Using normal class file in the servlet

Hello Friends;
Now my problem is ;
I generated a java file ;
import drasys.or.mp.*;
import drasys.or.mp.lp.*;
public class optimize
    public static void main(String[] args)
    try
        int r=1;
        int s=0;
.This file works perfect. It calls an API and there is no problem. But when I take this code into my servlet, then problem starts. First it says;
"java.lang.NoClassDefFoundError: drasys/or/mp/ScaleException"
but I know it is there. And I mounted the jar file.
Do you think there is a problem with my codes, because it works when it is outside of the servlet.
My servlet code is as follows;
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.sql.*;
import java.util.*;
import java.net.*;
import drasys.or.mp.*;
import drasys.or.mp.lp.*;
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        response.setContentType("text/html");
        PrintWriter out = response.getWriter();
         try
        int r=1;
        int s=0;
        int n = 3;
        int t,w,u,v,f;
        f = 1;
        int z=0;
        int y = 1;
        int l = 1;
        double [][][][] C = new double [1][1][n-1][n];
        double [][][][] D = new double [1][1][n-1][n];
        C[0][0][0][1]=2.5-0.92*r;
        C[0][0][0][2]=1.43-0.37*r;
        C[0][0][1][2]=1.14-0.48*r;
        D[0][0][0][1]=0.65*r+0.94;
        D[0][0][0][2]=0.31*r+0.75;
        D[0][0][1][2]=0.27*r+0.40;
     SizableProblemI prob = new Problem(n*(n-1)+1,n);
        prob.getMetadata().put("lp.isMaximize", "true");
        prob.newVariable("Lambda").setObjectiveCoefficient(1.0);
        for (t=0;t<=(n-1);t++)
            prob.newVariable("W"+t).setObjectiveCoefficient(0);
        final byte LTE = Constraint.LESS;
        final byte EQU = Constraint.EQUAL;
        for (v = 1;v <= n*(n-1);v++)
               prob.newConstraint("constr"+v).setType(LTE).setRightHandSide(y);
            prob.newConstraint("constr"+(n*(n-1)+1)).setType(EQU).setRightHandSide(1);
            // here, we are creating coefficients for lambda.
        for (u = 1; u <= n*(n-1); u++)
                prob.setCoefficientAt("constr"+u,"Lambda",y);
// here, we are creating coefficients for W�s.
        for(t = 0 ; t <= (n-2); t++)
            for (w = 1; w <= (n-1); w++)
                 if (t<w)
                     prob.setCoefficientAt("constr"+l, "W"+t, 1);
                     prob.setCoefficientAt("constr"+l,"W"+w, (-C[s][z][t][w]));
                     l = l + 1;
                     prob.setCoefficientAt("constr"+l, "W"+t, -1.0);
                     prob.setCoefficientAt("constr"+l, "W"+w, D[s][z][t][w]);
                     l = l + 1;
/* here , we are creating coefficients for the last formula which is w1+w2+w3+....Wn = 1 */
            for (f=0; f <= (n-1); f++)
            prob.setCoefficientAt("constr"+(n*(n-1)+1), "W"+f, 1);
/* API finds the solution below.*/
     LinearProgrammingI lp = new DenseSimplex(prob);
        double ans = lp.solve();
        System.out.println("Solution"+r+"="+ans);
        System.out.println(lp.getSolution());
        catch (drasys.or.mp.DuplicateException first)
         first.getMessage();
        catch (drasys.or.mp.NotFoundException second)
        catch (drasys.or.mp.InvalidException third)
        catch (drasys.or.mp.NoSolutionException fourth)
        catch (drasys.or.mp.UnboundedException fifth)
        catch (drasys.or.mp.InfeasibleException sixth)
        catch (drasys.or.mp.ConvergenceException seventh)
        catch (drasys.or.mp.ScaleException eigth)
           eigth.toString();

Thanks a lot for the reply.
Forgive me, I have no object oriented background,
even programming. I am just in the learning phase.This is a pretty advanced problem to tackle for your first programming task.
That's why it doesn't follow OO concepts. This part
will be connected to user input part, that I've
completed .Hmmm.
Successful programming depends on one idea: "divide and conquer". You take a big problem and solve it by dividing it into smaller chunks that you CAN handle. You get the solution you want by bringing the smaller chunks together.
In your case I'd recommend that you get the optimization code into a single object that you can test off-line, without Tomcat. It looks like you started to do that with your optimize class, but the mistake you made is to put so much code into the main() method. You can only call that on the command line. Better to encapsulate the rest of it into small methods that will let you instantiate an instance of optimize and call its methods. Once you have that working you can wrap it in a servlet if you want to use it in a Web app.
Separate how your optimizer gets its data from how it processes it. On a desktop app, it might be convenient to read input from a file on disk. A Web app might be better served by an XML stream.
Why I said "I know it is there" because it doesn't
give any other error message than that one, if it
couldn't see the jar file, wouldn't it give me lots
of error messages? Don't assume anything. It only needs one error, which is the one you get when it can't find a class. How many more do you need? The class loader couldn't find that class, so it printed the message and stopped.
"I mounted" the jar file means I'm using Netbeans, I
mounted it to that environment as suggested by
Netbeans, If you don't know Java or programming well, I'm guessing that you also don't know NetBeans. I'd recommend that you figure out how to make all this work without NetBeans before you add another complication to your life.
If you don't use NetBeans, all you have to do is add the JAR to your CLASSPATH using the -classpath option on javac.exe when you compile and java.exe when you execute.
Tomcat assumes that all the JAR files in your Web app's WEB-INF/lib are in the CLASSPATH. If you put it in there, Tomcat will find it.
you're right, I'm using Tomcat 5.0,
everything is working fine, user input servlets,
mysql connection etc. Only this part is causing the
problem now.If you've already got a Web app deployed and connected to MySQL, you're not doing too badly. Kudos to you - that's not too bad for someone who claims to be a programming novice.
I'll put that jar file into lib folder as you suggested thanks.I think that might be all you'll need. Try it and see.
Actually I saw an example it was using "throws
exception" , I couldn't figure out where to put it,
and I decided to get rid of the compiling errors just
putting bunch of catch statements.If you're saying that your code is throwing a lot of checked exceptions, and you added these extra catch blocks to get rid of them, another way to do it would be to simply have a single catch block, like this:
try
// your code in here
catch (Exception e)
e.printStackTrace();
}Polymorphism says that this catch block will handle all checked exceptions.
>
Looks like I don't know anything but I'm trying to
handle a big thing :))).Indeed you are. Anyone who can write a Web app and connect it to a relational database on their first try is hardly helpless. We're all ignorant, just about different things. Keep digging - you'll make this work.
But thank you soooo much for your detailed answer, and happy new year.
Shamil.And the same to you, Shamil. Good luck, and let me know how you make out.
%

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