hi guys......i want to view a piechart extracting items from a mysql database. i've created a button on a jsp page(view.jsp) which is calling another jsp page(viewrst.jsp) when i click that. the code for (viewrst.jsp) is given below:
<%@ page language="java"%>
<%@page import="org.jfree.chart.*;"%>
<%@page import="java.sql.DriverManager;"%>
<%@page import="java.sql.*;"%>
<%@page import="org.jfree.data.jdbc.*;"%>
<%@page import="org.jfree.data.general.*;"%>
<%!
[B]public[/B] [B]class[/B] votepie {
/**
* @param args
*/
[B]private[/B] PieDataset readData() {
JDBCPieDataset data = [B]null[/B];
String url = "jdbc:mysql://localhost/vote";
Connection con;
[B]try[/B] {
Class.forName("com.mysql.jdbc.Driver");
}
[B]catch[/B] (ClassNotFoundException e) {
System.err.print("ClassNotFoundException: ");
System.err.println(e.getMessage());
}
[B]try[/B] {
con = DriverManager.getConnection(url, "vote", "vote001");
data = [B]new[/B] JDBCPieDataset(con);
String sql = "SELECT option_text, counter FROM VOTE_VOTES where poll_id=1;";
data.executeQuery(sql);
con.close();
}
[B]catch[/B] (SQLException e) {
System.err.print("SQLException: ");
System.err.println(e.getMessage());
}
[B]catch[/B] (Exception e) {
System.err.print("Exception: ");
System.err.println(e.getMessage());
}
[B]return[/B] data;
}
[B]public[/B] [B]static void[/B] main(String[] args) {
// TODO Auto-generated method stub
votepie pd = [B]new[/B] votepie();
pd.readData();
//creating the chart
JFreeChart chart = ChartFactory.createPieChart(
"Sample Pie Chart",
pd.readData(),
true, // legend?
true, // tooltips?
[B]false[/B] // URLs?
);
// create and display a frame...
ChartFrame frame = [B]new[/B] ChartFrame("First", chart);
frame.pack();
frame.setVisible([B]true[/B]);
}
}
%>& i'm getting this error when I click the button:
[B]HTTP Status 500 - [/B]
[B]type[/B] Exception report
[B]message[/B]
[B]description[/B] [U]The server encountered an internal error () that prevented it from fulfilling this request.[/U]
[B]exception[/B]
org.apache.jasper.JasperException: Unable to compile class for JSP:
An error occurred at line: 44 in the jsp file: /viewrst.jsp
The method main cannot be declared static; static methods can only be declared in a static or top level type
41: }
42: return data;
43: }
44: public static void main(String[] args) {
45: // TODO Auto-generated method stub
46:
47: votepie pd = new votepie();
Stacktrace:
org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:85)
org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:330)
org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:415)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:308)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:286)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:273)
org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:566)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:308)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
[B]note[/B] [U]The full stack trace of the root cause is available in the Apache Tomcat/6.0.10 logs.[/U]
[B]Apache Tomcat/6.0.10[/B]is the prob related to classpath variables?the java is working when i run it, but not in jsp. please suggest what to do?......thankz.
