Unable to call java class from servlet

[santbir singh]

Hello sir i am new to java and using Apache Tomcat 7.0.22

and i am trying to compile two classes (one is servlet and second is java class called by servlet). After completing my coding i tried to compile both classes first i comiled java classes which was successfully compiled and .class file created but when i tried to compile servlet file its gave me error at the line where i created and instantiate object for java class.

I also got this problem before that time but i solved it by seting the classpath in cmd by putting the command:-

set classpath = .; C:\Program Files (x86)\Apache Software Foundation\Apache Tomcat 7.0.22\webapps\loginnapp\WEB-INF\classes\;

in this folder i contained to java files (Function.java(servlet) and (Register.java(class)))

code for previous was working fine ...

but now second time i got this problem again and i again used this trick but fail to solve the problem. i set the classpath as i setted previously:-

set classpath = .; C:\Program Files (x86)\Apache Software Foundation\Apache Tomcat 7.0.22\webapps\LoginApp\WEB-INF\classes\;

in this folder i contained to java files (Controler.java(servlet) and (ConnectDB.java(class)))

but this time my classpath trick is not working some guys saying that we can set the classpath onetime only second class path not accepted and some says we have to set the both classpath old and new (in one time) because when we set one classpath and after that we set second it removes previous one. I can't understand what that mean

but i am searching for fix (all in one) solution that will work for all application... No seperate path for seprate application
why this problem creates an issue in window 7 please help me to find solution .... if anybody fix it permanently.....

here is code for my servlet:-

import java.io.*;
import java.lang.*;
import javax.servlet.*;
import javax.servlet.http.*;

public class Controler extends HttpServlet
{
public void doGet(HttpServletRequest req, HttpServletResponse res) throws IOException, ServletException
{
res.setContentType("text/html");
PrintWriter O=res.getWriter();

String user1,pass1,cpass1,npass1,button;

user1=req.getParameter("user");
pass1=req.getParameter("pass");
cpass1=req.getParameter("cpass");
npass1=req.getParameter("npass");
button=req.getParameter("Submit1");
O.println("program running");
try
{	
		if(button.equals("Register"))
		{
			if(pass1.equals(cpass1))
			{
				ConnectDB ca=ConnectDB();                //  I AM GETTING ERROR ON THIS LINE
				if(ca.add_user(user1,pass1)>0)
				{
				O.println("Registered Successfully");
				}
				else
				{
				O.println("Unsuccessfull Registration");
				}	
			}
			else
			{
			O.println("Password Field Doesn't Matched");
			}
		}
		else if(button.equals("Remove"))
		{
			if(pass1.equals(cpass1))
			{
			O.println("User Removed");
			}
			else
			{
			O.println("Password Field Doesn't Matched");
			}
		}
		else if(button.equals("Login"))
		{
		O.println("Login Completed");
		}	
		else if(button.equals("Change Password"))
		{
			if(cpass1.equals(npass1))
			{
			O.println("Password Changed Successfully");
			}
			else
			{
			O.println("Password Field Doesn't Matched");
			}
		}	
		else 
		{
		O.println("Button Label Doesn't Matched ");
		}
		
	
	

}
catch(NullPointerException npe) { }

}    //doGET method closing bracket

}    //Class closing bracket

[Milan Sutaria]

is the webapp name spelled correctly on second occassion? I see "loginnapp" on first classpath and then I see "LoginApp"

[santbir singh]

Hello I am sorry i am not understanding what you mean. I think my code was unable to understand and readable. But I am looking now to my code it seems fine. I think you correct it for me .
One other thing you was asking about the application name loginapp and LoginApp.

I want to clear that loginapp is my previous application which was solved by setting the classpath

and LoginApp is second application where i got stuck and the solution of setting classpath is not working.

If you understand please reply

loginapp and LoginApp is two different application not the name same application name

[vipul John]

Hello sir i am new to java and using Apache Tomcat 7.0.22

and i am trying to compile two classes (one is servlet and second is java class called by servlet). After completing my coding i tried to compile both classes first i comiled java classes which was successfully compiled and .class file created but when i tried to compile servlet file its gave me error at the line where i created and instantiate object for java class.

May be you have put your java classes in default package. This will be one of the reasons.

"It is a compile time error to import a type from the unnamed package". Check whether your classes are in packages.

Thanks
Vipul Kumar.

[vipul John]

ConnectDB ca=ConnectDB();

The above line does not instantiate class.

You should use

   ConnectDB ca=new ConnectDB();  

[R. Jain]

santbir singh wrote:

				ConnectDB ca=ConnectDB();                //  I AM GETTING ERROR ON THIS LINE			

Is object really getting created here??

[R. Jain]

vipul bondugula wrote:

   ConnectDB ca=new ConnectDB();  

Well, I didn't saw the last answer...