Re: NullPointer at ResultSet.java:113

Hans,

I have fixed this problem in current sources.  next() no longer throws a
null pointer exception in this case.  It throws a more specific
SQLException indicating that the ResultSet is closed.

thanks,
--Barry

Hans Deragon wrote:
> Found the problem.  I do:
>
>   public static void main(String argv[]) throws Exception
>   {
>     Class.forName("org.postgresql.Driver");
>     Connection m_connection =
>       DriverManager.getConnection(DATABASEURL, USERNAME, PASSWORD);
>
>     ResultSet rs =null;
>     {
>       Statement st = m_connection.createStatement();
>       rs = st.executeQuery("SELECT * FROM stocksymbol");
>       st.close(); // <------ Problem!
>     }
>
>     System.err.println("\nHANS1" + rs);
>     rs.beforeFirst();
>     System.err.println("\nHANS1b");
>     while(rs.next())
>     {
>       System.err.println("\nHANS2\n");
>     }
>
> As you can see, the statement is closed before the ResultSet is used. It
> used to work with old Postgresql drivers, but not the most recent.  I
>  will simply remove the st.close() statement in my close.  I assume that
> there is a finalize() function in the Statement such that the close is
> done automatically when the instance is disposed.
>
> Still, it would be nice if we got a nice exception instead of a
> NullPointer exception.  Can someone correct the code to generate such
> exception?
>
> Sorry for the delay for my response. Its a pet project I am working on,
> on spare time.
>
>
> Sincerely,
> Hans Deragon
>
> Dave Cramer wrote:
>
>> Hans,
>>
>> Generally this means that there is nothing in the result set. Can you
>> give me some code which demonstrates this bug?
>>
>> Dave
>>
>> -----Original Message-----
>> From: pgsql-jdbc-owner@postgresql.org
>> [mailto:pgsql-jdbc-owner@postgresql.org] On Behalf Of Hans Deragon
>> Sent: Saturday, March 09, 2002 6:13 AM
>> To: pgsql-jdbc
>> Subject: [JDBC] NullPointer at ResultSet.java:113
>>
>>
>> Greetings.
>>
>>
>>    Upgraded yesterday to the latest pgjdbc2.jar.  I am using JDK
>> 1.4.0.   My database is postgresql-7.1.3-2.  I get:
>>
>>          at org.postgresql.jdbc2.ResultSet.next(ResultSet.java:113)
>>          at marketmanager.database.StockSymbol.list(StockSymbol.java:93)
>>          at
>> marketmanager.datacollection.stocks.YahooCollector.fetchDataFromWeb(Yaho
>> oCollector.java:56)
>>          at
>> marketmanager.datacollection.stocks.YahooCollector.fetchData(YahooCollec
>> tor.java:111)
>>          at
>> marketmanager.datacollection.FetchData.main(FetchData.java:13)
>>
>>    This is a bug for sure.  If there is something wrong I am doing, then
>>
>> it should have been caught by an exception and report to me what I was
>> doing wrong.  My code works with an older version of the postgresql jdbc
>>
>> driver.  And my code is pretty basic.
>>
>>    I could not find on the development website the source of this
>> code.   Anybody can provide a pointer?  May I suggest a direct
>> hyperlink to the code to the development site from the
>> http://jdbc.postgresql.org/?
>>
>>
>> Ciao
>> Hans
>>
>>
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>
>
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