WebChart. java Package net. sentom. chart;
Import java. awt. Insets;
Import java. awt. Font;
Import java. io. PrintWriter;
Import javax. servlet. http. HttpSession;
Import org. jfree. data .*;
Import org. jfree. chart .*;
Import org. jfree. chart. plot .*;
Import org. jfree. chart. entity .*;
Import org. jfree. chart. urls .*;
Import org. jfree. chart. servlet .*;
Import org. jfree. chart. labels. StandardPieToolTipGenerator;
/**
* @ Author sentom
*
* To change the template for this generated type comment go
* Window> Preferences> Java> Code Generation> Code and Comments
*/
Public class WebChart {
Private defapipiedataset data = new DefaultPieDataset ();
Public void setValue (String key, double value ){
Data. setValue (key, value );
}
Public String generatePieChart (String title, HttpSession session, PrintWriter pw ){
String filename = null;
Try {
// Create a chart object
PiePlot plot = new PiePlot (data );
Plot. setInsets (new Insets (0, 5, 5, 5 ));
// Create a link on the statistical Image
Plot. setURLGenerator (new StandardPieURLGenerator ("link. jsp", "section "));
Plot. setToolTipGenerator (new StandardPieToolTipGenerator ());
JFreeChart chart = new JFreeChart ("", JFreeChart. DEFAULT_TITLE_FONT,
Plot, true );
Chart. setBackgroundPaint (java. awt. Color. white); // you can specify the background Color of an image.
Font font = new Font ("", Font. CENTER_BASELINE, 20); // set the Font of the image title
And size
TextTitle _ title = new TextTitle (title );
_ Title. setFont (font );
Chart. setTitle (_ title );
// Put the generated image in a temporary directory
ChartRenderingInfo info = new ChartRenderingInfo (new
StandardEntityCollection ());
// 500 indicates the image length and 300 indicates the image height.
Filename = ServletUtilities. saveChartAsPNG (chart, 500,300, info,
Session );
ChartUtilities. writeImageMap (pw, filename, info );
Pw. flush ();
} Catch (Exception e ){
System. out. println ("Exception-" + e. toString ());
E. printStackTrace (System. out );
Filename = "public_error_500x300.png ";
}
Return filename;
}
}
JSP file
<% @ Page contentType = "text/html; charset = GBK" %>
<% @ Page import = "java. io. PrintWriter" %>
<% @ Page import = "net. sentom. chart. WebChart" %>
<%
WebChart chart = new WebChart ();
Chart. setValue ("June", 500 );
Chart. setValue ("July", 580 );
Chart. setValue ("August", 828 );
String filename = chart. generatePieChart ("www.111cn.net website access statistics table", session, new
PrintWriter (out ));
String graphURL = request. getContextPath () + "/servlet/DisplayChart? Filename = "+ filename;
%>
<HTML>
<HEAD>
<TITLE> www.sentom.net </TITLE>
</HEAD>
<BODY>
<P align = "CENTER">
" width = 500 height = 300 border = 0 usemap = "# <% =
Filename %> ">
</P>
</BODY>
</HTML> |
