程序员需要知道一个方法可能抛出的所有异常，以便正确地使用它。因此，仅仅用一些异常来打击他并不一定能帮助一个粗心的程序员避免错误。

微小的好处被繁重的成本所抵消(特别是在较大、不太灵活的代码库中，不断修改接口签名是不切实际的)。

Static analysis can be nice, but truly reliable static analysis often inflexibly demands strict work from the programmer. There is a cost-benefit calculation, and the bar needs to be set high for a check that leads to a compile time error. It would be more helpful if the IDE took on the role of communicating which exceptions a method may throw (including which are unavoidable). Although perhaps it would not be as reliable without forced exception declarations, most exceptions would still be declared in documentation, and the reliability of an IDE warning is not so crucial.

这篇文章是我读过的关于Java异常处理的最好的文章。

它更倾向于未检查的异常，而不是已检查的异常，但这个选择的解释非常透彻，并基于强有力的论据。

我不想在这里引用太多的文章内容(最好是整体阅读)，但它涵盖了这个线程中未检查异常倡导者的大部分论点。尤其是这个论点(似乎很受欢迎):

以异常在API层底部某处抛出的情况为例，因为没有人知道这个错误甚至可能发生，即使它是一种非常合理的错误类型，当调用代码抛出它时(例如FileNotFoundException而不是VogonsTrashingEarthExcept…)在这种情况下，我们是否处理它并不重要，因为没有任何东西可以处理它)。

作者“回应”:

It is absolutely incorrect to assume that all runtime exceptions should not be caught and allowed to propagate to the very "top" of the application. (...) For every exceptional condition that is required to be handled distinctly - by the system/business requirements - programmers must decide where to catch it and what to do once the condition is caught. This must be done strictly according to the actual needs of the application, not based on a compiler alert. All other errors must be allowed to freely propagate to the topmost handler where they would be logged and a graceful (perhaps, termination) action will be taken.

主要的思想或文章是:

当涉及到软件中的错误处理时，唯一安全且正确的假设是，存在的每个子程序或模块都可能发生故障!

因此，如果“没有人知道这个错误甚至可能发生”，那么这个项目就有问题了。像作者建议的那样，这种异常至少应该由最通用的异常处理程序来处理(例如，处理所有没有更特定的处理程序处理的异常)。

很遗憾，似乎没有多少人发现这篇伟大的文章:-(。我衷心建议每一个犹豫哪种方法更好的人花点时间阅读它。

好吧，这不是关于显示堆栈跟踪或无声崩溃。它是关于在层与层之间沟通错误的能力。

The problem with checked exceptions is they encourage people to swallow important details (namely, the exception class). If you choose not to swallow that detail, then you have to keep adding throws declarations across your whole app. This means 1) that a new exception type will affect lots of function signatures, and 2) you can miss a specific instance of the exception you actually -want- to catch (say you open a secondary file for a function that writes data to a file. The secondary file is optional, so you can ignore its errors, but because the signature throws IOException, it's easy to overlook this).

实际上，我现在在一个应用程序中处理这种情况。我们将异常重新打包为AppSpecificException。这使得签名非常干净，我们不必担心在签名中爆炸。

当然，现在我们需要在更高的级别上专门化错误处理，实现重试逻辑等等。所有的东西都是AppSpecificException，所以我们不能说“如果一个IOException被抛出，重试”或“如果ClassNotFound被抛出，完全中止”。我们没有可靠的方法来获得真正的异常，因为当它们在我们的代码和第三方代码之间传递时，东西会一次又一次地重新打包。

这就是为什么我非常喜欢python中的异常处理。你只能捕获你想要和/或能处理的东西。其他所有东西都冒出来了，就好像你自己重新扔了它一样(不管怎样你已经这么做了)。

我一次又一次地发现，在我提到的整个项目中，异常处理分为3类:

Catch and handle a specific exception. This is to implement retry logic, for example. Catch and rethrow other exceptions. All that happens here is usually logging, and its usually a trite message like "Unable to open $filename". These are errors you can't do anything about; only a higher levels knows enough to handle it. Catch everything and display an error message. This is usually at the very root of a dispatcher, and all it does it make sure it can communicate the error to the caller via a non-Exception mechanism (popup dialogue, marshaling an RPC Error object, etc).

我最初同意你的观点，因为我一直支持受控异常，并开始思考为什么我不喜欢在. net中没有受控异常。但后来我意识到我并不喜欢受控异常。

回答您的问题，是的，我喜欢我的程序显示堆栈跟踪，最好是非常难看的跟踪。我希望应用程序爆发成一堆您希望看到的最糟糕的错误消息。

原因是，如果出现这种情况，我必须修复它，而且必须马上修复。我想马上知道有什么问题。

您实际处理了多少次异常?我说的不是捕获异常——我说的是处理异常?这样写太简单了:

try {
  thirdPartyMethod();
} catch(TPException e) {
  // this should never happen
}

我知道你可能会说这是一种糟糕的实践，“答案”是做一些异常(让我猜猜，记录它?)，但在现实世界(tm)中，大多数程序员就是不这样做。

所以，是的，我不想捕捉异常，如果我没有必要这样做，我希望我的程序在我搞砸的时候爆炸。默默的失败是最糟糕的结果。

In my opinion the checked exceptions are a very fine concept. Unfortunately the most programmers who have worked together we me have another opinion so that the projects have a lot of wrong used exception handling. I have seen that the most programmers create one (only one) exception class, a subclass of RuntimeException. That contains a message, sometimes a multi language key. I have no chance to argument against this. I have the impression that I talk to a wall when I explain them what anti patterns are, what a contracts of a methods are... I'm a little bit disappointed.

但是今天，对所有事情都有一个通用运行时异常的概念显然是一种反模式。他们使用它来检查用户输入。该异常被抛出，以便用户对话框可以从中产生错误消息。但并不是每个方法的调用者都是对话!通过抛出运行时异常，方法的契约被更改但没有声明，因为它不是一个受控异常。

希望他们今天学到了一些东西，并将在另一个地方进行检查(这是有用和必要的)。只使用受控异常不能解决问题，但受控异常会向程序员发出信号，表明他实现了错误的东西。

Ok... Checked exceptions are not ideal and have some caveat but they do serve a purpose. When creating an API there are specific cases of failures that are contractual of this API. When in the context of a strongly statically typed language such as Java if one does not use checked exceptions then one must rely on ad-hoc documentation and convention to convey the possibility of error. Doing so removes all benefit that the compiler can bring in handling error and you are left completely to the good will of programmers.

因此，一个人删除了Checked异常，比如在c#中所做的，那么如何以编程和结构的方式传达错误的可能性呢?如何通知客户端代码，这样那样的错误可能发生，必须处理?

在处理受控异常时，我听到了各种可怕的事情，它们被滥用了，这是肯定的，但未受控异常也是如此。我说，等几年，当api被堆叠在很多层的时候，你会乞求某种结构化的方法来传达失败。

以异常在API层底部某处抛出的情况为例，因为没有人知道这个错误甚至可能发生，即使它是一种非常合理的错误类型，当调用代码抛出它时(例如FileNotFoundException而不是VogonsTrashingEarthExcept…)在这种情况下，我们是否处理它并不重要，因为没有任何东西可以处理它)。

Many have argued that not being able to load the file was almost always the end of the world for the process and it must die a horrible and painful death. So yeah.. sure ... ok.. you build an API for something and it loads file at some point... I as the user of said API can only respond... "Who the hell are you to decide when my program should crash !" Sure Given the choice where exceptions are gobbled up and leave no trace or the EletroFlabbingChunkFluxManifoldChuggingException with a stack trace deeper than the Marianna trench I would take the latter without a cinch of hesitation, but does this mean that it is the desirable way to deal with exception ? Can we not be somewhere in the middle, where the exception would be recast and wrapped each time it traversed into a new level of abstraction so that it actually means something ?

最后，我看到的大多数争论都是“我不想处理异常，许多人不想处理异常。受控异常迫使我去处理它们，因此我讨厌受控异常。”完全消除这种机制并将其降级到地狱的深渊是愚蠢的，缺乏判断力和远见。

如果我们消除了受控异常，我们也可以消除函数的返回类型，并且总是返回一个“anytype”变量……这样生活就简单多了，不是吗?