Bug #5069 NullPointerExcept: ResultSetMetaData.getColumnCount(ResultSetMetaData.java:315)

• Submitted: 17 Aug 2004 3:38
• Modified: 31 Mar 2014 7:27
• Reporter: Ken Johanson
• Status: Not a Bug
• Category: Connector / J
• Severity: S2 (Serious)
• Version: 3.1-nightly-20040815
• OS: Any
• Assigned to: Mark Matthews
• CPU Architecture: Any

[17 Aug 2004 3:38] Ken Johanson

Description:
Getting a NullPointerException at com.mysql.jdbc.ResultSetMetaData.getColumnCount(ResultSetMetaData.java:315)

How to repeat:
The code that causes this is roughly:

PreparedStatement ps = con.prepareStatement(query);
//ps.setObject(i+1, args[i]);
ResultSet rs = ps.executeQuery();
ResultSetMetaData md = rs.getMetaData();
colLen = md.getColumnCount();

[17 Aug 2004 4:02] Mark Matthews

Unfortunately your rough code doesn't make this repeatable (just checked, I don't get a null pointer exception with that code).

My guess is you're calling getMetaData() _after_ the result set has been closed? (either explicitly, or implicitly by closing the statement that created it, or executing another query on the same statement?).

I will add a check so that you get the _correct_ exception, but you will now see a 'Result set closed' exception.

[17 Aug 2004 5:07] Ken Johanson

Right you are, it was being closed in a try-finally, on this bug and the last relating to PreparedStatement. My Aplogies, and thank you. Case closed.