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

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10
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5answers
581 views

What is the conceptual difference between finally and a destructor?

First, I am well aware of Why is there no 'finally' construct in C++? but a lengthy-growing comment discussion on another question seems to warrant a separate question. Apart from the issue ...
0
votes
1answer
46 views

Include exceptions in activity diagrams? [closed]

Should I include exceptions, like a TimeOutException or just general Exceptions, to a activity diagram? For example: A activity diagram describing a client-server connection. Several exceptions can ...
1
vote
2answers
104 views

Throwing exceptions in application configuration providers

Simple question: What is the best/common practice regarding to throwing errors for application configuration providers? Given is a simple key/value-based configuration source: class Configuration ...
2
votes
3answers
92 views

Is there particular circumstance that throwing root superclass exceptions is a good practice?

I've been taught that exceptions should be have concise meanings and should contain a message that explains to the client what the exceptional situation is. I am wondering, since I found a piece of ...
-3
votes
2answers
181 views

Why ever use exception throw (in C#) except for Class Library development? [duplicate]

Why would I ever throw exceptions in code? (except for one specific scenario where I am developing a class library which the consumers of it, will not want / be able to change). To be more specific, ...
48
votes
8answers
20k views

Return magic value, throw exception or return false on failure?

I sometimes end up having to write a method or property for a class library for which it is not exceptional to have no real answer, but a failure. Something cannot be determined, is not available, not ...
41
votes
12answers
26k views

Is it good practice to catch a checked exception and throw a RuntimeException?

I read some code of a colleague and found that he often catches various exceptions and then always throws a 'RuntimeException' instead. I always thought this is very bad practice. Am I wrong?
1
vote
2answers
3k views

Exception Handling in Java web application

I know exception handling is a topic often discussed in the world of Java. I've read a few threads on here and SO as well. ...
0
votes
1answer
151 views

Low cost exceptions implementation using metaprogramming [closed]

(preface - boring stuff, feel free to skip down to the implementation details) I need to provide exception handling to a language I am working on. It "compiles" to a subset of C, and since I don't ...
2
votes
2answers
87 views

How can a method handle validation and entity creation without output parameters?

I have 3 simple classes. A Reference, a Parent, and a Child. The Child knows the Reference and Parent instances it's associated with. Here they are, initialization and other data/methods omitted: ...
50
votes
4answers
27k views

Is it better to use assert or IllegalArgumentException for required method parameters?

In Java, which is more highly recommended, and why? Both types will throw exceptions, so in that regard handling them is the same. assert is slightly shorter, but I'm not sure how much that matters. ...
2
votes
0answers
71 views

Handling exceptions in multiple-issue CPUs

From what I read, VLIWs execute instructions in bundles, i.e. the CPU loads a bundle of instructions and dispatches them all at once. This is possible because the compiler scheduled instructions in ...
3
votes
5answers
560 views

Is it bad practice to throw multiple custom exceptions in Java? [duplicate]

I'm developing a Java web application. It is a three layered architecture: web > service > repository. I'm thinking of creating many exceptions - each specific to each individual error and in the ...
22
votes
2answers
1k views

Who should read Exception.Message if at all?

When designing exceptions should I write messages that a user or a developer should understand? Who should actually be the reader of exception messages? I find exception messages aren't useful at all ...
3
votes
2answers
525 views

Checked vs unchecked exception when validating documents in this service

I have a service that allow users to add dynamic content to a repository. So basically I have a generic Document class that contains a list of property for that specific object depending on what type ...
5
votes
3answers
86 views

Recommendations for adding exceptions messages to code [closed]

The "problem" that I am having right now its quite simple, I am creating a code with A LOT of validations, in case one of those fails it is supposed to throw an exception. In order to make the ...
1
vote
1answer
142 views

How often should I use try/catch statements? [duplicate]

Everything I've read says that they should be used when something that simply "shouldn't happen" does happen. But the thing is, there's a lot of things that could go wrong. For example, if I'm ...
2
votes
2answers
80 views

Advantages of extending the default Exception class

I've seen that it's possible to extend the default Exception class in PHP, enabling one to throw an IncorrectParameterTypeException exception, or a ValueOutOfRangeException exception (maybe these are ...
0
votes
1answer
124 views

Can I execute a query in a catch block of try-catch? [duplicate]

I want to confirm the right approach of using try-catch exception handler. I have written a query in a try block, and if any exception is thrown, it will execute a query in a catch block. Is this ...
33
votes
4answers
16k views

Why do iterators in Python raise an exception?

Here's the syntax for iterators in Java (somewhat similar syntax in C#): Iterator it = sequence.iterator(); while (it.hasNext()) { System.out.println(it.next()); } Which makes sense. Here's ...
4
votes
4answers
221 views

Should exceptions be raised higher up or lower down or both? [closed]

When calling some function in a Python application, the function often calls functions deeper down which again call functions deeper down, etc. It is easy to unknowlingly pass a bad value to the ...
12
votes
5answers
2k views

Do you throw an argumentexception or argumentnullexception from private methods?

I was just reviewing some code I wrote a while back, and can see that I have a couple of private methods that throw argumentnullexceptions and/or argumentexceptions if there are issues with the ...
3
votes
1answer
433 views

How to present domain model exceptions thrown through validation

In domain model of my web application I've an entity Foo which can be created only by a pojo FooBean: Foo.newInstance(FooBean fooBean) (Might have been better a Builder-pattern.) In the factory ...
5
votes
2answers
217 views

Exception clutter, how necessary is it? [duplicate]

Let's say I have a few methods that access the File System, and I want them to be a bit robust, I want to throw errors so the user can react: If the file doesn't have read / write rights, I want to ...
1
vote
7answers
353 views

Throwing an exception when a method does not complete or implement a work around? [duplicate]

I have been studying this subject quite a bit, and I am unsure of what's the best way. I still have a lot to go trough (books, blogs, stack exchange, etc), but I simply can't find a consensus. ...
1
vote
1answer
154 views

Proper propagation / handling of exceptions

I am trying to learn trough example on a proper way to handle exceptions. When should I catch it, when and how should I throw it further down the line ? In this example I have a very simple setup: ...
19
votes
7answers
5k views

Maybe monad vs exceptions

I wonder what are the advantages of Maybe monad over exceptions? It looks like Maybe is just explicit (and rather space-consuming) way of try..catch syntax. update Please note that I'm intentionally ...
11
votes
10answers
1k views

Should security restrictions cause a service to return null or throw an exception? [closed]

I'm in a bit of a disagreement with a more experienced developer on this issue, and wondering what others think about it; our environment is Java, EJB 3, services, etc. The code I wrote calls a ...
5
votes
2answers
369 views

Sending Exceptions as event arguments

Is it a good idea to send Exceptions as EventArgs in C#? (And not actually throw the Exception). I have a class that performs a long running asynchronous task. If something goes wrong in the middle ...
9
votes
5answers
10k views

Is it not a good practice to handle runtime exceptions in the code?

I am working on a Java application, and I see that Run time exceptions are handled in many places. For example, try { //do something }catch(NullPointerException e){ ...
41
votes
7answers
21k 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++ ...
36
votes
11answers
18k views

Is catching general exceptions really a bad thing?

I typically agree with most code analysis warnings, and I try to adhere to them. However, I'm having a harder time with this one: CA1031: Do not catch general exception types I understand the ...
31
votes
7answers
66k views

Why doesn't “object reference not set to an instance of an object” tell us which object?

We're launching a system, and we sometimes get the famous exception NullReferenceException with the message Object reference not set to an instance of an object. However, in a method where we have ...
9
votes
3answers
3k views

Decision for Unchecked Exceptions in Scala

As a java programmer, I have always been critical of Unchecked Exceptions. Mostly programmers use it as an en-route to coding easiness only to create trouble later. Also the programs (though untidy) ...
7
votes
3answers
397 views

Should I make my own exceptions, or co-opt similar exceptions for slightly non-standard purposes?

This is a general design question, but I'm focusing on C# and .NET because those are the languages I'm working with right now. Should I create my own, new exception classes, or co-opt existing ...
3
votes
3answers
116 views

Is this a valid situation for returning rather than throwing an exception?

This is not something I would ever normally do, but I have a situation where some existing legacy code is being reused in a new application. The code is shared and needs to be used by both the legacy ...
4
votes
2answers
178 views

Handling exceptions in a loop without breaking the loop (try to process all members)

Scenario: I have a loop that iterates over an Array of COM objects and does some work using them. My fear, working with COM objects, is that some exception will creep up (possibly on another ...
3
votes
4answers
196 views

Design strategy for wrapping exceptions

I'm implementing a type of Repository for a framework/library that has (roughly) the following: public interface FooRepository { boolean contains(String id); Foo fetch(String id); void ...
1
vote
2answers
77 views

Is it valid to expect/throw an exception using a custom caching system?

Imagine some code like the following: class Cache { private Map<String, String> values = new HashMap<String, String>(); public String getFromCache(String key) { if ...
4
votes
3answers
177 views

Returning a Flag Indicating Success [closed]

Whenever I'm writing code, I always stub out my methods like this (not necessarily using generics): public T MyMethod() { T result = default(T); // or null return result; } This always ...
4
votes
2answers
393 views

Rust-style error handling in C++

I've been reading some articles on how Rust does error handling using the Result<T, E> type and to me it seems like a hybrid best-of-both-worlds (exceptions and return codes) solution which can ...
2
votes
2answers
113 views

Try Catch and Flow Control dilemma

I am aware that doing Flow Control on a program using a try-catch block is bad practice, but I can't see how to do it in another way when the error caught needs a redirection of the code's execution. ...
1
vote
2answers
600 views

Using Statement lambda in exception handling

Following is a code snippet from MVP Win Forms application and this explanation would be helpful when answering the questions. My DAL doesn't handle exceptions and it will be propagated up to the ...
3
votes
1answer
86 views

Connection between futures and exceptions?

Is there a connection between futures and exceptions? async-await looks very similar to throw-catch.
1
vote
3answers
122 views

Where should PDOExceptions be dealt with?

I wrote a database wrapper class to help with queries and I'm trying to figure the best way to implement try-catch blocks. In my database class, I have a helper function; public function ...
2
votes
1answer
40 views

Storing exception information as a member variable for query later, bad practice? [duplicate]

I looking at the best way to handle exceptions, the answer to this question may be to handle the exception in a different place or to not handle to exception at all but to control the flow of the ...
2
votes
1answer
336 views

Should we encapsulate everything in a try{} block in a Try object?

Why can't I make a class for a Try including what I try and then run that in the try {} block? Why is it impractical? class DBConnectTry extends Try { TryResponse response[] attempt(TryObject ...
4
votes
2answers
171 views

Strategies to analyze collected exceptions

We want to add error feedback to our application. I had a look at existing solutions (e.g. raygun.io), but these work "in the cloud", which is a no-go for us: most installations of our application ...
1
vote
1answer
258 views

Why would we need to rollback twice before closing in a finally block?

I'm trying to implement the change in database connection closing suggested in this question's answers. More than once, I've come across this block of code at the end of my try blocks: try { ...
43
votes
14answers
28k views

Is using nested try-catch blocks an anti-pattern?

Is this an antipattern? It is an acceptable practice? try { //do something } catch (Exception e) { try { //do something in the same line, but being less ambitious ...