Populated javafx BarChart with database value

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.chart.BarChart;
import javafx.scene.chart.CategoryAxis;
import javafx.scene.chart.NumberAxis;
import javafx.scene.chart.XYChart;
import javafx.scene.chart.PieChart.Data;
import javafx.scene.layout.Pane;
import javafx.stage.Stage;

public class row extends Application{
NumberAxis xAxis = new NumberAxis();
     CategoryAxis yAxis = new CategoryAxis();
     static String itemA = "Attendance";
     static String itemB = "CT_Marks";
     static String itemC = "Assignment";
     static String itemD = "Others";
     Connection connection;
     Statement statement;
     int i=1;
     int j=2;
XYChart.Data<String, Number> data =  new XYChart.Data<String, Number>();
public void start(Stage stage){
initializeDB();
Pane pane=new Pane();
pane.setPrefSize(600, 500);
BarChart<String,Number> bchart=new BarChart<String,Number>(yAxis, xAxis);
bchart.setPrefSize(550, 450);
bchart.setTitle("Summary");
   xAxis.setLabel("Values");
   xAxis.setTickLabelRotation(45);
   yAxis.setTickLabelRotation(45);
   yAxis.setLabel("Menus");
   XYChart.Series series1 = new XYChart.Series();
   XYChart.Series series2 = new XYChart.Series();
   series1.setName("2016");
      try{
      String sql="select ID,marks from value";
      ResultSet rset=statement.executeQuery(sql);
      while(rset.next()){
      XYChart.Data<String, Number> data =  new XYChart.Data<String, Number>(rset.getString(i),rset.getDouble(j));
      series1.getData().add(data);
      data.nodeProperty().addListener(new ChangeListener<Node>(){
      public void changed(ObservableValue<? extends Node>ov,Node oldNode,final Node node){
      if(node!=null){
      if(data.getYValue().doubleValue()>15){
      node.setStyle("-fx-bar-fill:green");
      }else if(data.getYValue().doubleValue()>10){
      node.setStyle("-fx-bar-fill:navy");
      }else if(data.getYValue().doubleValue()>5){
      node.setStyle("-fx-bar-fill:red");
      }else if(data.getYValue().doubleValue()>0){
      node.setStyle("-fx-bar-fill:black");
      }
      }
      }
      });
     
     
      } i++;j++;
   
      }catch(Exception e){
     
      }
   bchart.getData().addAll(series1);
   pane.getChildren().add(bchart);
Scene scene=new Scene(pane);
//scene.getStylesheets().add(getClass().getResource("application.css").toExternalForm());
stage.setScene(scene);
stage.show();
}

private void initializeDB() {
try{
Class.forName("com.mysql.jdbc.Driver");
connection=DriverManager.getConnection("jdbc:mysql://localhost/mysql?useUnicode=yes&characterEncoding=UTF-8","root","");
statement=connection.createStatement();
}
catch(Exception ex){
ex.printStackTrace();
}
}

public static void main(String[] args) {
launch(args);

}

}