imagecropper with atribute image in primefaces doesn't crop although image is loaded - jsf

Question

if I change
image="#{pageContext.servletContext.contextPath}/upload
/#{fileUploadController.imagemTemporaria}"
and put
image="/imagens/#{fileUploadController.imagemTemporaria}"
the image is loaded. on the other hand, the method crop stops to work.
my images are in F:\imagens-retaguarda\imagens
my descriptor contains the following
<property name="alternatedocroot_1" value="from=/imagens/*
dir=F:\imagens-retaguarda\" />
do you know why that happens?
below is my code.
<h:form>
<p:outputPanel id="outputPanelUpload">
<h:panelGrid columns="2">
<h:outputText value="Imagem" rendered="#{fileUploadController.exibeBotao}"/>
<h:outputText value="Pré-visualização" rendered="#{fileUploadController.exibeBotao}"/>
<p:imageCropper id="imageCropperImagemTemporaria"
value="#{fileUploadController.croppedImage}"
image="#{pageContext.servletContext.contextPath}/upload/#{fileUploadController.imagemTemporaria}"
initialCoords="0,0,50,50"
maxSize="250,163"
minSize="30,30" />
<h:panelGroup rendered="#{fileUploadController.exibirPreVisualizacao}">
<p:graphicImage value="#{fileUploadController.imagemEnviada}" cache="false"/>
</h:panelGroup>
</h:panelGrid>
<br/>
<p:commandLink action="#{fileUploadController.crop}" update="outputPanelUpload" rendered="#{fileUploadController.exibeBotao}" value="Pré-visualizar" id="preVisualizar"/>
</p:outputPanel>
<br/>
<br/>
<p:fileUpload fileUploadListener="#{fileUploadController.enviarImagem}" sizeLimit="1000000" auto="true" update="outputPanelUpload" label="Escolher"/>
</h:form>

Answer 1

There is a restriction on p:imageCropper that it doesnt work with alternate docroot in glassfish
from primefaces forum
ImageCropper can crop local images in webroot and external images
located with http://. I don't think it is a bug but more like a
limitation as it doesn't support glassfish specific stuff like this.
link to above quoute by optimus.
Some friendly forum user has put together a codesnippet on how to construct the complete url. Havnt tested it myself, but conceptually it should work.
<p:imageCropper id="croppedImg"
value="#{controller.croppedImage}"
image="#{request.requestURL.substring(0, request.requestURL.length() - request.requestURI.length())}#{request.contextPath}/Screens/Image.png"
initialCoords="10,10,200,200" />
link