Generate Gaussian ("normally") distributed random data using random.nextGaussian()

The Random.nextGaussian() method returns the next pseudorandom, Gaussian ("normally") distributed double value with mean 0.0 and standard deviation 1.0 from this random number generator's sequence.

            int mean = 50;
            int standardDeviation = 10;
            data = mean + (int)(random.nextGaussian() * standardDeviation);

package javafx_histogram;

import java.util.Random;
import javafx.application.Application;
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.control.Label;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

/**
 * @web http://java-buddy.blogspot.com
 */
public class JavaFX_Histogram extends Application {
    
    int DATA_SIZE = 1000;
    int data[] = new int[DATA_SIZE];
    int group[] = new int[10];
    
    @Override
    public void start(Stage primaryStage) {
        
        prepareData();
        groupData();
        
        Label labelInfo = new Label();
        labelInfo.setText(
            "java.version: " + System.getProperty("java.version") + "\n" +
            "javafx.runtime.version: " + System.getProperty("javafx.runtime.version")
        );
        
        final CategoryAxis xAxis = new CategoryAxis();
        final NumberAxis yAxis = new NumberAxis();
        final BarChart<String,Number> barChart = 
            new BarChart<>(xAxis,yAxis);
        barChart.setCategoryGap(0);
        barChart.setBarGap(0);
        
        xAxis.setLabel("Range");       
        yAxis.setLabel("Population");
        
        XYChart.Series series1 = new XYChart.Series();
        series1.setName("Histogram");       
        series1.getData().add(new XYChart.Data("0-10", group[0]));
        series1.getData().add(new XYChart.Data("10-20", group[1]));
        series1.getData().add(new XYChart.Data("20-30", group[2]));
        series1.getData().add(new XYChart.Data("30-40", group[3]));
        series1.getData().add(new XYChart.Data("40-50", group[4])); 
        
        series1.getData().add(new XYChart.Data("50-60", group[5]));
        series1.getData().add(new XYChart.Data("60-70", group[6]));
        series1.getData().add(new XYChart.Data("70-80", group[7]));
        series1.getData().add(new XYChart.Data("80-90", group[8]));
        series1.getData().add(new XYChart.Data("90-100", group[9]));
        
        barChart.getData().addAll(series1);
        
        VBox vBox = new VBox();
        vBox.getChildren().addAll(labelInfo, barChart);
        
        StackPane root = new StackPane();
        root.getChildren().add(vBox);
        
        Scene scene = new Scene(root, 800, 450);
        
        primaryStage.setTitle("java-buddy.blogspot.com");
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
    
    //generate dummy random data
    private void prepareData(){

        Random random = new Random();
        for(int i=0; i<DATA_SIZE; i++){
            //data[i] = random.nextInt(100);
            
            int mean = 50;
            int standardDeviation = 10;
            data[i] = mean + (int)(random.nextGaussian() * standardDeviation);
            
        }
    }
    
    //count data population in groups
    private void groupData(){
        for(int i=0; i<10; i++){
            group[i]=0;
        }
        for(int i=0; i<DATA_SIZE; i++){
            if(data[i]<=10){
                group[0]++;
            }else if(data[i]<=20){
                group[1]++;
            }else if(data[i]<=30){
                group[2]++;
            }else if(data[i]<=40){
                group[3]++;
            }else if(data[i]<=50){
                group[4]++;
            }else if(data[i]<=60){
                group[5]++;
            }else if(data[i]<=70){
                group[6]++;
            }else if(data[i]<=80){
                group[7]++;
            }else if(data[i]<=90){
                group[8]++;
            }else if(data[i]<=100){
                group[9]++;
            }
        }
    }
    
}