This error usually happens when you forgot to declare the Tag Libraries in your Web project inside JDeveloper, just import the library (trough JSP Tag Libraries inside your IDE, I'm using JDeveloper here but I think that all of then uses the same concept) that references the attribute TAG and everything should compile. Hi all,Today I was working a lot only running the Application Module by itself.I had a View Object that I implemented its Java View Row Class. After some time I decided to change one attribute from "String" to "Number", running the AppModule again was giving me the exception:oracle.jbo.AttrValException: JBO-27019: The get method for attribute "attributeName" in "ViewObjectName" cannot be resolved.Bored of trying to solve the error I created a new VO based on the same EO. The new VO worked, so, I compared both of them (the new one and the old one), one difference of course is the RowImpl class, I implemented it on the new VO too moved my comparisons to the Java RowImpl class.This lead me to a strange IDE bug, after changing a Entity Attribute it does not refactor the ViewRowImpl class (I know it is too far for the IDE to know that kind of information but the fact is that it does not send us any intelligent messages about the error).Changing the bold word (getters and setters too of course) to my new data type worked as magic: MyVOAttribute { public Object get(MyVoRowImpl obj) { return obj.getMyVOAttribute(); } public void put(MyVoRowImpl obj, Object value) { obj.setMyVOAttribute((Number)value); } }For more information about JBO (Bussiness Componentes for Java) error messages read this:http://download.oracle.com/docs/cd/A97337_01/ias102_otn/buslog.102/bc4j/jboerrormessages.html#27019 Morning!When running a task-flow as a dialog do not forget to add those attributes to the button that calls the btf:useWindow="true" windowHeight="400" windowWidth="500"Without this you'll probably run into a 404 error, here is part of the exception (pt-BR message): <XmlHttpServletResponse> <_logException> javax.servlet.ServletException: ADF_FACES-60101:Codigo de Status de Erro de HTTP: 404." CORAL DA SAO LUCAS. ABRIL DE 2011.CASAMENTO DE CAROLINE E LUCIANOCASAMENTO DE LUCIANO E LUCIANEFORMATURA FERNANDO FERRARI1 ANINHO DE JOAO PEDRO15 ANOS DE BRUNNACASAMENTO DE DRIKA E CRISBATIZADO 14 DE MAIO DE 2011BATIZADO 29 DE MAIO DE 2011FESTA STEREO MIX NH HALL 10 DE JUNHO DE 2011 DECORACAO PARA GUARDANAPO DE PANO (fica preso no anel)DECORACAO PARA GUARDANAPO DE PANO (fica preso no anel) DECORACAO PARA GUARDANAPO DE PANO (fica preso no anel) TOPO DE PALITOTOPO DE PALITO A vida inteira de um insetoUm embriao pra virar fetoA folha do calendarioO trabalho pra ganhar o salario.Mas daqui a um mesQuando voce voltarA lua vai ta cheiaE no mesmo lugar...Se eu pudesse escolherOutra forma de serEu seria voce.E a saudade em mim agoraQuanto tempo sera que demoraUm mes pra passar?Flores nascem e morrem no jardimAssim o dia acaba em NoiteE o ceu parece nao ter fimEstrelas sempre mudam de lugarFazendo curvas no destinoAonde vai nos levarEu so queriaAcordar pra sempre com voceAte diriaQualquer coisa pra te convencerQue os dias passamAs pessoas mudamPor que e nao dificil acreditar em nos =)O nosso amor e tao palpavelQuando estamos sosA sua vozFaz o meu tempo pararEssa cara