Re: NullPointerExceptions in empty ResultSets

i figured out what the problem was.

in my code, i was doing this:

  resultSet.close()
  [snip a whole bunch of code]
  resultSet.last()
  resultSet.getRow();

in the previous version of the jdbc drivers, it quietly handled last() on a
closed result set and returned 0 from getRow() on a closed result set. now,
i get a null pointer exception when i call anything on a closed result set.

i suggest this is no bug and that it actually helped me improve my code.

sorry for the false alarm.

Regards,

Floyd Shackelford
4 Peaks Technology Group, Inc. <http://www.4peakstech.com/>
VOICE: 334.735.9428
FAX:   916.404.7125
EMAIL: FloydS@4PeaksTech.com <mailto:FloydS@4PeaksTech.com>
ICQ #: 161371538

acta non verba



-----Original Message-----
From: pgsql-jdbc-owner@postgresql.org
[mailto:pgsql-jdbc-owner@postgresql.org]On Behalf Of Dave Cramer
Sent: Thursday, June 13, 2002 1:17 PM
To: floyds@4peakstech.com
Cc: pgsql-jdbc@postgresql.org
Subject: Re: [JDBC] NullPointerExceptions in empty ResultSets


Try downloading the dev jar

I just tried

  public void testEmptyResult()
  {
    try
    {
      Statement stmt = con.createStatement();
      ResultSet rs = stmt.executeQuery("SELECT * FROM testrs where
id=100");
      rs.beforeFirst();
      rs.afterLast();
      assertTrue(!rs.first());
      assertTrue(!rs.last());
      assertTrue(!rs.next());


    }
    catch ( Exception ex )
    {
      fail( ex.getMessage() );
    }

and it passed with no problem

DAve
On Thu, 2002-06-13 at 14:00, Floyd Shackelford wrote:
>
> i just upgraded to the latest jdbc driver and am now getting errors in
empty
> ResultSets (i.e. the sql select returned 0 rows) where i used to not get
an
> error. here are some examples:
>
> java.lang.NullPointerException at
> org.postgresql.jdbc2.ResultSet.beforeFirst(ResultSet.java:876)
>
> java.lang.NullPointerException at
> org.postgresql.jdbc2.ResultSet.last(ResultSet.java:1133)
>
> please let me know if this is an error and if so:
>
> 1. how do i work around it for now
> 2. when can i have a new version of the jdbc jar file?
>
> Regards,
>
> Floyd Shackelford
> 4 Peaks Technology Group, Inc.
> VOICE: 334.735.9428
> FAX:   916.404.7125
> EMAIL: FloydS@4PeaksTech.com
> ICQ #: 161371538
> acta non verba
>
>
>
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