Here is a code that retrieves the data from the database and create a bar chart from the values.

import java.io.*;
import java.sql.*;
import org.jfree.data.*;
import org.jfree.data.category.*;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartUtilities;
import org.jfree.chart.plot.PlotOrientation;

public class Chart{
        public static void main(String[] args) throws Exception {
        Class.forName("com.mysql.jdbc.Driver").newInstance();
        Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "root" );
        Statement st=conn.createStatement();
        ResultSet rs=st.executeQuery("SELECT * from result");
                DefaultCategoryDataset dataset = new DefaultCategoryDataset();
                while(rs.next()){
                  dataset.setValue(rs.getInt("result"), "Marks", rs.getString("name"));
                }
                JFreeChart chart =ChartFactory.createBarChart3D("Test", "Name", "Marks",
                dataset, PlotOrientation.VERTICAL, true, true, false);
                try{
                ChartUtilities.saveChartAsJPEG(new File("C:/chart.jpg"),
                chart,400, 300);
               }
               catch (IOException e){
               System.out.println("Problem in creating chart.");
             }
        }
}