Exception handling is the process of responding to the occurrence of anomalous or exceptional conditions requiring special processing – often changing the normal flow of program execution.

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5
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7answers
2k views

Why have many programmers moved to using exception handling for input or output? [on hold]

Why have many programmers moved to using exception handling for input or output? For these programmers, what is the motivation behind this decision?
22
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11answers
5k views

Is the 'finally' portion of a 'try … catch … finally' construct even necessary?

Some languages (such as C++ and early versions of PHP) don't support the finally part of a try ... catch ... finally construct. Is finally ever necessary? Because the code in it always runs, why ...
3
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1answer
40 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 = ...
0
votes
1answer
71 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 ...
30
votes
12answers
15k 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 ...
1
vote
2answers
374 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 ...
6
votes
8answers
3k views

Is it a acceptable approach to put try catch wherever null pointer exception occurs?

There are instances where the references to objects, fields, variables etc can be null and there might be a possible occurrence of Null Pointer exception occurring at that point. Is is a permanent ...
1
vote
1answer
111 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
1answer
41 views

proper exception handling (throwing/message) dll libary

I just wrote a dll library using vb.net. while testing, i got an error which i did not initially use a try-catch block. The code is Try 'The first four bytes are for the Command ...
0
votes
2answers
59 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 ...
0
votes
2answers
45 views

Catch unusual exceptions on production code for web apps

Lets say I have a web app, and despite my best testing efforts, several of the many thousands of people who uses it will find some way to generate an exception. Sure, I have error handling code for my ...
8
votes
2answers
609 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
1answer
97 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
225 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 ...
1
vote
1answer
133 views

How to make sure that the destructor cannot throw an exception?

I know that we can specify the compiler that a function is not throwing an exception by using noexcept specifier but noxecept functions can still throw exceptions . So, how to prevent destructor from ...
4
votes
2answers
208 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 ...
3
votes
5answers
185 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 ...
20
votes
5answers
4k 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 ...
8
votes
6answers
528 views

What are good ways of balancing informative exceptions and clean code?

With our public SDK, we tend to want to give very informative messages about why an exception occurs. For example: if (interfaceInstance == null) { string errMsg = string.Format( ...
0
votes
3answers
194 views

Convention for logging within nested try catch blocks

I've looked at this question but it doesn't really help solve my dilemma. System 1 calls system 2 within a try catch, the method in system 2 has it's own try catch, which sadly handles an exception ...
0
votes
1answer
45 views

Exception handling scope when dealing with nested exceptions

Assume you have one object that has two methods which both throw different exceptions. These methods must be used together. For instance: SqlCon{ static SqlCon connect(string user, string pass) ...
32
votes
10answers
12k 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 ...
54
votes
7answers
39k 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 ...
3
votes
2answers
158 views

Scala and exception handling [closed]

I am curious why exception handling is a topic often ignored in Scala. Is it the goal of the language (or the style) to not rely on exception handling except for external input/code? I was hoping ...
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vote
2answers
122 views

Is it a Good Practice to Catch All Exception? [duplicate]

The snippet below (in java) gives an example of my question. try { // code implementation here } } catch (Exception ex) { } ...
72
votes
8answers
10k views

Exceptions: Why throw early? Why catch late?

There are many well-known best practices about exception handling in isolation. I know the "do's and don'ts" well enough, but things get complicated when it comes to best practices or patterns in ...
2
votes
1answer
119 views

How to differentiate between exceptions coming from system and business logic?

I would like to differentiate between exceptions coming from business logic like requested database record does not exist attempt to store invalid business data (validation failed) provided CSV file ...
3
votes
2answers
182 views

How to deal with historic exception specifications in maintained C++ code

Today, I discovered a few exception specifications in legacy code I've to maintain, when Cppcheck 1.68 ([Inconclusive] but correctly) pointed out that the specified exceptions are not handled in ...
3
votes
4answers
494 views

Is it possible/good idea to reduce chance of crashing by catching Error?

I have a class the implements A which will run a certain method of class B. There is a requirement that this A should never crash when running this operation (which is not possible, right?). To ...
22
votes
5answers
3k views

How to deal with checked exceptions that cannot ever be thrown

Example: foobar = new InputStreamReader(p.getInputStream(), "ISO-8859-1"); Since the encoding is hardcoded and correct, the constructor will never throw the UnsupportedEncodingException declared in ...
0
votes
1answer
121 views

Where would be better to handle an exception?

Imagine I have the following DAO method: public Employee getEmployeeById(Integer id){ NamedParameterJdbcTemplate jdbcTemplate = new NamedParameterJdbcTemplate(getJdbcTemplate()); String sql = ...
22
votes
4answers
4k 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
votes
3answers
108 views

Coerce bad input or always crash early

The general consensus seems to favor the Crash Early approach, the most reputable source being the acclaimed Pragmatic Programmer book. And while I understand and agree with the advice in many ...
46
votes
8answers
10k views

Defensive Programming vs Exception Handling?

I'm working through the book "Head First Python" (it's my language to learn this year) and I got to a section where they argue about two code techniques: Defensive coding vs Exception handling. Here ...
0
votes
1answer
103 views

Replacing Throwing Exceptions with Notification in Validations

Martin Fowler recommends replacing exceptions with notifications when dealing with validations. Essentially, instead of throwing an exception, you append error messages to a Notification object that ...
16
votes
10answers
1k views

Why not use the word bug instead of exception? [closed]

If we refer to exceptions as bugs, why not just call it a bug in the first place instead of an exception? If in the code it's called exception and as soon as it occurs it's called a bug. Then why not ...
2
votes
1answer
72 views

Under which circumstances does it make sense to lose track of where an exception was thrown from?

Is there any valid reason why a catch block on a lower layer would throw back an exception caused by a higher, unknown layer using the following syntax: throw ex; ... rather than: throw; ... ? ...
0
votes
1answer
66 views

Advice needed on rethrowing an exception

Consider the following c# code: public class ExceptionManager { public static void TreatException(Exception ex) { if (ShowAndContinue(ex)) // display a user-friendly ...
3
votes
1answer
123 views

Exceptions in ANSI C

Would it be possible to implement exception mechanism in pure ANSI C similar to the one used in popular OOP languages (with familiar try-catch-finally clauses)? If yes then how? I'm especially ...
1
vote
4answers
217 views

Java exception handling design

I am trying to design a simple exception handling strategy for web services middleware using some ideas from here: http://northconcepts.com/blog/2013/01/18/6-tips-to-improve-your-exception-handling/. ...
31
votes
11answers
13k 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?
4
votes
3answers
1k views

Should service layer catch all dao exceptions and wrap them as service exceptions?

I have three layer Spring web app: dao, service and controllers. A controller never calls directly the dao, it does it through the service layer. Right now, most of the time if there is dao exception ...
1
vote
1answer
559 views

Exceptions: What to handle, what to throw

I have a custom configuration reader which performs various functions on top of .NET's CloudConfigurationManager and ConfigurationManager implementations, such as caching, type conversion, etc. The ...
1
vote
3answers
76 views

Logging instance information in Exceptions

During development on a large existing codebase I've started to capture variable values in my Exception logging. For example: public int Foo(int a, int b) { int returnInt; try{ returnInt ...
10
votes
4answers
640 views

Purposely raising exceptions to use catch

For a typical if...else wrapped with exception handling, is something like the following example a recommended practice to avoid code duplication? try { if (GetDataFromServer()) { ...
1
vote
3answers
229 views

Null checking whilst navigating object hierarchies

I had to implement some code which traversed a small object hierarchy to fetch a value and display it in a TextView object (this is Android / Java). I had to do this 6 times to populate 6 TextViews ...
2
votes
1answer
127 views

RefactorException: Good idea or bad idea?

When I'm doing large scale refactors I'm often commenting out the contents of methods and using NotImplementedExceptions for stuff that I still need to refactor. Problem is that this is interfering ...
0
votes
2answers
170 views

Logging Exception in multi-tier application

I'm building a multi-tier enterprise application using Spring. I have different layers: Controller, Business and Provider. Within the application I've built a custom error handling mini-framework that ...
1
vote
1answer
304 views

Why is Throwable initCause designed to be called only once?

I find it really odd that the initCause method of Java's Throwable class can only be called once, or even not at all (if the constructor accepting a Throwable was used). This makes exception chaining ...
2
votes
2answers
55 views

How to ensure the success of processes after a deadlock exception occurs?

No matter the programming language is and whatever the database is, the concept should be the same: I have 2 threads, each locking some database entities and inserting new data in database. Let's ...