JSF 2.0 File upload
I am looking around a few blogs, to try to find how to upload files using JSF 2.0 But all the solutions kind of confuse me. I would like to know what do I 开发者_开发问答exactly need to be able to successfully upload a file(MP3, PDF, video... what ever type) and store it in a database as a @Lob. This is what I have done so far:
I created an entity that has an attribute of type byte[] and it is also annotated with a @Lob annotation.
I created an EJB that will introduce the entity with with a method that has a byte[] as a parameter and inserts it into the database using the EntityManager class( persist method).
I created a JSF page with an input tag of type "file" and a submit button
I prepared a managed bean to interchange information about the file with the JSF page.
Now I am stuck, and I have lots of doubts:
What should I do to pass the file from the JSF to the managed bean and then transform it to a byte[](To be able to handle it over to the EJB)?
How can a servlet help me?
Do I need a servlet to do this?
Also I found that in some blog it mentions something about servlets 3.0, but I don't know if my working environment is using it, how can if I am using servlets 3.0 (I am using JEE6)?
I never did file upload before and also I am not very familiar with servlets. I am confused, someone could give me some starting tips, please?
First of all, this (old) question and answer assumes JSF 2.0/2.1. Since JSF 2.2 there's a native <h:inputFile> component without the need for 3rd party component libraries. See also How to upload file using JSF 2.2 <h:inputFile>? Where is the saved File?
The easiest way would be using Tomahawk for JSF 2.0. It offers a <t:inputFileUpload> component.
Here's a step-by-step tutorial:
Create a blank dynamic web project for Servlet 3.0 and JSF 2.0. The
web.xmlmust comply Servlet 3.0 spec and already contain the JSF servlet:<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="YourProjectName" version="3.0"> <display-name>Your Project Name</display-name> <servlet> <servlet-name>Faces Servlet</servlet-name> <servlet-class>javax.faces.webapp.FacesServlet</servlet-class> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>Faces Servlet</servlet-name> <url-pattern>*.xhtml</url-pattern> </servlet-mapping> </web-app>The
faces-config.xmlmust comply JSF 2.0 spec:<?xml version="1.0" encoding="UTF-8"?> <faces-config xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-facesconfig_2_0.xsd" version="2.0"> </faces-config>Download Tomahawk 1.1.10 for JSF 2.0. Extract the zip file, go to the
/libfolder and copy all*.jarfiles into your/WEB-INF/lib.It are 18 files, of which
batik*.jarandxml*.jarare unnecessary for using alone thet:inputFileUploadcomponent. You could leave them away.Configure the Tomahawk extensions filter in
web.xml. It's the one who's responsible for handlingmultipart/form-datarequests which is required to be able to send files over HTTP.<filter> <filter-name>MyFacesExtensionsFilter</filter-name> <filter-class>org.apache.myfaces.webapp.filter.ExtensionsFilter</filter-class> </filter> <filter-mapping> <filter-name>MyFacesExtensionsFilter</filter-name> <servlet-name>Faces Servlet</servlet-name> </filter-mapping>Note that the
<servlet-name>must match the exact<servlet-name>of theFacesServletas you've definied inweb.xml.Create a simple Facelet,
upload.xhtml:<!DOCTYPE html> <html lang="en" xmlns="http://www.w3.org/1999/xhtml" xmlns:f="http://java.sun.com/jsf/core" xmlns:h="http://java.sun.com/jsf/html" xmlns:t="http://myfaces.apache.org/tomahawk" xmlns:ui="http://java.sun.com/jsf/facelets"> <h:head> <title>Tomahawk file upload demo</title> </h:head> <h:body> <h:form enctype="multipart/form-data"> <t:inputFileUpload value="#{bean.uploadedFile}" /> <h:commandButton value="submit" action="#{bean.submit}" /> <h:messages /> </h:form> </h:body> </html>Note the
enctype="multipart/form-data"attribute on<h:form>, this is very important in order to be able to send files with HTTP.Create a simple managed bean,
com.example.Bean:package com.example; import java.io.IOException; import javax.faces.application.FacesMessage; import javax.faces.bean.ManagedBean; import javax.faces.bean.RequestScoped; import javax.faces.context.FacesContext; import org.apache.commons.io.FilenameUtils; import org.apache.myfaces.custom.fileupload.UploadedFile; @ManagedBean @RequestScoped public class Bean { private UploadedFile uploadedFile; public void submit() throws IOException { String fileName = FilenameUtils.getName(uploadedFile.getName()); String contentType = uploadedFile.getContentType(); byte[] bytes = uploadedFile.getBytes(); // Now you can save bytes in DB (and also content type?) FacesContext.getCurrentInstance().addMessage(null, new FacesMessage(String.format("File '%s' of type '%s' successfully uploaded!", fileName, contentType))); } public UploadedFile getUploadedFile() { return uploadedFile; } public void setUploadedFile(UploadedFile uploadedFile) { this.uploadedFile = uploadedFile; } }
That should be it. Open it by http://localhost:8080/projectname/upload.xhtml.
As to your concrete questions:
what should i do to pass the file from the JSF to the managed bean and then transform it to a byte[](To be able to handle it over to the EJB)?
This is answered above.
How can a servlet help me?
It is able to process and control HTTP requests/responses. In a JSF environment, the FacesServlet already does all the work.
Do i need a servlet to do this?
In a JSF environment, the FacesServlet is mandatory. But it's already provided by the API, you don't need to write one yourself. However, to be able to download files from a database, another servlet is definitely useful. You can find a basic example here: Servlet for serving static content.
Also i found that in some blog it mentions something about servlets 3.0, but i dont know if my working enviroment is ussing it, how can if i am ussing servlets 3.0(I am ussing JEE6)?
If you're using Servlet 3.0 container like Glassfish 3, JBoss AS 6, Tomcat 7, etc and the web.xml is declared as Servlet 3.0, then you're definitely using Servlet 3.0. Servlet 3.0 is part of Java EE 6.
For completeness, I just want to provide a fully functional self contained example of how this is done with JSF 2.2, either with non-Ajax and Ajax requests. Keep in mind JSF 2.2 uses different namespaces and you need to be working with a Servlet 3.0 container (as Tomcat 7.0.x, JBoss AS 6.x and 7.x and GlassFish 3.x are).
fileUpload.xhtml
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://xmlns.jcp.org/jsf/html"
xmlns:f="http://xmlns.jcp.org/jsf/core">
<h:head />
<h:body>
<h:form enctype="multipart/form-data">
<h:inputFile value="#{uploadBean.file}" />
<h:commandButton value="Post Upload" action="#{uploadBean.upload}" />
</h:form>
<h:form enctype="multipart/form-data">
<h:inputFile value="#{uploadBean.file}" />
<h:commandButton value="Ajax Upload">
<f:ajax listener="#{uploadBean.upload}" execute="@form"
render="countOutput" />
</h:commandButton>
<!-- Counts the uploaded items -->
<h:outputText id="countOutput"
value="Files uploaded #{uploadBean.filesUploaded}" />
</h:form>
</h:body>
</html>
UploadBean.java:
@ManagedBean
@ViewScoped
public class UploadBean {
private int filesUploaded = 0;
//javax.servlet.http.Part (Servlet 3.0 API)
private Part file;
private String fileContent;
/**
* Just prints out file content
*/
public void upload() {
try {
fileContent = new Scanner(file.getInputStream())
.useDelimiter("\\A").next();
System.out.println(fileContent + " uploaded");
filesUploaded++;
} catch (IOException e) {
e.printStackTrace();
}
}
public int getFilesUploaded() {
return filesUploaded;
}
public Part getFile() {
return file;
}
public void setFile(Part file) {
this.file = file;
}
}
See also:
- JSF 2.2: File upload with h:inputFile
I would recommend using a companent library like Tomahawk's <t:inputFileUpload> or PrimeFaces <p:fileUpload>.
BalusC also has a nice blog post about Uploading files with JSF 2.0 and Servlet 3.0.
BalusC's blog post: Uploading files with JSF 2.0 and Servlet 3.0 is what saved me, because I had problems running RichFaces 4 fileUpload tag with Spring WebFlow.
It's worth to modify BalusC's code to use Spring's MultipartResolver - you don't need his MultipartMap from another blog post.
I achieved it by modifying a decode method in FileRenderer like this:
UploadedFile ret = null;
Object req = context.getExternalContext().getRequest();
if (req instanceof MultipartHttpServletRequest) {
MultipartFile file = ((MultipartHttpServletRequest)req).getFile(clientId);
File temp = null;
try {
temp = File.createTempFile("_UPLOAD_", null);
file.transferTo(temp);
String name = new File(file.getOriginalFilename()).getName();
ret = new UploadedFile(temp, name);
} catch (IOException e) {
throw new RuntimeException("Could not create temp file.", e);
}
} else {
throw new IllegalStateException("Request is not multipart. Use spring's multipart resolver.");
}
// If no file is specified, set empty String to trigger validators.
((UIInput) component).setSubmittedValue( ret == null ? EMPTY_STRING : ret);
A UploadedFile is a simple serializable POJO used to return results to backing bean.
In JSF 2.2 you can easily upload file using tag without using commons-io or filter. This tag support both normal and ajax process.
Normal:
<h:inputFile id="file" value="#{fileUploadBean.uploadedFile}"/>
<h:commandButton id="button" action="#{fileUploadBean.sumbit()}" value="Upload"/>
Ajax:
<h:inputFile id="file" value="#{fileUploadBean.uploadedFile}"/>
<h:commandButton id="button" value="submit">
<f:ajax execute="@all" render="@all" onevent="statusUpdate"/>
</h:commandButton>
Design your managed bean as follows:
@Named
@RequestScoped
public class FileUploadBean {
private Part uploadedFile;
}
The easiest way is probably to use the inputFileUpload tag that you can find in MyFaces:
http://myfaces.apache.org/
IceFaces2.0 has one, http://wiki.icefaces.org/display/ICE/FileEntry Haven't tried implementing it yet, but the download has sample apps and it works under Tomcat 6 (servlet 2.5, so not JEE6)
You must add commons-fileupload-1.2.1.jar in our project Build Path
1.Configure web.xml file:
Web.xml
<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>
<mime-mapping>
<extension>png</extension>
<mime-type>image/png</mime-type>
</mime-mapping>
2. Create ManagedBean
@ManagedBean
@SessionScoped
public class FileUploadBean implements Serializable{
public FileUpload (){
}
private StreamedContent file;
public void loadFile(FileUploadEvent event) throws IOException, InterruptedException {
InputStream input = new ByteArrayInputStream(event.getFile().getContents());
file= new DefaultStreamedContent(input, "image/jpg");
}
}
3.jsf file(xhtml)
<h:form enctype="multipart/form-data">
<p:fileUpload fileUploadListener="#{fileUploadBean.file}" sizeLimit="100000" allowTypes="/(\.|\/)(gif|jpe?g|png|bmp)$/"/>
</h:form>
加载中,请稍侯......
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