Generate JFreeChart in servlet
- by San4o
I'm trying to generate graphs using JFreeChart. I added record in web.xml, installed jfreechart library. Compiled servlet. Below code of servlet has shown:
import java.io.IOException;
import java.io.OutputStream;
import java.io.File;
import javax.servlet.*;
import javax.servlet.http.*;
import java.awt.Color;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartUtilities;
import org.jfree.chart.JFreeChart;
import org.jfree.data.general.DefaultPieDataset;
public class diagram extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doTestPieChart(request,response);
}
protected void doTestPieChart(HttpServletRequest request,
HttpServletResponse response)
throws IOException, ServletException
{
OutputStream out = response.getOutputStream();
try
{
DefaultPieDataset dataset = new DefaultPieDataset();
dataset.setValue("Graphic Novels", 192);
dataset.setValue("History", 125);
dataset.setValue("Military Fiction", 236);
dataset.setValue("Mystery", 547);
dataset.setValue("Performing Arts", 210);
dataset.setValue("Science, Non-Fiction", 70);
dataset.setValue("Science Fiction", 989);
JFreeChart chart = ChartFactory.createPieChart(
"Books by Type",
dataset,
true,
false,
false
);
chart.setBackgroundPaint(Color.white);
response.setContentType("image/png");
ChartUtilities.writeChartAsPNG(out, chart, 400, 300);
/*
ServletContext sc = getServletContext();
String filename = sc.getRealPath("pie.png");
File file = new File(filename);
ChartUtilities.saveChartAsPNG(file,chart,400,300);
*/
}
catch (Exception e)
{
System.out.println(e.toString());
}
finally
{
out.close();
}
}
}
When i launch the servlet, mistake has shown :
HTTP Status 500 -
type Exception report
message
description The server encountered an internal error () that prevented it from fulfilling this request.
exception
javax.servlet.ServletException: Error instantiating servlet class diagram
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:852)
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
java.lang.Thread.run(Thread.java:619)
root cause
java.lang.NoClassDefFoundError: org/jfree/data/general/PieDataset
java.lang.Class.getDeclaredConstructors0(Native Method)
java.lang.Class.privateGetDeclaredConstructors(Class.java:2389)
java.lang.Class.getConstructor0(Class.java:2699)
java.lang.Class.newInstance0(Class.java:326)
java.lang.Class.newInstance(Class.java:308)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:852)
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
java.lang.Thread.run(Thread.java:619)
root cause
java.lang.ClassNotFoundException: org.jfree.data.general.PieDataset
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1484)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1329)
java.lang.ClassLoader.loadClassInternal(ClassLoader.java:316)
java.lang.Class.getDeclaredConstructors0(Native Method)
java.lang.Class.privateGetDeclaredConstructors(Class.java:2389)
java.lang.Class.getConstructor0(Class.java:2699)
java.lang.Class.newInstance0(Class.java:326)
java.lang.Class.newInstance(Class.java:308)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:852)
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
java.lang.Thread.run(Thread.java:619)
note The full stack trace of the root cause is available in the Apache Tomcat/6.0.24 logs.
Help me to solve a problem. and where is problem?
