JFreeChart - Database Interface

This chapter explains how you can read simple data from a database table and then use JFreeChart to create a chart of your choice.

Business Data

Consider we have following MySQL table mobile_tbl(mobile_brand VARCHAR(100) NOT NULL, unit_sale INT NO NULL);
Consider this table is having following records :

Mobile Brands	Unit Sales
IPhone5S	20
Samsung Grand	20
MotoG	40
Nokia Lumia	10

Chart Generation Using Database

Following is the code to create a Pie Chart based on the information provided in mobile_tbl table available in test_db in a MySQL database. Based on your requirements, you can use any other database.

import java.io.*; 
import java.sql.*; 
import org.jfree.chart.ChartUtilities;
import org.jfree.chart.ChartFactory; 
import org.jfree.chart.JFreeChart; 
import org.jfree.data.general.DefaultPieDataset;

public class PieChart_DB
{
   public static void main( String[ ] args )throws Exception
   {
      String mobilebrands[] = {
      "IPhone 5s",   
      "SamSung Grand",   
      "MotoG",            
      "Nokia Lumia" 
      };
      
      /* Create MySQL Database Connection */
      Class.forName( "com.mysql.jdbc.Driver" );
      Connection connect = DriverManager.getConnection( 
      "jdbc:mysql://localhost:3306/jf_testdb" ,     
      "root",     
      "root123");
      
      Statement statement = connect.createStatement( );
      ResultSet resultSet = statement.executeQuery("select * from dataset_tb" );
      DefaultPieDataset dataset = new DefaultPieDataset( );
      while( resultSet.next( ) ) 
      {
         dataset.setValue( 
         resultSet.getString( "brandname" ) ,
         Double.parseDouble( resultSet.getString( "datavalue" )));
      }
      JFreeChart chart = ChartFactory.createPieChart(
         "Mobile Sales",  // chart title           
         dataset,         // data           
         true,            // include legend          
         true,           
         false );

      int width = 560; /* Width of the image */
      int height = 370; /* Height of the image */ 
      File pieChart = new File( "Pie_Chart.jpeg" );
      ChartUtilities.saveChartAsJPEG( pieChart , chart , width , height );
   }
}

Let us keep the above Java code in PieChart_DB.java file, and then compile and run it from command prompt as follows:

$javac PieChart_DB.java 
$java PieChart_DB 

If everything is fine , it will compile and run to create JPEG image file named Pie_Chart.jpeg having the following chart.