java web application mysql connection error -

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i new in java. java environment 1. windows 8. 2. mysql - 5.5.27. 3. eclipse ide java ee devoper v-2. 5. apache tomcat v-7. 6. mysql-connector-java-5.1.28 bin rar 7. jdk 1.7. want connect mysql jsp file. add mysql-connector library resource. can not connect. code , error given in following. code: home.jsp

<%@ page language="java" contenttype="text/html; charset=iso-8859-1" pageencoding="iso-8859-1"%> <%@ page language="java" import="java.sql.connection"%> <%@ page language="java" import="java.sql.preparedstatement"%> <%@ page language="java" import="java.sql.resultset"%> <%@ page language="java" import="java.sql.sqlexception"%> <%@ page language="java" import="java.sql.drivermanager"%> <%@ page language="java" import="java.util.*"%> <!doctype html public "-//w3c//dtd html 4.01 transitional//en"  "http://www.w3.org/tr/html4/loose.dtd"> <html> <head> <meta http-equiv="content-type" content="text/html; charset=iso-8859-1"> <title>bengal contact list | home </title> </head> <body> <%  connection con = null; try { //class.forname("com.mysql.jdbc.driver"); string driver="com.mysql.jdbc.driver"; string url = "jdbc:mysql://localhost/java_contact"; string user = "root"; string password = ""; class.forname(driver); con = drivermanager.getconnection(url, user, password); } catch(classnotfoundexception cnfe){ system.out.println(cnfe); } catch(sqlexception ex){ system.out.println(ex); }  // connection con; // con=dbconnect.getdbconnect(); string sql="select * contactsinfo"; preparedstatement ps = con.preparestatement(sql); resultset rs = ps.executequery(sql);  %> <table border="1"> <tr> <td>id</td> <td>name</td> <td>designation</td> </tr> <%   while(rs.next()){ %> <td><%=rs.getint("id")%></td> <td><%=rs.getstring("name")%></td> <td><%=rs.getstring("designation")%></td> <% } %> </table>  <h1>now in home page.i want show table information of contact list.</h1> </body> </html>

error:

type exception report  message   description server encountered internal error () prevented   fulfilling request.  exception   org.apache.jasper.jasperexception: java.lang.nullpointerexception org.apache.jasper.servlet.jspservletwrapper.handlejspexception(jspservletwrapper.java:534) org.apache.jasper.servlet.jspservletwrapper.service(jspservletwrapper.java:457) org.apache.jasper.servlet.jspservlet.servicejspfile(jspservlet.java:391) org.apache.jasper.servlet.jspservlet.service(jspservlet.java:334) javax.servlet.http.httpservlet.service(httpservlet.java:722)   root cause   java.lang.nullpointerexception org.apache.jsp.home_jsp._jspservice(home_jsp.java:96) org.apache.jasper.runtime.httpjspbase.service(httpjspbase.java:70) javax.servlet.http.httpservlet.service(httpservlet.java:722) org.apache.jasper.servlet.jspservletwrapper.service(jspservletwrapper.java:419) org.apache.jasper.servlet.jspservlet.servicejspfile(jspservlet.java:391) org.apache.jasper.servlet.jspservlet.service(jspservlet.java:334) javax.servlet.http.httpservlet.service(httpservlet.java:722)   note full stack trace of root cause available in apache tomcat/7.0.12 logs.

please find out problem.

try give null checks rs.getint("id"), rs.getstring("name"), rs.getstring("designation"). nullpointerexception throwing there in page.

use same con object too.


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