PrimeFaces simple fileUpload: NullPointerException - jsf

Question

I try to make a simple fileupload so:
<h:form enctype="multipart/form-data">
<p:fileUpload value="#{catastrofes.file}" mode="simple"></p:fileUpload>
<p:separator/>
<h:commandButton value="Dummy Action" action="#{catastrofes.dummyAction}" ajax="false"></h:commandButton>
</h:form>
But when I submit, get file = null and raise NullPointerException, here a similar question, but the answer don't work for me, any ideas?
Here my managed bean:
import javax.faces.bean.ManagedBean;
import javax.faces.bean.RequestScoped;
import org.primefaces.model.UploadedFile;
#ManagedBean(name="catastrofes")
#RequestScoped
public class CatastrofesBean {
private UploadedFile file;
public String dummyAction() {
System.out.println("Uploaded File Name Is :: " + file.getFileName() + " :: Uploaded File Size :: " + file.getSize());
return "";
}
public UploadedFile getFile() {
return file;
}
public void setFile(UploadedFile file) {
this.file = file;
}
}
And my web.xml:
<context-param>
<param-name>primefaces.UPLOADER</param-name>
<param-value>auto|native|commons</param-value>
</context-param>
<filter>
<filter-name>Primefaces FileUpload Filter</filter-name>
<filter-class>
org.primefaces.webapp.filter.FileUploadFilter
</filter-class>
</filter>
<filter-mapping>
<filter-name>Primefaces FileUpload Filter</filter-name>
<servlet-name>Faces Servlet</servlet-name>
</filter-mapping>
Thanks!

Answer 1

According to primefaces_user_guide
auto: This is the default mode and PrimeFaces tries to detect the best method by checking the
runtime environment, if JSF runtime is at least 2.2 native uploader is selected, otherwise commons.
native: Native mode uses servlet 3.x Part API to upload the files and if JSF runtime is less than 2.2
and exception is being thrown.
commons: This option chooses commons fileupload regardless of the environment, advantage of
this option is that it works even on a Servlet 2.5 environment.
You should choose only one option not paste all those three options.
If you have commons-fileupload library in your project, I suggest you to choose commons.
in web.xml
<context-param>
<param-name>primefaces.UPLOADER</param-name>
<param-value>commons</param-value>
</context-param>
xhtml
<h:form enctype="multipart/form-data">
<p:growl id="messages" showDetail="true" />
<p:fileUpload value="#{fileUploadView.file}" mode="simple" />
<br /> <br />
<h:commandButton value="Dummy Action"
action="#{fileUploadView.upload}">
</h:commandButton>
</h:form>
managedbean
#ManagedBean
#RequestScoped
public class FileUploadView {
private UploadedFile file;
public UploadedFile getFile() {
return file;
}
public void setFile(UploadedFile file) {
this.file = file;
}
public void upload() {
System.out.println("Uploaded File Name Is :: " +
file.getFileName() +
" :: Uploaded File Size :: " + file.getSize());
if(file != null) {
FacesMessage message = new FacesMessage("Succesful", file.getFileName() + " is uploaded.");
FacesContext.getCurrentInstance().addMessage(null, message);
}
}
}