An exception is an occurrence in an application process that requires deviation from the program's normal flow.
7
votes
5answers
8k 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){
...
36
votes
7answers
16k 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++ ...
33
votes
11answers
14k 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 ...
25
votes
7answers
51k 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
2k 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
1answer
164 views
Do we need to validate entire module usage or just arguments of public methods?
I've heard that it is recommended to validate arguments of public methods:
Should one check for null if he does not expect null?
Should a method validate its parameters?
MSDN - CA1062: Validate ...
7
votes
3answers
348 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
93 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 ...
0
votes
4answers
166 views
Handling DomainExceptions using REST endpoint
Suppose I'm doing some DDD.
Now, I have a microservice reflecting a bounded context/a part of a bounded context.
Now, suppose there is a REST endpoint:
'/somedomainmodel/someaction'
My API user is ...
3
votes
4answers
139 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
52 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
2answers
212 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
71 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.
...
3
votes
1answer
65 views
Connection between futures and exceptions?
Is there a connection between futures and exceptions? async-await looks very similar to throw-catch.
2
votes
1answer
31 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
289 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
89 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
3answers
103 views
Is an application supposed to recover from a exception thrown in PHP?
What if the programmer uses Exceptions for debugging? Would it be better in that case to just report the failure and immediately interrupt the script since ideally all bugs should be fixed radically?
...
14
votes
2answers
8k 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 ...
27
votes
5answers
6k 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 ...
3
votes
1answer
66 views
How to handle Django get-single-instance-in-view pattern?
A lot of my Django views start a little bit like this:
try:
# here request.POST could also be request.GET or a captured URL parameter
MyModel.objects.get(user = request.user, some_attr = ...
63
votes
5answers
5k views
How to write a good exception message
I'm currently doing a code review and one of the things I'm noticing are the number of exceptions where the exception message just seems to reiterate where the exception occurred. e.g.
throw new ...
3
votes
2answers
237 views
Best strategy to find the root cause when exception is swallowed by 3rd party
I am sure we have all run into a scenario where a 3rd part API complains with an incomplete stack trace. In essence the error handling in the 3rd party API does something like this,
catch ...
173
votes
9answers
12k views
Why do many exception messages not contain useful details?
It seems there is a certain amount of agreement that exception messages should contain useful details.
Why is it that many common exceptions from system components do not contain useful details?
A ...
2
votes
3answers
144 views
Extended usage of an exception
I'm in the process of building a routing system for learning purposes and have encountered an issue which I think is a bit in the grey area of best practices. Can you guys help me decide if this is ...
-1
votes
1answer
107 views
Should i avoid FaultException for Custom Validation Error messages to client [duplicate]
We are as a team working on a project which currently using WCF as in between client and server.
All business rules are written on managers classes which are used by service so its means no ...
0
votes
1answer
81 views
Pass by value result with exceptions [closed]
I have a doubt with the pass-by-value-result method. As far as I understood, it passess the value of the parameter to the function, and then get the result as the function ends. But what happens with ...
90
votes
22answers
17k views
Are null references really a bad thing?
I've heard it said that the inclusion of null references in programming languages is the "billion dollar mistake". But why? Sure, they can cause NullReferenceExceptions, but so what? Any element of ...
36
votes
4answers
3k views
Python Forgiveness vs. Permission and Duck Typing
In Python, I often hear that it is better to "beg forgiveness" (exception catching) instead of "ask permission" (type/condition checking). In regards to enforcing duck typing in Python, is this
try:
...
3
votes
3answers
386 views
No exceptions C++ and partially constructed objects
Looking over Joint Strike Fighter Air Vehicle C++ Coding Standard, rule AV 73 states something on the lines: Default c++ constructors should be avoided if that means leaving object in a partially ...
7
votes
5answers
451 views
Rethrow the same exception to provide more info
Is it a good practice to rethrow the same exception to provide more specific information? For example:
var sitemap = "a string containing an XML document";
try {
// throw InvalidXmlException if ...
4
votes
1answer
144 views
Should I always throw the most specific or should I try to generalize exception types?
Say you normally have FooException.
/**
* @throw FooException If Foo is invalid for searching.
*/
public bool exists(Foo a)
But at some point you need to have two more specific exceptions for ...
0
votes
4answers
71 views
What's the best way to handle slightly different exceptions?
My code right now looks something like this:
void throw_illegal_part_of_input_exception(char c) {}
void throw_invalid_input_length_exception(int position, int length) {}
void ...
1
vote
1answer
119 views
Using exceptions as regular objects [duplicate]
I have views that handle different errors in my application. For example error 404, 403 and such, giving my errors a more user-friendly presentation. By assumption, they get passed in an exception, so ...
0
votes
2answers
82 views
How do I find out what type of exception I am supposed to raise?
I suppose this question is valid for any programming language that can handle (or at least throw) an exception. However I will stick to Python as an example.
The top 2 answers to the following ...
8
votes
2answers
649 views
How should I handle logger failures?
In several of our company's applications, we use a custom logger. It's fairly robust, though we may replace it with something like NLog in the future. One of the logger's tasks is to log any ...
0
votes
2answers
651 views
Is it possible to prune the stacktrace returned for a custom exception in PHP
I am working on a project in PHP that does a lot of input validation and can throw different custom exception classes in various layers of the application. To make the project code easier to read, ...
4
votes
1answer
118 views
When should I subclass an exception in Python?
In my code there are about seven places where I raise an exception. All of these exceptions are treated the same: print an error to log file, return software state to default and exit.
During code ...
0
votes
1answer
127 views
Is there are any common pattern/practice to handle exception list (Java)? [closed]
Suppose I've got a sophisticated parser for something.
And a I don't want Throw Early/Fail-Fast strategy.
If I've got multiple problems, i want to have list of exceptions in my log file
because I want ...
4
votes
2answers
484 views
When to create a custom exception in C#
I'm writing a class to interface with a simple hardware device over a COM port. The device can configured to use various modes, so my class has a SetOperatingMode function, that takes in an enum of ...
0
votes
1answer
78 views
Return values and exceptions [closed]
I wrote simple function that returns a string depending on which condition is TRUE. Here is my code:
private String getMyString() {
if(!mStrigMember.isEmpty()) {
return mStrigMember;
...
4
votes
2answers
323 views
Exception versus return code in DAO pattern
After reading a lot about the abusive use of exceptions in Java and how you should let an exception bubble up through the different layers of an application, I've come to a point where I don't know ...
4
votes
2answers
276 views
Is checking that a property doesn't throw an exception a valid unit test?
I'm writing tests for the following class:
public class Foo : INotifyPropertyChanged
{
private int _failCount;
private int _totalCount;
public double FailRate
{
get
{
double ...
1
vote
2answers
216 views
Smells in exception handling: how to separate between public and internal exceptions?
During the development of a small web API, we decided to separate internal exceptions from public exceptions. Public exceptions are HTTP exceptions, that translate into HTTP responses with proper ...
30
votes
8answers
4k views
Is throwing an exception an anti-pattern here?
I just had a discussion over a design choice after a code review. I wonder what your opinions are.
There's this Preferences class, which is a bucket for key-value pairs. Null values are legal ...
3
votes
5answers
268 views
Exception handling and 3rd party library
I'm currently having an issue with a 3rd party control library provider. They have an exception occulting culture that gets in the way of my general fail-fast approach when developing software.
An ...
24
votes
5answers
6k views
Why design a modern language without an exception-handling mechanism?
Many modern languages provide rich exception handling features, but Apple's Swift programming language does not provide an exception handling mechanism.
Steeped in exceptions as I am, I'm having ...
57
votes
7answers
49k views
Why use try … finally without a catch clause?
The classical way to program is with try ... catch. When is it appropriate to use try without catch?
In Python the following appears legal and can make sense:
try:
#do work
finally:
#do ...
0
votes
1answer
170 views
How shall I handle event loop exceptions?
What is the best practice for handling exceptions thrown from event handlers/listeners in a event loop? For example:
class EventLoop
{
public:
void start(); //create a thread which calls run();
...
51
votes
9answers
6k views
Throw exception or let code fail
I am wondering if there are any pros and cons against this style:
private void LoadMaterial(string name)
{
if (_Materials.ContainsKey(name))
{
throw new ArgumentException("The ...
