Advanced
Stacked Vertical Bar Graph, version 3.2
by Sirius Computer Consultants Limited
Connecting
the Graph to a Server Process
Both
the applet and servlet can be set to acquire the configuration
and graph data from a server side process/script. This is
done by simply entering the URL of the server side process
into the parameters of the bar graph. This method gives
the bar graph enormous flexibility in terms of data acquisition
and in the next section you will see how to use this method
to retrieve data from a database.
Creating
the Server Side Process
The server side process can be created in any language of
your choice and the only criteria is that the output must
follow the format of the data files (see Retrieving
Graph Data from files). To help you create your own
server side scripts we have created some template scripts
in the ServerTemplateScripts directory. We recommend using
these scripts as a starting point for your own.
Configuring
the Applet to use Server Side Scripts.
To set the applet to acquire data from a server process
simply, add the following parameters to your html, between
the <applet> and </applet> tags.
<PARAM
name="chartproperties" value="[URL of Server
Process]">
<PARAM name="chartdata" value="[URL of
Server Process]"
replacing
[URL of Server Process] with the URL of your server process.
For example if we have two java servlets (configServlet
and DataServlet) which create the config properties and
supply the graph data at url's,
http://www.jpowered.com/servlet/svConfigServlet
http://www.jpowered.com/servlet/DataServlet
then
the html parameters would be,
<PARAM
name="chartproperties" value="http://www.jpowered.com/servlet/svConfigServlet">
<PARAM name="chartdata" value="http://www.jpowered.com/servlet/DataServlet"
Configuring
the Servlet to use Server Side Scripts.
To
set the servlet to acquire data from a server process, simply
insert the url's of the server processes into the <IMG>
tag in your html page.
<img
src="[ServletEngineURL]/SVbarchartServlet?
config=[URLconfigFile]&
data=[URLdataFile]" width="500" height="420">
replacing
[URLconfigfile] and [URLdataFile] with the url's of your
server processes. For example if we have two java servlets
(configServlet and DataServlet) which create the config
properties and supply the graph data at url's,
http://www.jpowered.com/servlet/svConfigServlet
http://www.jpowered.com/servlet/DataServlet
then
the html <IMG> tag would be,
<img
src="http://www.jpowered.com/servlet/SVbarchartServlet?
config=http://www.jpowered.com/servlet/svConfigServlet&
data=http://www.jpowered.com/servlet/DataServlet" width="400"
height="300">
[