views

Are there legitimate reasons for returning exception objects instead of throwing them?

This question is intended to apply to any OO programming language that supports exception handling; I am using C# for illustrative purposes only. Exceptions are usually intended to be raised when an ...
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3answers
219 views

Throwing an exception for errors that can be fixed

Say I have a class like this: public class MyObject { public List<string> MyCollection { get; set; } } And a method like this: public void DoSomething(MyObject object) { ...
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3answers
208 views

When is a catch clause empty [duplicate]

I saw lots of questions and explanations regarding empty catch clauses but I was never actually sure what "empty" means. Is a catch clause like this empty? It clearly isn't empty for the eye because ...
2
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3answers
128 views

Avoiding null in a controller

I'm trying to work through how to write this code. def get(params): """ Fetch a user's details, or 404 """ user = User.fetch_by_id(params['id']) if not user: abort(404) # ...
6
votes
6answers
1k views

If the model is validating the data, shouldn't it throw exceptions on bad input?

Reading this SO question it seems that throwing exceptions for validating user input is frowned upon. But who should validate this data? In my applications, all validations are done in the business ...
2
votes
4answers
195 views

How do you hide error handling? [duplicate]

Many people consider exceptions to be a problem because they create invisible paths through your code. For example in this snippet: function writeToFile(text, filename): filehandle = open(filename) ...
1
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1answer
284 views

Does this violate the using exceptions for flow control “rule”?

I plan to make use of this interface in a plug-in architecture. /// <summary> /// Generic interface allowing you to react to an event. /// You can block the event or just use it for ...
-1
votes
6answers
2k views

Converting an empty string to a number [closed]

If you are designing a function which should conver a string to an integer, how would you convert an empty string? The question is only about this one particular input value (empty string). Between ...
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8answers
1k views

Best Practice for Argument Checking

Say I have a web service with a method MyWebServiceMethod(string passedValue). The web service calls a method MyServiceMethod(string passedValue) where the value from the web service is passed along. ...
28
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5answers
10k views

Why is there no 'finally' construct in C++?

Exception handling in C++ is limited to try/throw/catch. Unlike Object Pascal, Java, C# and Python, even in C++ 11, the finally construct has not been implemented. I have seen an awful lot of C++ ...
1
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2answers
757 views

Assertions vs Exceptions - is my understanding of the differences between the two correct? [duplicate]

Design By Contract uses preconditions and postconditions of the public methods in a class together to form a contract between the class and its clients. a) In code we implement preconditions ...
21
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3answers
907 views

Why is Option/Maybe considered a good idea and checked exceptions are not?

Some programming languages like e.g. Scala have the concept of Option types (also called Maybe), which can either contain a value or not. From what I've read about them they are considered widely to ...
1
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2answers
341 views

Wrapping specific checked exception in domain unchecked ones? [duplicate]

Uncle Bob says in Clean Code book that Unchecked Exceptions should be used. Now JDK has some checked exceptions: IOException, IllegalAccessException etc. which cannot be avoided. In my application ...
2
votes
7answers
768 views

better way to define an exception thrown by a method in Java?

I know how to define exceptions and all, but I'm not sure if the way I'm doing it is the most intuitive and readable by another users. I have a very simple method I've written that I want to throw an ...
15
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3answers
2k views

How many are too many nested function calls?

Quoted from MSDN about StackOverflowException: The exception that is thrown when the execution stack overflows because it contains too many nested method calls. Too many is pretty vague here. ...
17
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7answers
5k views

Are exceptions as control flow considered a serious antipattern? If so, Why?

Back in the late 90's I worked quite a bit with a code base that used exceptions as flow control. It implemented a finite state machine to drive telephony applications. Lately I am reminded of those ...
8
votes
3answers
7k views

Throwing an exception inside finally

Static code analyzers like Fortify "complain" when an exception might be thrown inside a finally block, saying that Using a throw statement inside a finally block breaks the logical progression ...
6
votes
2answers
334 views

The suffix Exception on exceptions in java

Specifying a suffix of Exception on exception classes feels like a code smell to me (Redundant information - the rest of the name implies an error state and it inherits from Exception). However, it ...
0
votes
2answers
190 views

Is there anything special to consider when writing my own exception class in C++? [closed]

If I wanted to implement my own version of the std::exception for no good reason, are there any special things about implementing this kind of object that I should be aware of? It seems like a fairly ...
-1
votes
1answer
161 views

Good library for combining .net stack traces [closed]

I currently report my production exceptions to a mysql database, where they have been collecting dust for the most part. The problem I faced is grouping the stack traces. I would like to be able to ...
0
votes
2answers
345 views

Why does File.Open in .Net throw exceptions and not follow exception handling best practices? [duplicate]

I have read at many places including this - http://msdn.microsoft.com/en-us/library/seyhszts.aspx - that you should use exception handling when something is truly exceptional. The .Net File.Open ...
3
votes
2answers
814 views

How to remove duplicate exception block code

I have good number of Service and DAO classes which has the same set of 30 line exception code block which gets repeated and it shows up in Code Duplication report. The approach which i can think of ...
9
votes
5answers
8k views

throwing runtime exception in Java application

I am working as a contractor designing enterprise Java application for my client in the role of a technical lead. The application will be used by end users and there will be a support team who will ...
54
votes
11answers
5k views

I've been told that Exceptions should only be used in exceptional cases. How do I know if my case is exceptional?

My specific case here is that the user can pass in a string into the application, the application parses it and assigns it to structured objects. Sometimes the user may type in something invalid. ...
33
votes
8answers
3k views

Are exceptions an OOP concept?

Having read a post yesterday, I realized I did not know much about the origin of exceptions. Is it an OOP related concept only? I tend to think it is, but again there are database exceptions.