As soon as I add the librarys icefaces.jar icepush.jar icefaces_ace.jar to my classpath in order to use ACE components, my SaveAs dialog won't popup? I'm not sure if this is a bug but without the librarys in classpath it works. Here's my save as method :
public void downloadFile(String propertyPath) throws IOException {
ProxyFile fileToDownload = repBean.downloadFile(propertyPath);
FacesContext facesContext = FacesContext.getCurrentInstance();
ExternalContext externalContext = facesContext.getExternalContext();
HttpServletResponse response = (HttpServletResponse) externalContext.getResponse();
response.reset(); response.setContentType(fileToDownload.getContentType());
response.setHeader("Content-Length", String.valueOf(fileToDownload.getLength()));
response.setHeader("Content-disposition", "attachment; filename=\"" + fileToDownload.getName() + "\"");
BufferedInputStream input = null;
BufferedOutputStream output = null;
try {
input = new BufferedInputStream(fileToDownload.getContent());
output = new BufferedOutputStream(response.getOutputStream());
byte[] buffer = new byte[10240];
for (int length; (length = input.read(buffer)) > 0;) {
output.write(buffer, 0, length);
}
} finally {
output.close();
input.close();
facesContext.responseComplete();
}
}
You can't download files using ajax.
Ajax is under the covers executed by JavaScript's XMLHttpRequest object. The request will be successfully executed and the response will be successfully retrieved. However, JavaScript has no facility to write the response to client's disk file system, nor to force a Save As dialogue with the given response. That would be a huge security breach.
The cause of your concrete problem is ICEfaces itself. Namely, when you integrate ICEfaces in a JSF web application, all standard <h:commandXxx> links/buttons will silently be turned into ajax-enabled ones which indeed causes confusion among starters. Make sure that the download link/button isn't implicitly using ICEfaces-introduced ajax facility. As per their wiki page on the subject, you need to explicitly nest a <f:ajax disabled="true"> to disable this.
Disable Ajax for a Component
You can also disable Ajax at the level of the individual component:
<h:commandButton value="Send" actionListener="#{bean.sendMessage}">
<f:ajax disabled="true"/>
</h:commandButton>
Apply it on your download link/button.
Is there any way of providing a file download from a JSF backing bean action method?
I have tried a lot of things. Main problem is that I cannot figure how to get the OutputStream of the response in order to write the file content to. I know how to do it with a Servlet, but this cannot be invoked from a JSF form and requires a new request.
How can I get the OutputStream of the response from the current FacesContext?
Introduction
You can get everything through ExternalContext. In JSF 1.x, you can get the raw HttpServletResponse object by ExternalContext#getResponse(). In JSF 2.x, you can use the bunch of new delegate methods like ExternalContext#getResponseOutputStream() without the need to grab the HttpServletResponse from under the JSF hoods.
On the response, you should set the Content-Type header so that the client knows which application to associate with the provided file. And, you should set the Content-Length header so that the client can calculate the download progress, otherwise it will be unknown. And, you should set the Content-Disposition header to attachment if you want a Save As dialog, otherwise the client will attempt to display it inline. Finally just write the file content to the response output stream.
Most important part is to call FacesContext#responseComplete() to inform JSF that it should not perform navigation and rendering after you've written the file to the response, otherwise the end of the response will be polluted with the HTML content of the page, or in older JSF versions, you will get an IllegalStateException with a message like getoutputstream() has already been called for this response when the JSF implementation calls getWriter() to render HTML.
Turn off ajax / don't use remote command!
You only need to make sure that the action method is not called by an ajax request, but that it is called by a normal request as you fire with <h:commandLink> and <h:commandButton>. Ajax requests and remote commands are handled by JavaScript which in turn has, due to security reasons, no facilities to force a Save As dialogue with the content of the ajax response.
In case you're using e.g. PrimeFaces <p:commandXxx>, then you need to make sure that you explicitly turn off ajax via ajax="false" attribute. In case you're using ICEfaces, then you need to nest a <f:ajax disabled="true" /> in the command component.
Generic JSF 2.x example
public void download() throws IOException {
FacesContext fc = FacesContext.getCurrentInstance();
ExternalContext ec = fc.getExternalContext();
ec.responseReset(); // Some JSF component library or some Filter might have set some headers in the buffer beforehand. We want to get rid of them, else it may collide.
ec.setResponseContentType(contentType); // Check http://www.iana.org/assignments/media-types for all types. Use if necessary ExternalContext#getMimeType() for auto-detection based on filename.
ec.setResponseContentLength(contentLength); // Set it with the file size. This header is optional. It will work if it's omitted, but the download progress will be unknown.
ec.setResponseHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\""); // The Save As popup magic is done here. You can give it any file name you want, this only won't work in MSIE, it will use current request URL as file name instead.
OutputStream output = ec.getResponseOutputStream();
// Now you can write the InputStream of the file to the above OutputStream the usual way.
// ...
fc.responseComplete(); // Important! Otherwise JSF will attempt to render the response which obviously will fail since it's already written with a file and closed.
}
Generic JSF 1.x example
public void download() throws IOException {
FacesContext fc = FacesContext.getCurrentInstance();
HttpServletResponse response = (HttpServletResponse) fc.getExternalContext().getResponse();
response.reset(); // Some JSF component library or some Filter might have set some headers in the buffer beforehand. We want to get rid of them, else it may collide.
response.setContentType(contentType); // Check http://www.iana.org/assignments/media-types for all types. Use if necessary ServletContext#getMimeType() for auto-detection based on filename.
response.setContentLength(contentLength); // Set it with the file size. This header is optional. It will work if it's omitted, but the download progress will be unknown.
response.setHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\""); // The Save As popup magic is done here. You can give it any file name you want, this only won't work in MSIE, it will use current request URL as file name instead.
OutputStream output = response.getOutputStream();
// Now you can write the InputStream of the file to the above OutputStream the usual way.
// ...
fc.responseComplete(); // Important! Otherwise JSF will attempt to render the response which obviously will fail since it's already written with a file and closed.
}
Common static file example
In case you need to stream a static file from the local disk file system, substitute the code as below:
File file = new File("/path/to/file.ext");
String fileName = file.getName();
String contentType = ec.getMimeType(fileName); // JSF 1.x: ((ServletContext) ec.getContext()).getMimeType(fileName);
int contentLength = (int) file.length();
// ...
Files.copy(file.toPath(), output);
Common dynamic file example
In case you need to stream a dynamically generated file, such as PDF or XLS, then simply provide output there where the API being used expects an OutputStream.
E.g. iText PDF:
String fileName = "dynamic.pdf";
String contentType = "application/pdf";
// ...
Document document = new Document();
PdfWriter writer = PdfWriter.getInstance(document, output);
document.open();
// Build PDF content here.
document.close();
E.g. Apache POI HSSF:
String fileName = "dynamic.xls";
String contentType = "application/vnd.ms-excel";
// ...
HSSFWorkbook workbook = new HSSFWorkbook();
// Build XLS content here.
workbook.write(output);
workbook.close();
Note that you cannot set the content length here. So you need to remove the line to set response content length. This is technically no problem, the only disadvantage is that the enduser will be presented an unknown download progress. In case this is important, then you really need to write to a local (temporary) file first and then provide it as shown in previous chapter.
Utility method
If you're using JSF utility library OmniFaces, then you can use one of the three convenient Faces#sendFile() methods taking either a File, or an InputStream, or a byte[], and specifying whether the file should be downloaded as an attachment (true) or inline (false).
public void download() throws IOException {
Faces.sendFile(file, true);
}
Yes, this code is complete as-is. You don't need to invoke responseComplete() and so on yourself. This method also properly deals with IE-specific headers and UTF-8 filenames. You can find source code here.
public void download() throws IOException
{
File file = new File("file.txt");
FacesContext facesContext = FacesContext.getCurrentInstance();
HttpServletResponse response =
(HttpServletResponse) facesContext.getExternalContext().getResponse();
response.reset();
response.setHeader("Content-Type", "application/octet-stream");
response.setHeader("Content-Disposition", "attachment;filename=file.txt");
OutputStream responseOutputStream = response.getOutputStream();
InputStream fileInputStream = new FileInputStream(file);
byte[] bytesBuffer = new byte[2048];
int bytesRead;
while ((bytesRead = fileInputStream.read(bytesBuffer)) > 0)
{
responseOutputStream.write(bytesBuffer, 0, bytesRead);
}
responseOutputStream.flush();
fileInputStream.close();
responseOutputStream.close();
facesContext.responseComplete();
}
This is what worked for me:
public void downloadFile(String filename) throws IOException {
final FacesContext fc = FacesContext.getCurrentInstance();
final ExternalContext externalContext = fc.getExternalContext();
final File file = new File(filename);
externalContext.responseReset();
externalContext.setResponseContentType(ContentType.APPLICATION_OCTET_STREAM.getMimeType());
externalContext.setResponseContentLength(Long.valueOf(file.lastModified()).intValue());
externalContext.setResponseHeader("Content-Disposition", "attachment;filename=" + file.getName());
final HttpServletResponse response = (HttpServletResponse) externalContext.getResponse();
FileInputStream input = new FileInputStream(file);
byte[] buffer = new byte[1024];
final ServletOutputStream out = response.getOutputStream();
while ((input.read(buffer)) != -1) {
out.write(buffer);
}
out.flush();
fc.responseComplete();
}
This is my solution, an extension of BalusC's answer
public static void download(
ByteArrayOutputStream baos,
String downloadFileName,
String contentType
) {
FacesContext context = FacesContext.getCurrentInstance();
ExternalContext externalContext = context.getExternalContext();
externalContext.responseReset();
HttpServletResponse response = (HttpServletResponse) externalContext.getResponse();
response.reset();
response.setContentType(contentType);
response.setHeader("Expires", "0");
response.setHeader("Cache-Control", "must-revalidate, post-check=0, pre-check=0");
response.setHeader("Pragma", "public");
Integer size = baos.size();
response.setHeader("Content-Length", size.toString());
response.setHeader(
"Content-Disposition",
"attachment; filename=\"" + downloadFileName + "\""
);
try {
try (OutputStream responseOs = response.getOutputStream()) {
baos.writeTo(responseOs);
}
}
catch (IOException e) {
throw new IOUncheckedException(e);
}
context.responseComplete();
}
here is the complete code snippet http://bharatonjava.wordpress.com/2013/02/01/downloading-file-in-jsf-2/
#ManagedBean(name = "formBean")
#SessionScoped
public class FormBean implements Serializable
{
private static final long serialVersionUID = 1L;
/**
* Download file.
*/
public void downloadFile() throws IOException
{
File file = new File("C:\\docs\\instructions.txt");
InputStream fis = new FileInputStream(file);
byte[] buf = new byte[1024];
int offset = 0;
int numRead = 0;
while ((offset < buf.length) && ((numRead = fis.read(buf, offset, buf.length -offset)) >= 0))
{
offset += numRead;
}
fis.close();
HttpServletResponse response =
(HttpServletResponse) FacesContext.getCurrentInstance()
.getExternalContext().getResponse();
response.setContentType("application/octet-stream");
response.setHeader("Content-Disposition", "attachment;filename=instructions.txt");
response.getOutputStream().write(buf);
response.getOutputStream().flush();
response.getOutputStream().close();
FacesContext.getCurrentInstance().responseComplete();
}
}
You may change the file reading logic in case you want file to get generated at runtime.
i use Primefaces 3.0.1 and build up a menubar with programmatically filled model. I need some Links like depotDetails.xhtml?id=1 But if i use these URL for my menuitem
item.setUrl("depotDetail.xhtml?id=1"); // that dont work
so i tried to add an ActionListener:
FacesContext facesContext = FacesContext.getCurrentInstance();
ValueExpression target = facesContext.getApplication().getExpressionFactory().createValueExpression(FacesContext.getCurrentInstance().getELContext(), "#{DepotBean.currentDepot}",String.class);
ValueExpression value = facesContext.getApplication().getExpressionFactory().createValueExpression(FacesContext.getCurrentInstance().getELContext(), "ehnemeneee",String.class);
ActionListener handler = new SetPropertyActionListenerImpl(target, value);
item.addActionListener(handler);
but that also dont work. Can anybody help?
Greets Thomas
I got a solution ... but is it the right way?
// building the menu model ..
UIParameter param = null;
for(Depots testdepot: depotList){
param = new UIParameter();
param.setName("currentDepotId");
param.setValue(testdepot.getIdDepot());
item = new MenuItem();
item.setValue(testdepot.getDepotName());
// calling menuListener
item.addActionListener(new MenuListener());
item.setUpdate("messages");
item.setId("menuItemDepot"+testdepot.getIdDepot());
item.getChildren().add(param);
submenu.getChildren().add(item);
}
// MenuListener
public void processAction(ActionEvent event) throws AbortProcessingException {
FacesContext fc = FacesContext.getCurrentInstance();
HttpServletRequest request = (HttpServletRequest) fc.getExternalContext().getRequest();
HttpSession session = (HttpSession) fc.getExternalContext().getSession(false);
// get param id
String name = (String) event.getComponent().getAttributes().get("currentDepotId");
// set session var
session.setAttribute("currentDepotId", name);
fc.getExternalContext().redirect(request.getContextPath() + "/userarea/depotDetail.xhtml");
}
// read the session in the depot bean
FacesContext fc = FacesContext.getCurrentInstance();
HttpSession session = (HttpSession) fc.getExternalContext().getSession(false);
String currentDepotId = session.getAttribute("currentDepotId");
I'm trying to generate a simple PDF report using JasperReport on a button click. Here's the relevant code:
report.xhtml:
<p:commandButton value="#{msg['report.generate']}" action="#{generateReportBean.generateReport}" />
GenerateReportBean.java:
public void generateReport() throws JRException, IOException {
FacesContext facesContext = FacesContext.getCurrentInstance();
ExternalContext externalContext = facesContext.getExternalContext();
HttpServletResponse response = (HttpServletResponse) externalContext
.getResponse();
InputStream reportStream = facesContext.getExternalContext().getResourceAsStream("/WEB-INF/reports/report.jrxml");
JasperDesign jasperDesign = JRXmlLoader.load(reportStream);
JasperReport jasperReport = JasperCompileManager.compileReport(jasperDesign);
byte[] report = JasperRunManager.runReportToPdf(jasperReport, new HashMap(), new JREmptyDataSource());
response.setContentType("application/pdf");
response.setContentLength(report.length);
response.setHeader("Content-disposition", "attachment; filename=report.pdf" );
ServletOutputStream servletOutputStream = response.getOutputStream();
servletOutputStream.write(report);
servletOutputStream.flush();
servletOutputStream.close();
facesContext.responseComplete();
}
The problem is that when I use FireBug I can see a response (for me it's ok):
X-Powered-By JSF/2.0
Content-Type application/pdf
Content-Length 1310
Content-Disposition attachment; filename=report.pdf
Server Jetty(7.4.0.v20110414)
But I don't get the popup that would allow me to save the pdf. As you can see I'm developing on Jetty 7.4 maven plugin. Am I doing something wrong here?
Add ajax="false" to your commandButton
<p:commandButton ajax="false" value="#{msg['report.generate']}" action="#{generateReportBean.generateReport}" />
I'm trying to use http://code.google.com/p/kaptcha/ which looks like a very easy way to include CAPTCHA. My demo app is JSF and although the instructions are simple for JSP, I don't know how to use them in JSF. How do I translate this in JSF?
In your code that manages the submit action:
String kaptchaExpected = (String)request.getSession()
.getAttribute(com.google.code.kaptcha.Constants.KAPTCHA_SESSION_KEY);
String kaptchaReceived = request.getParameter("kaptcha");
if (kaptchaReceived == null || !kaptchaReceived.equalsIgnoreCase(kaptchaExpected))
{
setError("kaptcha", "Invalid validation code.");
}
I tried putting it in my:
public String button1_action() {
// TODO: Process the action.
return "success";
}
but it doesn't understand the request object :(
This equivalent JSF action should do it:
// bind to <h:inputText value="#{thisbean.kaptchaReceived}" />
private String kaptchaReceived;
public String getKaptchaReceived() {
return kaptchaReceived;
}
public void setKaptchaReceived(String kaptcha) {
kaptchaReceived = kaptcha;
}
public String button1_action() {
if (kaptchaReceived != null) {
FacesContext context = FacesContext
.getCurrentInstance();
ExternalContext ext = context.getExternalContext();
Map<String, Object> session = ext.getSessionMap();
String kaptchaExpected = session
.get(com.google.code.kaptcha.Constants.KAPTCHA_SESSION_KEY);
if (kaptchaReceived.equalsIgnoreCase(kaptchaExpected)) {
return "success";
}
}
return "problem";
}
This assumes that you want to use h:inputText and h:graphicImage in your JSF view instead of HTML elements.
Implementing validator is another easy way to validate the kaptcha.
<h:inputText id="kaptcha" autocomplete="off" required="true">
<f:validator validatorId="kaptchaValidator" />
</h:inputText>
<h:message for="kaptcha" styleClass="errorMessage"/>
--- Validator ---
public class KaptchaValidator implements Validator {
#Override
public void validate(FacesContext facesContext, UIComponent uiComponent, Object value) throws ValidatorException {
HttpSession session = (HttpSession) facesContext.getExternalContext().getSession(true);
String kaptchaExpected = (String) session.getAttribute(com.google.code.kaptcha.Constants.KAPTCHA_SESSION_KEY);
String kaptchaReceived = (String) value;
if (kaptchaReceived == null || !kaptchaReceived.equalsIgnoreCase(kaptchaExpected)) {
FacesMessage message = new FacesMessage();
message.setDetail("Invalid Security Code.");
message.setSummary("Invalid security code.");
message.setSeverity(FacesMessage.SEVERITY_INFO);
throw new ValidatorException(message);
}
}
You can retrieve the request object from the JSF External Context, which is accessible from the FacesContext, using the following code:
HttpServletRequest request = (HttpServletRequest) FacesContext.getCurrentInstance().getExternalContext().getRequest();
Edit (thanks to McDowell) :
Another way is to use the FacesContext.getCurrentInstance().getExternalContext().getRequestParameterMap() method to access the request parameters...