Can't get upload from example to work in my program

[Patrick B Haggood]

I added FileUploadForm.java as a managed bean in my app which I call
from my upload form copied from UploadForm.jsp - when I click 'upload' I
get this error:

SEVERE: #{uploadController.upload}: javax.faces.el.EvaluationException:
java.lang.NullPointerException
javax.faces.FacesException: #{uploadController.upload}:
javax.faces.el.EvaluationException: java.lang.NullPointerException
        at
com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:78)
        at javax.faces.component.UICommand.broadcast(UICommand.java:312)

Further down the dump I see the offending line:
facesContext.getExternalContext().getApplicationMap().put("fileupload_bytes", 
_upFile.getBytes());

Why is this null?  Why, if upFile is bound to the inputText control on
the download form is this FacesContext gymnastics needed when my bean is
scopded 'session'?  

================================== uploadform.java
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import org.apache.myfaces.custom.fileupload.UploadedFile;
import javax.faces.context.FacesContext;
import java.io.*;

public class FileUploadForm
{
    private UploadedFile _upFile;
    private String _name = "";

    public UploadedFile getUpFile()
    {
        return _upFile;
    }

    public void setUpFile(UploadedFile upFile)
    {
        _upFile = upFile;
    }

    public String getName()
    {
        return _name;
    }

    public void setName(String name)
    {
        _name = name;
    }

    public String upload() throws IOException
    {
        System.out.println("Uploading");
        FacesContext facesContext = FacesContext.getCurrentInstance();

facesContext.getExternalContext().getApplicationMap().put("fileupload_bytes", 
_upFile.getBytes());

facesContext.getExternalContext().getApplicationMap().put("fileupload_type", 
_upFile.getContentType());

facesContext.getExternalContext().getApplicationMap().put("fileupload_name", 
_upFile.getName());
        System.out.println("file " + _upFile.getName());
        return null;
    }

    public boolean isUploaded()
    {
        FacesContext facesContext = FacesContext.getCurrentInstance();
        return
facesContext.getExternalContext().getApplicationMap().get("fileupload_bytes")!=null;
    }
    
    private void writeFile(UploadedFile uf) throws IOException {
        // create new trinityurldoc with original fname, type and desc,
return new filename in format FILE000n
        System.out.append("Writing file " + uf.getName());
        //String fname = appService.createNewFile(uf.getName(),
getUpFileDescription(), uf.getContentType());
                InputStream is = uf.getInputStream();
        FileOutputStream fos = new
FileOutputStream(uf.getName()); //defaultDir+fname);
        int c;
        while ((c = is.read()) != -1) {
            fos.write(c);
        }
    }

}

**************************** Upload form
        <h:panelGrid border="1" bgcolor="Aquamarine">
                <h:form id="uploadForm">
                        <h:outputText value="Upload" />
                    <x:inputFileUpload id="fileupload"
                                       accept="image/*"

value="#{uploadController.upFile}"
                                       storage="file"
                                       styleClass="fileUploadInput"
                                       required="true"/>
                        <h:outputText value="Description" />
                        <h:inputText value="#{uploadController.name}" />
                        <h:commandButton value="Upload"
                                action="#{uploadController.upload}" 
styleClass="button" />
                </h:form>

***************************** Facesconfig
        <managed-bean>
                <description>Upload Form</description>
                <managed-bean-name>uploadController</managed-bean-name>
                <managed-bean-class>
                        mateoweb.FileUploadForm
                </managed-bean-class>
                <managed-bean-scope>session</managed-bean-scope>
        </managed-bean>