Are you using and IDE with a debugger? If so have you tried setting a break point in your action to see what is happening? At least you should be able to throw in some logging or System.out.println statements.
I typically do not include a / in the action attribute of my html:form tag, but I have seen other include this so I guess it does not make much difference. You also don't need to specify the name and type attributes (and in fact these have been removed in newer releases of Struts).
Also, by default validation is enabled for actions, so if you do not need to perform validation, I would add a validate="false" attribute to my action definition in struts-config. If you do need to validate, then specify and input attribute. I think that if validation fails without an input attribute, you will see a blank page like you are describing.
BTW, this code [String target = new String("success")] is slightly less efficient than this code [String target = "success"].
Actually I've remembered to encounter this situation. You'd better first set validate="false" to try, because error in validation is one of the common reasons which result in blank page especally in struts.
I think you are trying this Example of the Wrox Publication books which returns a quote symbol's price...
Anywayz , I also had used this example and it did not give me any problems , Make sure that the <html:form> contains only 1 attribute i.e action="/LookUp", this is what is done on my machine. Also if somethings doesn't work dont keep a habit of Formatting the machine or the Appliction Server. Also just a small note which i would like you to be aware of. Whenever you make a single line of change or may be a small character is amended to struts-config.xml file it needs a restart of the Tomcat Server and in this case HOT DEPLOYMENT doesn't work.
Also as Brent suggested , Breakpoint in Eclipse 3.1 is a good option to debug the problem or perhaps the best way is to debug it using Log4J or CommonsLogging API from Apache.
Hope this post helps you troublshoot your query.
Thanks and Take Care Yogendra Joshi.
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