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PO
 

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  1. PO
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    <p>Look closely :) This</p> <pre><code>if (!db.isOpen() || db != null) { db.close(); db = null; } </code></pre> <p>will try to close the db only if it is <strong>not open</strong>. Also, I think there's something wrong with the</p> <pre><code>|| x != null </code></pre> <p>part of both clauses.</p> <p>In Java, the "double" logical operators are <em>conditional</em>. For || that means if the first argument is <strong>true</strong> then the second argument will not be evaluated at all, since logical OR will already be true no matter what. If it's not - then your link is checked for null. So, what you're doing is, you check whether cursor is closed. And if it <strong>is</strong> closed, you check the link for null - which obviously will be true given you succeeded calling any method on it, so no use of the second check.</p> <p>I think the right clauses will be</p> <pre><code>if ( poisCursor != null &amp;&amp; !poisCursor.isClosed()) // prevent NPE when calling .isClosed() in case poisCursor is null </code></pre> <p>and</p> <pre><code>if (db != null &amp;&amp; db.isOpen()) // same thing + note the absence of negation </code></pre> <p>(You can read more on conditional operators in detail here: <a href="http://docs.oracle.com/javase/tutorial/java/nutsandbolts/op2.html" rel="nofollow">http://docs.oracle.com/javase/tutorial/java/nutsandbolts/op2.html</a>)</p> <p><strong>Edit:</strong> @firebolt7 is right, you're losing reference to the object you get when calling open() in if clause.</p>
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    1. PODatabase not closed
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    1. PTAnswer
    1. USIvan Bartsov
    1. USIvan Bartsov
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    1. This table or related slice is empty.
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    1. COAlthough the `!db.isOpen()` looks wrong as you say, the second part of the check, `db != null`, will succeed, so this is not the cause of the error.
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      1. USGraham Borland
    2. COHmm, yes, you're right. So the attempt to close db should take place anyway. Then firebolt7 must be right - you're losing link to one of db instances, I've missed that part :)
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      1. USIvan Bartsov
    3. COThanks for looking into it, but error was as firebolt7 suggested. This if clause opened the db, I had it from before, to test if db exists and I never thought of closing it since I thought android will do it by itself as I have not plased this connection into a variable. My mistake. Also the negation of db.isOpen, you are right.
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      1. USDusko
 

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