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October 03, 2003

cewolf charting is pretty cool

If you're looking for a web based charting library, check out cewolf at http://cewolf.sourceforge.net/

It's pretty cool, easy to use and appears to work fine with WAS 5.1 (this doesn't mean IBM supports it, just that I'm using it with no apparent problems). I haven't tried it with WAS 5.0 yet as I'm using an internal 5.1 driver for what I'm doing. I'm knocking an application together right now using struts 1.1 and this and it's working well. Easy to use and produces lots of nice shiny charts easily.

Check it out. Just follow the instructions in the tutorial to put it in a WAR and it seems to just work. I'll post more feedback as I use it more.

October 3, 2003 in Web/Tech | Permalink



I don not have a link to any document / tutorial which has some examples for knowing the way to use different tags. If you have explored something can you please share your exp with me.


Posted by: Biswakalyan | Nov 11, 2003 3:06:40 AM

I want to download cewolf s/w for making gantt chart.

Posted by: shubhangi | Feb 23, 2004 11:34:48 PM


I'm using cewolf with a struts 1.1 portlet on WPS 4.2 Extend, WAS 4.05. I get a 'message' instead of the charts: 'This chart has expired. Please reload.'

Running the same struts application as a Web Applicaton in local test server works as expected (WebSphere v4.0 Test Environment), WSAD 5.1.

Doesn't seem to be an error, nothing in WAS or WPS logs except standard cewolf debugging, just wondering if you encountered same.


Posted by: Michael Wall | Mar 4, 2004 1:14:33 PM

I have problems with cewolf, because, I can use show the graphics in my JSP when in it is under the root of my aplication:
- jsp_with_cewolf
But when it is in other directory.. like:
- jsp
-directory 1
-jsp_with_celf . It doesn't work... please... is there someone that want help me!.

Posted by: omar | Jun 1, 2004 10:53:45 AM

nice site. well done.

Posted by: jenny | Jun 8, 2004 4:55:35 AM

i enjoy being here. nice place.

Posted by: jenny | Jun 9, 2004 2:18:43 AM

i have a problem in cewolf, i worked throught the example thats given in the tutorial, but finally i am not able see the chart. the jsp page starts up and i can see all the data processing is done but i am not able to see the chart alone. in the tutorial it says if u have broken image, check your container's log files. what does this mean?

can anyone help me please

Posted by: praveen | Jul 11, 2004 3:46:24 PM

I have the gantt demo I working but cannot find the type for getting gantt II to render. I suppose that it will use the same data generation class, and just picture it using the rendering engine. Does anyone know the type to use to get gantt II to work?

Posted by: Mort Coleman | Jul 23, 2004 1:34:18 PM

It s good but i facing problem in using it with tiles and struts 1.1

Posted by: Mureed Alem | Aug 1, 2004 6:39:09 AM

I have discovered that is you move the jsp to a directory in webapps home the images are broken. However, if you put them in the webapps home directory they work. I found a fix...but am unsure if this is the correct way to handle this. But if you edit your *.jsp page and the line that says something like and change the renderer path to cewolf to something like
../cewolf then it worked. It seems the renderer parameter is a path to the cewolf "home" and cewolf "home" is your webapps root directory. So by changing the path in the renderer parameter I think you can fix the broken image problems. Oh, I have found the "Container logs" are in Tomcats logs directory.

Posted by: greg | Oct 22, 2004 10:30:50 AM

Is there a way to change or set the colors of the bars in gantt chart to something other than red or blue

Posted by: akshay | Nov 11, 2004 12:08:33 PM


I am having problems in generating charts with cewolf( using Weblogic server 8.1, struts 1.1) Works fine for few minutes and then start getting the below error message

'This chart has expired. Please reload.'

Posted by: anu | Jan 12, 2005 12:55:48 PM

i am getting this error when i run the tutorial application in my jbuilder 9

at de.laures.cewolf.taglib.tags.ChartImgTag.doStartTag

Posted by: muhammad ali | Feb 9, 2005 9:30:34 AM

I am having the same issue with the tutorial that CeWolf provides. I get the following exception:

at de.laures.cewolf.taglib.tags.ChartImgTag.doStartTag

Posted by: Joe S | Feb 22, 2005 9:45:52 AM

I am trying to generate a chart using cewolf in struts based application and I am badly stuck. I need to pass my form object to the produceDataset method to dynamically generate data for my chart. How in the field should I do it? Please heeeeeeeeeelllllpppp.... I have been stuck for last 2 days....

Posted by: smita | Apr 13, 2005 1:18:32 AM

Where should i set the map parameter which the produceDataset takes as input parameter?

Posted by: smita | Apr 13, 2005 2:59:01 AM


this is saritha from india,
i desperately seek for java api that generates charts using jsp.i need a free version. which i use it for my academics.i do my MCA final year(student)
i am using the following resources for my project
server: tomcat server
db: ms acess
technology: jsp,servelts
pls do reply for this


Posted by: saritha | Apr 26, 2005 11:36:26 PM

I am learning to use CEWolf!. I have followed the steps detailed in the tutorial to the last step. But I did not get any result worth the name!?!

Could somebody help me please?

Posted by: Satyanarayanan | Jan 19, 2006 2:41:35 AM

I have followed the steps given in the tutorial

But the following error message is displayed!

org.apache.jasper.JasperException: /web/index.jsp(25,4) Unable to load class chart

When I go into "index.jsp" line 25 col 4, this statement does not show any error

Could somebody help me please!?!

Posted by: Satyanarayanan | Jan 19, 2006 11:25:03 PM

I would like to know how to use the JDBCPieDataSet,JDBCCategoryDataset and JDBCXYDataset classes for charting purposes!?!

Could you mail me the step-by-step procedure?

Posted by: Satyanarayanan | Jan 31, 2006 11:05:48 PM

hi i want to use cewolf in my jsp application but dont know where to put the cewolf files on the server. plz if u could help my out.

Posted by: hiral | Feb 27, 2006 5:51:45 AM

Hi all,
Iam currently working on a project where we use Cewolf for generating charts. How do I change the colours of a bar graph manually ? It is displaying the bar graph with its own colours set by default. Its a bit urgent. Can someone help me on this ?

Posted by: Sharath | Mar 6, 2006 11:54:12 PM

I'm using cewolf to generate charts with JSP, Tomcat. The chart is getting plotted well only for the first time then on it displays only the same chart though the data is changed. to solve this i'm removing all session attributes(logout). Is there any other method to plot the chart with different data without logout?

Thanks a lot!

Posted by: Gopi | Mar 10, 2006 12:13:38 AM

Hey guys the problem got solved! I failed to see the hasExpired() method which was returning false!
Thanks anyway!
Have a good day!

Posted by: Gopi | Mar 10, 2006 12:46:06 AM

Hello, I am using Cewolf in my project and I am able to run the Tutorial Example, but now I want to show a pie chart and bar chart and its giving me ClassCaset Exception, can anybody please tell what code should go in the java classes which produces the dataset.

Posted by: pratap | May 22, 2006 2:18:56 AM

Is there any way to change colors of bars in StackedBarChart using CeWolf ?

Please let me know if there is a possibility ...


Posted by: Seshu | Jun 29, 2006 9:10:21 AM

As Mureed Alem mentioned earlier the broken links are because in the example jsp page the cewolf:img tag has renderer="cewolf" . So it is assuming the jsp page will be in your root folder. The solution is to specify the absolute path for the renedere i.e use renderer="/cewolf" in your cewolf:img tag.

To get different colors download the sample web app cewolfexample-1.0.war and look at their examples.

Posted by: MrCool | Sep 28, 2006 10:37:30 AM

I am totally new to charting.....
Can anybody provide the sample example for creating bar chart ?

Thanks in Advance :)

Posted by: Mangesh | Oct 5, 2006 9:24:14 AM

I am using cewolf for designing my charts.I am successful to that extent that I am able to show the data using single type of chart like eithere bar or line.But now my problem is I have to show the target as lline graph and values as Bargraph (in a single chart).If it was only Bar then i am able to do with two bars side by side.But i am not able to find any examples to embed line and barchart in as single chart.

Can u find any solution for this problem.If so please mail the solution asap so that it will be very much helpful to me.

Awaiting your reply

Thanks and regards,

Posted by: venugopal papasani | Dec 13, 2006 5:42:46 AM

Thanks a lot Gopi,
We were trying for changing the chart corresponding to our dynamic values..... Got it resolved by going through ur post... thanks a lot....

Posted by: Surya | Jan 25, 2007 4:36:40 AM

I am generating charts using cewolf.
I have to generate charts dynamically depends on user input values.Can i get some sample examples which generates charts dynamically.
Thank you.


Posted by: Amar | Feb 20, 2007 4:56:32 AM

I'm having a problem with cewolf using WebLogic Server

The same code runs right using Tomcat

The error in console is:
[ExecuteThread: '7' for queue: 'weblogic.kernel.Default'] ERROR tiles.InsertTag - ServletException in '/jsp/manageinsprealizadas/resresultadosinforme.jsp': null

Could anybody help me? Thanks

Posted by: David | Mar 7, 2007 5:07:14 AM

Thanks Mr Cool. I got your point.


Posted by: Uresh | Apr 18, 2007 11:16:36 AM


I want dynamic pie chart in Jsp.

i wrote code like this.


pageContext.setAttribute("pieData", pieData);


How to get this pieData dynamic value into servlet.

Posted by: Suganthi | May 5, 2007 1:38:17 AM

this is ravi from india,
i desperately seek for java api that generates charts using jsp.i need a free version. which i use it for my academics.i do my MCA final year(student)
i am using the following resources for my project
server: tomcat server
db: ms acess
technology: jsp,servelts
pls do reply for this


Posted by: ravi kumar | May 8, 2007 1:28:43 AM

I am facing same problem of 'This chart has expired. Please reload.'. What's the solution for this issue?
Kindly reply ASAP.

Posted by: Vijay | Jul 16, 2007 12:31:32 AM

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