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    <p>The first version is <em>nearly</em> right - but there are two problems:</p> <ol> <li><p>Your method doesn't declare that it can throw <code>IOException</code>, but your use of <code>valueFile.seek</code> could throw an exception. Either you need to change the method declaration, or catch and handle the exception.</p></li> <li><p>The compiler doesn't know that <code>System.exit(0)</code> will never return normally - it thinks it's a normal method. So you have to change your catch block to end with something like:</p> <pre><code>return; </code></pre> <p>or</p> <pre><code>throw new AssertionError("We'll never get here."); </code></pre> <p>At that point, the compiler knows that if it gets beyond the try/catch block, <code>valueFile</code> <em>is</em> definitely assigned.</p></li> </ol> <p>Note that if you move <em>everything</em> inside the <code>catch</code> block, both problems will go away - but I'd suggest that you'd be better off <em>not</em> catching anything at all, and instead just declaring that the method may throw <code>IOException</code>:</p> <pre><code>public void foo(int iterations) throws IOException { RandomAccessFile valueFile = new RandomAccessFile("valuefile.txt", "rw"); for (int i = 0; i &lt; iterations; i++) { valueFile.writeDouble(randomizer.nextDouble()*200); } for (int i = 0; i&lt; iterations; i++) { double total = 0; valueFile.seek(0); // Presumably you'd read the contents here? } } </code></pre> <p>... except you should <em>also</em> close the file when you're done with it, using a try-with-resources statement if you're using Java 7, or just a try/finally block otherwise.</p>
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    1. POAccessing a file object outside a try/catch block that creates it (Java)
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    1. COWhat? I think you should re-read the question.
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    2. CO@DaoWen: I've reread it - and I was answering the *second* error reported, not the first. Will edit to include both.
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    3. COYour answer for the second error question is still way off. The error isn't saying that the variable is _unititialized_, but rather that the symbol _doesn't exist_. This is because he declares the variable inside the `try` block in the second example, which means it's no longer in scope for `valueFile.seek(0)`.
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