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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33
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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 ...
-3
votes
0answers
39 views

die() or try/catch when interacting with MySql database in PHP? [closed]

A lot of tutorials and books I have been over and read have used the die() method to catch an exception when interacting with a local MySQL database For example: mysql_connect($dbhost, $dbuser, ...
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) ...
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 ...
3
votes
2answers
75 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
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 ...
3
votes
3answers
130 views

Returning a Flag Indicating Success

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 ...
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. ...
1
vote
2answers
531 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
64 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
85 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
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 ...
1
vote
1answer
203 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 { ...
33
votes
14answers
19k 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 ...
7
votes
3answers
1k views

Is there an issue with closing our database connections in the “Finally” block of a Try statement?

I'm doing some refactoring for our application, and trying to reduce the number of issues reported in our ISO Scan (a static code analysis tool based on HP Fortify). Right now, what I'm trying to ...
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 ...
5
votes
7answers
2k views

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

Why have many programmers moved to using exception handling for input or output? For these programmers, what is the motivation behind this decision?
0
votes
1answer
86 views

Code Inside Catch Block

This question is related to both of these questions - Efficient try / catch block usage? and Dealing with error in data - Idempotent approach. When I encounter a void while reading a GIS data file I ...
3
votes
1answer
65 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 = ...
7
votes
5answers
171 views

Do you have any team guidelines regarding exceptions? [closed]

My team recently inherited a project from a team where the amount of developers dropped so low they had to offload some work. One of the projects we inherited was a project littered with nested code, ...
3
votes
2answers
232 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 ...
23
votes
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 ...
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 ...
6
votes
8answers
4k 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
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
1answer
116 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
81 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
77 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
648 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
125 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
473 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
175 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
319 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
264 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 ...
8
votes
6answers
636 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
400 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
55 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) ...
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 ...
3
votes
2answers
234 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 ...
1
vote
2answers
153 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) { } ...
77
votes
8answers
12k 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
160 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
190 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
500 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
146 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 = ...
1
vote
3answers
135 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 ...
51
votes
8answers
11k 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 ...