Hi Dusty, Thanks for the reply
On 21 Oct 2007 at 16:20, dusty wrote: > The secret to this problem is in the exception message "Error looking up > property .... in object type "java.lang.String" > > Since you are using struts use the <s:set /> tag to set the products List > OGNL variable to a JSTL variable. OK, this exposes the shallowness of my understanding of the underlying technologies. You've rightly pointed out I was using the JSTL c:set tag instead of the struts s:set tag. This occurred because I misread that part of the tutorial. I've only got a very superficial understanding of OGNL and specifically how it is used in AppFuse. I've since done a bit of googling around, looking at Struts/JSTL documentation and some of the AppFuse source but I still don't understand: 1. In the context of AppFuse what is the practical difference between c:set and s:set? In what kinds of scenarios would you use c:set instead of s:set and vice versa? 2. What things does AppFuse pre-load into OGNL (and/or other transient stores) prior to evaluating a JSP page and where does it do that? This might help me to understand why a POJO that uses the Generic DAO and Manager structures doesn't need a "<s:set " tag in their "pojoList.jsp" to expose the "getPojos" method. Maybe there are pages on appfuse.org that explain all this stuff, if so I'm sorry - please point me at them and I'll shut up for a while :-) > Also it the class of the objects in your list is String and not the Product > class you think you have. Please post > your DAO, Manager and Action code so we can see why you have Strings instead > of Products. Yes, that was how I also interpreted the error message. I've been back through the DAO, Manager and Action code specifically looking for the possibility that somewhere a list of Strings was being returned, but each of the relevant methods is definitly returning a List<Product>. I'm happy to post the code if it ends up being necessary, but I'm a bit reluctant to have other people wade through that stuff unnecessarily. > Rob Hills wrote: > > > > Hi All, > > > > I have a weird error on a Listing JSP that's had me stumped for several > > hours. > > > > I have a POJO named "Product" and have built associated ProductDao, > > ProductDaoHibernate, ProductManager, ProductManagerImpl > > and ProductAction classes, as well as tests for Dao, Manager and Action. > > I have a ProductList.jsp and I believe I've correctly configured all the > > "glue" bits (bean defninitions in applicationContext.xml, action > > definitions in struts.xml etc.). > > > > All tests pass OK and the web app starts up (Jetty + HSQLDB). > > > > However, when I go to view my products list, I get a blank page and the > > following error: > > > > [myapp] WARN [btpool0-1] LookupUtil.<init>(99) | Exception: [.LookupUtil] > > Error looking up property "id" in object type > > "java.lang.String". Cause: Unknown property 'id' > > java.lang.NoSuchMethodException: Unknown property 'id' > > at > > org.apache.commons.beanutils.PropertyUtilsBean.getSimpleProperty(PropertyUtilsBean.java:1122) > > at > > org.apache.commons.beanutils.PropertyUtils.getSimpleProperty(PropertyUtils.java:408) > > at org.displaytag.util.LookupUtil.getProperty(LookupUtil.java:271) > > at org.displaytag.util.LookupUtil.getBeanProperty(LookupUtil.java:129) > > at org.displaytag.model.Column.getValue(Column.java:124) > > at > > org.displaytag.model.Column.createChoppedAndLinkedValue(Column.java:201) > > at org.displaytag.model.Column.initialize(Column.java:178) > > at > > org.displaytag.render.TableWriterTemplate.writeTableBody(TableWriterTemplate.java:313) > > at > > org.displaytag.render.TableWriterTemplate.writeTable(TableWriterTemplate.java:138) > > at > > org.displaytag.render.HtmlTableWriter.writeTable(HtmlTableWriter.java:643) > > at org.displaytag.tags.TableTag.writeHTMLData(TableTag.java:1557) > > at org.displaytag.tags.TableTag.doEndTag(TableTag.java:1206) > > at > > org.apache.jsp.WEB_002dINF.pages.admin.productList_jsp._jspService(org.apache.jsp.WEB_002dINF.pages.admin.productList_jsp: > > 206) > > <.. lots more ..> > > > > Unfortunately, at no point does the stacktrace drop into any of my own > > classes, nor do any of my debug messages appear. > > > > The following snippet is from my ProductList.jsp: > > > > <c:set var="products" value="products" scope="request"/> > > <display:table name="products" class="table" requestURI="" > > id="productList" export="true" pagesize="25"> > > <display:column property="id" sortable="true" href="editProduct.html" > > media="html" > > paramId="id" paramProperty="id" titleKey="product.id"/> > > <display:column property="id" media="csv excel xml pdf" > > titleKey="product.id"/> > > <display:column property="name" sortable="true" > > titleKey="product.name"/> > > <.. lots more ..> > > > > My initial interpretation of the error message is that the "products" list > > being returned by the c:set line in the jsp is actually coming in as > > a list of strings and the server is complaining that the first String > > doesn't contain an ID (which it wouldn't of course). However, I've been > > back through my classes and the relevant methods are definitely returning > > List<Product>. > > > > The first line of my ProductAction.list() method is a log.debug call that > > never prints to the log so I'm at a loss to figure out what's going > > on. > > > > Has anyone else seen anything like this before? Any thoughts on what > > might be causing this problem, or where I should look? Thanks for all the help so far, Rob Hills Waikiki, Western Australia Mobile +61 (412) 904-357 Fax: +61 (8) 9529-2137 --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
