Re: java.lang.NullPointerException on imbricated queries

Each Statement may only have 1 ResultSet open at a time. If you want to
access multiple Results at the same time, you need to use 2 different
Statements. See below

1 Query1 = "SELECT * FROM example1;";
2 rs1 = stmt1.executeQuery(Query1);
3 while (rs1.next()) {
4 Query2 = "SELECT * FROM example2;
5 rs2 = stmt2.executeQuery(Query2);
6 while (rs2.next()) {
7 // Something .../...
8 }
9 }

Garrick

On Mon, 2003-06-30 at 04:06, Kallol Nandi wrote:
> Are you using GNU's jdk or Sun's jdk?
>
> Regards,
> Kallol.
> -----Original Message-----
> From: pgsql-jdbc-owner(at)postgresql(dot)org
> [mailto:pgsql-jdbc-owner(at)postgresql(dot)org]On Behalf Of Olivier BULLAT
> Sent: Monday, June 30, 2003 2:29 PM
> To: pgsql-jdbc(at)postgresql(dot)org
> Subject: [JDBC] java.lang.NullPointerException on imbricated queries
>
>
> Hello,
>
> We have a web application in Apache, Posgresql 7.2, servlet java (JDK
> 1.2), Jserv and jdbc7.2dev-1.2.jar.
> A lot of programs runs normally with JDBC access to postgresql. But when
> we use two imbricated queries like this example, a message JAVALANGEXEPTION
> java.lang.NullPointerException occurs:
>
> 1 Query1 = "SELECT * FROM example1;";
> 2 rs1 = stmt.executeQuery(Query1);
> 3 while (rs1.next()) {
> 4 Query2 = "SELECT * FROM example2;
> 5 rs2 = stmt.executeQuery(Query2);
> 6 while (rs2.next()) {
> 7 // Something .../...
> 8 }
> 9 }
>
> Programme DetailsRapports.java: JAVALANGEXEPTION
> java.lang.NullPointerException:
> java.lang.NullPointerException:
> at org.postgresql.jdbc2.ResultSet.next(ResultSet.java:113)
> at DetailsRapports.AfficheEntrees(DetailsRapports.java:68)
> at DetailsRapports.service(DetailsRapports.java:43)
> at javax.servlet.http.HttpServlet.service(HttpServlet.java:588)
> at
> org.apache.jserv.JServConnection.processRequest(JServConnection.java:317)
> at org.apache.jserv.JServConnection.run(JServConnection.java:188)
> at java.lang.Thread.run(Thread.java:479)
>
> This message occurs on line 3 "while (rs1.next()) {" after a first good
> Query1 and a first good Query2.
>
> Any help would be appreciated.
>
>
>
> --------------------------------------------------------------------------
> Olivier BULLAT
> Responsable du Centre de Ressources Informatiques
> Institut Francais de Mecanique Avancee - IFMA
> Campus de CLERMONT-FERRAND / Les Cezeaux
> BP 265
> 63175 AUBIERE Cedex
> Tel: 04.73.28.80.35
> Fax: 04.73.28.81.00
> mail: Olivier(dot)Bullat(at)ifma(dot)fr
> http://www.ifma.fr
> --------------------------------------------------------------------------
>