## Using FusionCharts with JSP > Creating Drill-down charts
In our previous example, we had used FusionCharts to plot a chart using data stored in database. We'll now extend that example itself to create a drill-down chart which can show more information. If you recall from previous example, we were showing the sum of factory output in a pie chart as under:
In this example, we'll extend this example, so that when a user clicks on a pie slice for a factory, he can drill down to see date wise production for that factory.
Setting up the pie chart for Link
To set up the pie chart to enable links for drill-down involves just minor tweaking of our previous BasicDBExample.jsp. We basically need to add the link attribute for each <set> element. We create a new page Default.jsp from the previous page in DBExample folder with the following code changes:
<%@ include file="../Includes/FusionCharts.jsp"%> <%@ include file="../Includes/DBConn.jsp"%> <%@ page import="java.sql.Statement"%> <%@ page import="java.sql.ResultSet"%> <%@ page import="java.sql.Date"%> <HTML> <HEAD> <TITLE>FusionCharts - Database and Drill-Down Example</TITLE> <SCRIPT LANGUAGE="Javascript" SRC="../../FusionCharts/FusionCharts.js"></SCRIPT> </HEAD> <BODY> <% /* In this example, we show how to connect FusionCharts to a database. For the sake of ease, we've used a database with just contains two tables, which are linked to each other. */ //Database Objects - Initialization Statement st1=null,st2=null; ResultSet rs1=null,rs2=null; String strQuery=""; //strXML will be used to store the entire XML document generated String strXML=""; //We also keep a flag to specify whether we've to animate the chart or not. //If the user is viewing the detailed chart and comes back to this page, he shouldn't //see the animation again. String animateChart=null; animateChart = request.getParameter("animate"); //Set default value of 1 if(null==animateChart||animateChart.equals("")){ animateChart = "1"; } //Generate the chart element strXML = "<chart caption='Factory Output report' subCaption='By Quantity' pieSliceDepth='30' showBorder='1' formatNumberScale='0' numberSuffix=' Units' animation='" + animateChart + "'>"; //Query to retrieve data strQuery = "select * from Factory_Master"; st1=oConn.createStatement(); rs1=st1.executeQuery(strQuery); String factoryId=null; String factoryName=null; String totalOutput=""; String strDataURL=""; while(rs1.next()) { factoryId=rs1.getString("FactoryId"); factoryName=rs1.getString("FactoryName"); strQuery = "select sum(Quantity) as TotOutput from Factory_Output where FactoryId=" + factoryId; st2=oConn.createStatement(); rs2 = st2.executeQuery(strQuery); if(rs2.next()){ totalOutput=rs2.getString("TotOutput"); } // Encoding the URL since it has a parameter strDataURL = encodeDataURL("Detailed.jsp?FactoryId="+factoryId,"false",response); //Generate <set label='..' value='..'/> strXML += "<set label='" + factoryName + "' value='" +totalOutput+ "' link='"+strDataURL+"' />"; //Close recordset rs2=null; st2=null; } //Finally, close <chart> element strXML += "</chart>"; //close resultset,statement,connection try { if(null!=rs1){ rs1.close(); rs1=null; } }catch(java.sql.SQLException e){ //do something System.out.println("Could not close the resultset"); } try { if(null!=st1) { st1.close(); st1=null; } }catch(java.sql.SQLException e){ //do something System.out.println("Could not close the statement"); } try { if(null!=oConn) { oConn.close(); oConn=null; } }catch(java.sql.SQLException e){ //do something System.out.println("Could not close the connection"); } //Create the chart - Pie 3D Chart with data from strXML String chartCode = createChart("../../FusionCharts/Pie3D.swf", "", strXML, "FactorySum", 600, 300, false, false); %> <%=chartCode%> </BODY> </HTML>
As you can see in the code above, we're doing the following: Include FusionCharts.js JavaScript class and FusionCharts.asp , to enable easy embedding of FusionCharts. We then include DBConn.jsp, which gives the connection to our Access database. Thereafter, we generate the XML data document by iterating through the resultset. We store the XML data in strXML variable. To each <set> element, we add the link attribute, which points to Detailed.jsp - the page that contains the chart to show details. We pass the factory id of the respective factory by appending it to the link. We finally URL Encode the link, which is a very important step. Finally, we create the chart using createChart() method and pass strXML as dataXML and render the chart. Let's now shift our attention to Detailed.jsp page.
Creating the detailed data chart page
The page Detailed.jsp contains the following code:
<%@ include file="../Includes/FusionCharts.jsp"%> <%@ include file="../Includes/DBConn.jsp"%> <%@ page import="java.sql.Statement"%> <%@ page import="java.sql.ResultSet"%> <%@ page import="java.text.SimpleDateFormat"%> <HTML> <HEAD> <TITLE>FusionCharts - Database and Drill-Down Example</TITLE> <SCRIPT LANGUAGE="Javascript" SRC="../../FusionCharts/FusionCharts.js"></SCRIPT> </HEAD> <BODY> <% /*This page is invoked from Default.jsp. When the user clicks on a pie slice in Default.jsp, the factory Id is passed to this page. We need to get that factory id, get the information from database and then show a detailed chart. */ //First, get the factory Id String factoryId=null; //Request the factory Id from parameters factoryId = request.getParameter("FactoryId"); String chartCode=""; if(null!=factoryId){ ResultSet rs=null; String strQuery; Statement st=null; java.sql.Date date=null; java.util.Date uDate=null; String uDateStr=""; String quantity=""; String strXML=""; //Generate the chart element string strXML = "<chart palette='2' caption='Factory " +factoryId +" Output ' subcaption='(In Units)' xAxisName='Date' showValues='1' labelStep='2' >"; //Now, we get the data for that factory strQuery = "select * from Factory_Output where FactoryId=" +factoryId; st=oConn.createStatement(); rs = st.executeQuery(strQuery); while(rs.next()){ date=rs.getDate("DatePro"); quantity=rs.getString("Quantity"); if(date!=null) { uDate=new java.util.Date(date.getTime()); // Format the date so that the displayed date is easy to read SimpleDateFormat sdf=new SimpleDateFormat("dd/MM"); uDateStr=sdf.format(uDate); } strXML += "<set label='" +uDateStr+"' value='" +quantity+"'/>"; } //Close <chart> element strXML +="</chart>"; //close resultset,statement,connection try { if(null!=rs){ rs.close(); rs=null; } }catch(java.sql.SQLException e){ //do something System.out.println("Could not close the resultset"); } try { if(null!=st) { st.close(); st=null; } }catch(java.sql.SQLException e){ //do something System.out.println("Could not close the statement"); } try { if(null!=oConn) { oConn.close(); oConn=null; } }catch(java.sql.SQLException e){ //do something System.out.println("Could not close the connection"); } //Create the chart - Column 2D Chart with data from strXML chartCode=createChart("../../FusionCharts/Column2D.swf", "", strXML, "FactoryDetailed", 600, 300, false, false); } %> <%=chartCode%> <BR> <a href='Default.jsp?animate=0'>Back to Summary</a> <BR> </BODY> </HTML>
In this page, we're: Including FusionCharts.js JavaScript class and FusionCharts.jsp , to enable easy embedding of FusionCharts. Requesting the factory id for which we've to show detailed data. This data was sent to us as querystring, as a part of pie chart link. We get the requisite data for this factory from database and then convert it into XML using string concatenation. Finally, we create a Column 2D chart using createChart() method to show detailed data and render it. When you now run the app, you'll see the detailed page as under: