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copied!<p>JLS hunting:</p> <blockquote> <p>It is a compile-time error if a final variable is assigned to unless it is definitely unassigned (§16) immediately prior to the assignment.</p> </blockquote> <p>Quoth chapter 16:</p> <blockquote> <p>V is definitely unassigned before a catch block iff all of the following conditions hold: </p> <p><strong>V is definitely unassigned after the try block.</strong><br> V is definitely unassigned before every return statement that belongs to the try block.<br> V is definitely unassigned after e in every statement of the form throw e that belongs to the try block.<br> V is definitely unassigned after every assert statement that occurs in the try block.<br> V is definitely unassigned before every break statement that belongs to the try block and whose break target contains (or is) the try statement.<br> V is definitely unassigned before every continue statement that belongs to the try block and whose continue target contains the try statement. </p> </blockquote> <p>Bold is mine. After the <code>try</code> block it is unclear whether <code>i</code> is assigned.</p> <p>Furthermore in the example</p> <pre><code>final int i; try { i = foo(); bar(); } catch(Exception e) { // e might come from bar i = 1; } </code></pre> <p>The bold text is the <em>only</em> condition preventing the actual erroneous assignment <code>i=1</code> from being illegal. So this is sufficient to prove that a finer condition of "definitely unassigned" is necessary to allow the code in your original post.</p> <p>If the spec were revised to replace this condition with</p> <blockquote> <p>V is definitely unassigned after the try block, if the catch block catches an unchecked exception.<br> V is definitely unassigned before the last statement capable of throwing an exception of a type caught by the catch block, if the catch block catches an unchecked exception.</p> </blockquote> <p>Then I believe your code would be legal. (To the best of my ad-hoc analysis.)</p> <p>I submitted a JSR for this, which I expect to be ignored but I was curious to see how these are handled. Technically fax number is a required field, I hope it won't do <em>too</em> much damage if I entered +1-000-000-000 there.</p>

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