Best practice question for implementing a custom component

Question

I'm implementing a custom component which renders multiple <input type="text" .../> controls as part of it. The examples I've seen that do something similar use the ResponseWriter to generate the markup "by hand" like:
     writer.startElement("input", component);
     writer.writeAttribute("type", "text", null);
     writer.writeAttribute("id", "foo", null);
     writer.writeAttribute("name", "foo", null);
     writer.writeAttribute("value", "hello", null);
     writer.writeAttribute("size", "20", null);
     writer.endElement("input");
I don't know about anyone else, but I HATE having to write code that manufactures this stuff - seems to me that there are already classes that do this, so why not just use those? For example, the above could be replaced with:
     HtmlInputText textField = new HtmlInputText();
     textField.setId("foo");
     textField.setValue("hello");
     textField.setSize(20);
     // just to be safe, invoke both encodeBegin() and encodeEnd(),
     // though it seems like encodeEnd() actually does the work in this case,
     // but who knows if they might change it at some point
     textField.encodeBegin(context);
     textField.encodeEnd(context);
So my question is, why does everyone seem to favor the former over the latter? Why not leverage objects that already do the (encoding) work for you?

Answer 1

Got it!
You JSP should have this:
<h:panelGroup styleClass="jspPanel" id="jspPanel1"></h:panelGroup>
And your code page ValueChangeListener/ActionListner should have this:
          if (findComponent(getForm1(),"myOutputText") == null)
               FacesContext facesCtx = FacesContext.getCurrentInstance();
               System.out.println("Adding component");
               HtmlOutputText output =
                    (HtmlOutputText) facesCtx.getApplication().createComponent(
                         HtmlOutputText.COMPONENT_TYPE);
               output.setId("myOutputText");
               output.setValue("It works");
               getJspPanel1().getChildren().add(output);          
               System.out.println("Done");
               DebugUtil.printTree(FacesContext.getCurrentInstance().getViewRoot(),System.out);
          else
               System.out.println("component already added");
I just have to figure out this IOException on the closed stream - probably has to do with [immidiate="true"].
Thanks.
[9/15/04 13:05:53:505 EDT] 6e436e43 SystemErr R java.io.IOException: Stream closed
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at java.lang.Throwable.<init>(Throwable.java)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at java.lang.Throwable.<init>(Throwable.java)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at org.apache.jasper.runtime.JspWriterImpl.ensureOpen(JspWriterImpl.java:294)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at org.apache.jasper.runtime.JspWriterImpl.write(JspWriterImpl.java:424)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at org.apache.jasper.runtime.JspWriterImpl.write(JspWriterImpl.java:452)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.ibm.faces.component.UIJspPanel$ChildrenListEx.add(UIJspPanel.java:114)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at pagecode.admin.Test.handleListbox1ValueChange(Test.java)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at java.lang.reflect.AccessibleObject.invokeImpl(Native Method)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at java.lang.reflect.AccessibleObject.invokeV(AccessibleObject.java:199)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at java.lang.reflect.Method.invoke(Method.java:252)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.sun.faces.el.MethodBindingImpl.invoke(MethodBindingImpl.java:126)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at javax.faces.component.UIInput.broadcast(UIInput.java:492)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:284)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at javax.faces.component.UIViewRoot.processDecodes(UIViewRoot.java:342)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.sun.faces.lifecycle.ApplyRequestValuesPhase.execute(ApplyRequestValuesPhase.java:79)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.sun.faces.lifecycle.LifecycleImpl.phase(LifecycleImpl.java:200)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:90)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at javax.faces.webapp.FacesServlet.service(FacesServlet.java:197)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.servlet.StrictServletInstance.doService(StrictServletInstance.java:110)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.servlet.StrictLifecycleServlet._service(StrictLifecycleServlet.java:174)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.servlet.IdleServletState.service(StrictLifecycleServlet.java:313)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.servlet.StrictLifecycleServlet.service(StrictLifecycleServlet.java:116)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.servlet.ServletInstance.service(ServletInstance.java:283)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.servlet.ValidServletReferenceState.dispatch(ValidServletReferenceState.java:42)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.servlet.ServletInstanceReference.dispatch(ServletInstanceReference.java:40)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.webapp.WebAppRequestDispatcher.handleWebAppDispatch(WebAppRequestDispatcher.java:948)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.webapp.WebAppRequestDispatcher.dispatch(WebAppRequestDispatcher.java:530)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.webapp.WebAppRequestDispatcher.forward(WebAppRequestDispatcher.java:176)
[9/15/04 13:05:53:536 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.srt.WebAppInvoker.doForward(WebAppInvoker.java:79)
[9/15/04 13:05:53:552 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.srt.WebAppInvoker.handleInvocationHook(WebAppInvoker.java:201)
[9/15/04 13:05:53:552 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.cache.invocation.CachedInvocation.handleInvocation(CachedInvocation.java:71)
[9/15/04 13:05:53:552 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.srp.ServletRequestProcessor.dispatchByURI(ServletRequestProcessor.java:182)
[9/15/04 13:05:53:567 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.oselistener.OSEListenerDispatcher.service(OSEListener.java:334)
[9/15/04 13:05:53:567 EDT] 6e436e43 SystemErr R      at com.ibm.ws.webcontainer.http.HttpConnection.handleRequest(HttpConnection.java:56)
[9/15/04 13:05:53:567 EDT] 6e436e43 SystemErr R      at com.ibm.ws.http.HttpConnection.readAndHandleRequest(HttpConnection.java:610)
[9/15/04 13:05:53:567 EDT] 6e436e43 SystemErr R      at com.ibm.ws.http.HttpConnection.run(HttpConnection.java:435)
[9/15/04 13:05:53:567 EDT] 6e436e43 SystemErr R      at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:593)
[9/15/04 13:05:56:146 EDT] 6e436e43 SystemOut O Done