Re: NullPointer at ResultSet.java:113 - Mailing list pgsql-jdbc

Hi Dave.


   I do not see a difference.  If I close a Statement, I still get later
a NullPointerException.

   I have a question, should I actually close a Statement at that point
or not?  I have no clue what I am supposed to do. For the moment, I
removed the st.close() statement in my code.  Performance and resource
management are not on my list of priorities.


Sincerely,
Hans Deragon

Dave Cramer wrote:

> Hans,
>
> I rebuilt the 7.2dev driver on the download site. Let me know if that
> fixes your problem
>
> Dave
>
>
>>-----Original Message-----
>>From: pgsql-jdbc-owner@postgresql.org
>>[mailto:pgsql-jdbc-owner@postgresql.org] On Behalf Of Hans Deragon
>>Sent: Thursday, March 14, 2002 6:42 PM
>>To: Dave@micro-automation.net
>>Cc: 'pgsql-jdbc'
>>Subject: Re: [JDBC] NullPointer at ResultSet.java:113
>>
>>
>>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.fetchDataFr
>>omWeb(Yaho
>>
>>>oCollector.java:56)
>>>         at
>>>
>>>
>>marketmanager.datacollection.stocks.YahooCollector.fetchData(Y
>>ahooCollec
>>
>>>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
>>>
>>>
>>>
>>>
>>---------------------------(end of
>>
>>>broadcast)---------------------------
>>>TIP 5: Have you checked our extensive FAQ?
>>>
>>>http://www.postgresql.org/users-lounge/docs/faq.html
>>>
>>>
>>>
>>>
>>>
>>
>>
>>---------------------------(end of
>>broadcast)---------------------------
>>TIP 6: Have you searched our list archives?
>>
>>
> http://archives.postgresql.org
>
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 3: if posting/reading through Usenet, please send an appropriate
> subscribe-nomail command to majordomo@postgresql.org so that your
> message can get through to the mailing list cleanly
>
>