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- I am trying to load or u can say register my sql jdbc driver with the use of ServletConfig interface 2 answers
I am able to load my my sql jdbc driver from the other ways but when am trying to register it with the use of servletconfig interface it gives an exception: java.lang.ClassNotFoundException: Though I know the concept of servletconfig interface and trying to do it by following the concept but am failed.
Here is my web.xml code
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>newuser</servlet-name>
<servlet-class>com.rr.org.newuser</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>newuser</servlet-name>
<url-pattern>/newuser</url-pattern>
</servlet-mapping>
<servlet>
<description></description>
<display-name>Validation</display-name>
<servlet-name>Validation</servlet-name>
<servlet-class>com.pi.org.Validation</servlet-class>
<init-param>
<param-name>driver</param-name>
<param-value>com.mysql.jdbc.Driver</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>Validation</servlet-name>
<url-pattern>/Validation</url-pattern>
</servlet-mapping>
<servlet>
<description></description>
<display-name>inbox</display-name>
<servlet-name>inbox</servlet-name>
<servlet-class>com.qq.org.inbox</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>inbox</servlet-name>
<url-pattern>/inbox</url-pattern>
</servlet-mapping>
</web-app>
here is my java file in my java class it gives an warning The value of the local variable driver is not used.
package com.pi.org;
import java.io.IOException;
import javax.sql.*;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class Validation
*/
public class Validation extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public Validation() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
Boolean valid= false;
PrintWriter out = response.getWriter();
String username= request.getParameter("user");
String password= request.getParameter("pass");
try{
ServletConfig config = getServletConfig();
String driver = config.getInitParameter("driver");
Class.forName("driver");
Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/newdata","root","annie1993");
PreparedStatement ps= conn.prepareStatement("select * from emp ");
ResultSet rs = ps.executeQuery();
while(rs.next()){
if(username.equals(rs.getString(1))&& password.equals(rs.getString(2)))
{
valid= true;
}
}
if(valid)
{
request.setAttribute("user", username);
RequestDispatcher rd = request.getRequestDispatcher("inbox");
rd.forward(request, response);
}
else{
RequestDispatcher rd = request.getRequestDispatcher("/index");
rd.include(request, response);
out.print("<html><body>either username or password is incorrect<body><html>");
}
}catch(Exception e){e.printStackTrace();}
}
}
and here is the exception which i got
java.lang.ClassNotFoundException: driver
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1305)
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1157)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:259)
at com.pi.org.Validation.doPost(Validation.java:58)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:644)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:610)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:516)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1086)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:659)
at org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:223)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1558)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1515)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
