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PONullPointerException from Connection.preparedStatement for SQLite JDBC
 

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  1. PONullPointerException from Connection.preparedStatement for SQLite JDBC
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    <p>what I'm trying to do is get a ResultSet from a SQL statement from which then I can derive certain values. What I seem to be having troubles with is the preparing of the prepared statement which occurs at this line.</p> <pre><code>String sql = "SELECT " + dataState + " FROM " + table + whereState + ";"; java.sql.PreparedStatement prep = conn.prepareStatement(sql); // Error here </code></pre> <p>I've already checked that the variable conn is not null. All the values in the statement are not null and the stack trace shows this.</p> <blockquote> <p>java.lang.NullPointerException <br>at org.sqlite.PrepStmt.(PrepStmt.java:37) <br>at org.sqlite.Conn.prepareStatement(Conn.java:231) <br>at org.sqlite.Conn.prepareStatement(Conn.java:224) <br>at org.sqlite.Conn.prepareStatement(Conn.java:213) <br>at org.utilities.storagemethods.SQLiteMethod.load(SQLiteMethod.java:223) <br>at org.utilities.DataManager.load(DataManager.java:97) <br>at org.utilities.Test.main(Test.java:21)</p> </blockquote> <p>A print of the sql statement shows that it gives this.</p> <pre><code>SELECT testString, testBool, testObj FROM testTable WHERE testInt=?; </code></pre> <p>You can ascertain the values from the given string.</p> <p>What I can't figure out is what I'm doing wrong to cause this, if you're curious about what sqlite system I'm using, you can find the home page here: <a href="http://www.zentus.com/sqlitejdbc/" rel="nofollow">http://www.zentus.com/sqlitejdbc/</a></p> <p>Thanks in advance for any help on this. I'm completely stumped.</p> <p>Note: In an attempt to save resources, I was caching my Connection's, and re-using them later. When I try re-getting the connection, it works perfectly. Is there a way I can cache them or do I need to load them every time I want to use it?</p>
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    1. USMark
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    1. COCan't imagine what you want to ask and what your problem is. Your first SQL statement is completely wrong. You need to post some relevant code.
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    2. COWhy don't you use your SQL statement something like this `"SELECT dataState FROM table where State = ?"; prep.setString(1, "Some State");`?
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      1. PONullPointerException from Connection.preparedStatement for SQLite JDBC
      1. USLion
    3. COThe variable `conn` is not null, looking at the source code the NPE is happening because `conn.db();` returns null. Is your connection configured properly? Check the error log for exceptions during the connection creation.
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      1. USThe Scrum Meister
 

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