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copied!<p><strong>Do not catch a <code>NullPointerException</code></strong>.</p> <p>A <code>NullPointerException</code> is a sign that your code is not adhering to some contract. If it is possible that <code>game</code> can be <code>null</code>, then you need to make an explicit test:</p> <pre><code>if(game != null) { ... } else { ... } </code></pre> <p>If <code>game</code> should not be null, then you can ensure the correctness of your code by using <code>assert</code>.</p> <pre><code>assert game != null; ... </code></pre> <p>What is more worrying is that <code>game</code> seems to be a private member of your class. In this case <code>game</code> should probably not be <code>null</code> (although there are cases where this <em>can</em> happen). Are you initializing it properly in your constructor? I'd say that the first thing you should is to make sure that <code>game</code> is being initialized properly. Otherwise your code will end up being littered with un-necessary <code>null</code>-checks. For example, what if <code>gameWindow</code> in the <code>Game</code> class wasn't initialized properly? You would need to have another <code>null</code>-check for that:</p> <pre><code>if(game !== null && game.gameWindow != null) { ... } else { ... } </code></pre> <p>So you should first make sure that your object's private members are being initialized properly. If they are, and it turns out that there is a valid use-case for <code>game</code> being <code>null</code>, then you would need an explicit <code>null-</code>check. It's always better to test for <code>null</code> than catching a <code>NullPointerException</code>. Other than the fact that exceptions should not be used to control the flow of your business logic, what if a valid <code>NullPointerException</code> (due to a programming error) was generated somewhere up the chain? Now your <code>catch</code> will catch it and you won't know about it; this can lead to some really nasty and hard-to-find bugs.</p>

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