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    <p>I am not trying to sound patronizing or anything. I will probably say a lot of stuff you already know. But bear with me, while I try to explain why solving your problem will not be possible using compiler warnings.</p> <p>Deriving two classes from each other, never mind if they are exception classes or not, means, they are in a <em>is-a</em> relation. For example:</p> <pre><code>public class Vehicle {} public class Car extends Vehicle {} public class Boat extends Vehicle {} </code></pre> <p>means: <code>Car</code> <em>is a</em> <code>Vehicle</code>. <code>Boat</code> <em>is a</em> <code>Vehicle</code>.</p> <p>With <code>throws</code>, or more to the point, <code>catch</code> (later on), you specify the type you want to throw/be caught. Now, assuming that <code>Vehicle</code> was derived from <code>Exception</code>, you could do this:</p> <pre><code>try { // ... } catch (Car c) { // You caught a car. Not any vehicle, a real, honking car. } </code></pre> <p>By doing this, however:</p> <pre><code>try { // ... } catch (Vehicle v) { // You caught some vehicle. Any vehicle. } </code></pre> <p>you specify that you do not care if you catch cars, boats, bicycles or whatever, as long as it is mobile and transports passengers or cargo. Because a car <em>is a</em> vehicle. And a boat <em>is a</em> vehicle.</p> <p>To sum up, <strong>what you are trying to do goes completely against the very idea of the object oriented approach.</strong> You cannot make the compiler report any "suppressed" or "hidden" exceptions, because they really are not. With <code>throws</code>, they are very much defined, and with <code>catch</code>, they are very much handled. So the compiler does not even understand your problem, let alone offer some way to prevent it.</p> <p>As the comments say, a static code analysis would pretty much be the only option to do what you want to do. Something which I have used for occasions like these, is <a href="http://checkstyle.sourceforge.net/" rel="nofollow">Checkstyle</a>. Since what you want is quite unusual, I do not think that Checkstyle has a predefined check for what you want. In fact, it DOES have a check for <a href="http://checkstyle.sourceforge.net/config_coding.html#RedundantThrows" rel="nofollow">the exact opposite</a>.</p> <p>So you will probably have to write your own check for it, but Checkstyle allows this rather easily. I would start by reading the source code of the <code>RedundantThrows</code> check, then doing the opposite of what it does. This should make your custom check to fail if you do not list ALL thrown checked exceptions in the method <code>throws</code> signature.</p>
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    1. POList all unreported exceptions (including exceptions which super classes of declared exceptions)
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    1. COYou are totally misunderstanding my question - I am not asking for a way to report uncaught `Car` when I am catching `Vehicle`. I am asking for a way to report uncaught `Car` when I am not catching any exception and the `throw spec` declares the exceptions in the order `throws Vehicle, Car`.
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    2. CONo, I am not, actually, but apparently you misunderstood my answer. I used `catch` instead of `throws` just because it is easier to understand. The problem, and answer, are exactly the same. `throws Vehicle, Car` is redundant, as far as the compiler is concerned, because a `Car` is a `Vehicle`. So `throws Vehicle` already encompasses `Car`, `Boat`and all possible derivations of `Vehicle`. The point of my answer was the sentence I have now written in bold.
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    3. COI want a way to find this information - it doesn't matter whether it comes from a compiler or any other tool.
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