Re: preoblem in jdbc postgresql and tomcat

hi,

some corrections.

CLASSPATH

my preference of jars in CLASSPATH is
tools.jar:pg74.215.jdbc3.jar:others:.

see the code change in Class.forName and url.

try{

Class.forName("org.postgresql.Driver");
Connection con =
DriverManager.getConnection("jdbc:postgresql://localhost:5432/dbname","postgres","postgres");
Statement stmt = con.createStatement();
ResultSet rs = stmt.executeQuery("select col1 from
test");

while(rs.next()){
out.println(rs.getString(1)+"<br>");

}
}catch(Exception e){
out.println(e);

}

if the above code works then you try same in jsp.

--Simon Moses.
Bangalore,
India.

--- java unix <javaunix123(at)yahoo(dot)co(dot)in> wrote:

> hi,
> i have installed postgresql-7.4.1,and
> tomcat4.1.31and
> j2sdk1.4.2_07
> for tomcat i have included path
> /usr/local/jakarta-tomcat-4.1.31
> for j2sdk path set is /usr/local/j2sdk1.4.2_07
> and CLASSPATH SET IS:
>
/usr/local/pgsql/pg73jdbc3.jar:/usr/local/pgsql/pg74.215.jdbc3.jar:/usr/local/pg
>
sql/postgresql-8.0-310.jdbc3.jar:/usr/local/j2sdk1.4.2_07/lib/tools.jar:/usr/loc
>
al/j2sdk1.4.2_07/jre/lib/rt.jar:/usr/local/jakarta-tomcat-4.1.31/common/lib/serv
>
let.jar:/usr/local/jakarta-tomcat-4.1.31/common/lib:/usr/local/pgsql:/usr/local/
> j2sdk1.4.2_07/jre/lib:/usr/local/j2sdk1.4.2_07/lib
> i have included all the paths
>
> all the above path are set in /etc/profile/
> and i set path for all three jar
>
files:/usr/local/pgsql/pg73jdbc3.jar:/usr/local/pgsql/pg74.215.jdbc3.jar:/usr/local/pg
> sql/postgresql-8.0-310.jdbc3.jar
>
> when i run this simple java program i get
> error as follows:
> [root(at)roopesh bin]# javac
> PostgreSQLTest.java//compile
> PostgreSQLTest.java: In class `PostgreSQLTest':
> PostgreSQLTest.java: In method
> `PostgreSQLTest.main(java.lang.String[])':
> PostgreSQLTest.java:7: Exception
> `java.lang.ClassNotFoundException' must be caught,
> or
> it must be declared in the `throws' clause of
> `main'.
>
> Class.forName("postgresql.Driver").newInstance();
> ^
> PostgreSQLTest.java:7: Exception
> `java.lang.InstantiationException' must be caught,
> or
> it must be declared in the `throws' clause of
> `main'.
>
> Class.forName("postgresql.Driver").newInstance();
> ^
> PostgreSQLTest.java:7: Exception
> `java.lang.IllegalAccessException' must be caught,
> or
> it must be declared in the `throws' clause of
> `main'.
>
> Class.forName("postgresql.Driver").newInstance();
>
> my PostgreSQLTest.java is as below
> import java.sql.*;
>
>
>
>
>
> class PostgreSQLTest {
> public static void main (String[] args) {
> try {
> Driver driver = (Driver)
>
> Class.forName("postgresql.Driver").newInstance();
> DriverManager.registerDriver(driver);
>
>
>
>
>
> String url = "jdbc:postgresql:javatest";
> Connection con =
> DriverManager.getConnection(url, "postgres", "");
> Statement stm = con.createStatement();
>
>
>
>
>
> stm.setQueryTimeout(10);
> ResultSet rs = stm.executeQuery("select col1
> from test");
>
>
>
>
>
> rs.next();
>
>
>
>
>
> System.out.println(rs.getString(1));
>
>
>
>
>
> } catch (SQLException e) {
>
>
>
>
>
> System.out.println("Exception!");
> System.out.println(e.toString());
> }
> }
> }
> This is one simple example
>
> Now when i tried to perform operations with tomcat
> simple sevlet works but with database operations i
> get
> the following errors
> file is:ShowBedrock.java
> import javax.servlet.*;
> import javax.servlet.http.*;
>
>
>
>
>
> public class ShowBedrock extends HttpServlet
> {
> public String getServletInfo()
> {
> return "Servlet connects to PostgreSQL
> database
> and displays result of a SELECT";
> }
>
>
>
>
>
> private Connection dbcon; // Connection for
> scope
> of ShowBedrock
>
>
>
>
>
> // "init" sets up a database connection
> public void init(ServletConfig config) throws
> ServletException
> {
> String loginUser = "postgres";
> String loginPasswd = "roopesh";
> String loginUrl =
> "jdbc:postgresql://localhost/bedrock";
>
>
>
>
>
> // Load the PostgreSQL driver
> try
> {
>
> Class.forName("org.postgresql.Driver");
> dbcon =
> DriverManager.getConnection(loginUrl, loginUser,
> loginPasswd);
> }
> catch (ClassNotFoundException ex)
> {
>
> System.err.println("ClassNotFoundException: " +
> ex.getMessage());
> throw new ServletException("Class not
> found Error");
> }
> catch (SQLException ex)
> {
> System.err.println("SQLException: " +
> ex.getMessage());
> }
> }
>
>
>
> //
> Use http GET
>
>
>
>
>
> public void doGet(HttpServletRequest request,
> HttpServletResponse response)
> throws IOException, ServletException
> {
> response.setContentType("text/html"); //
> Response mime type
>
>
>
>
>
=== message truncated ===

**************************
Visit My Home Page
http://www.geocities.com/ks_moses
updated: 28 Sep 2004.
Simon Moses
**************************

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