Reading error when I click firstfaces download a second time

Question

Hi, I implemented the example shown in the hatch showcase for FileDownload

When I process the page and when I first click the download button, I can upload the file. But when you click on download, then the second time it gives me the following exception.

javax.faces.FacesException: java.io.IOException: Read error at org.apache.myfaces.shared_impl.context.ExceptionHandlerImpl.wrap(ExceptionHandlerImpl.java:241) at org.apache.myfaces.shared_impl.context.ExceptionHandlerImpl.handle(ExceptionHandlerImpl.java:156) at org.apache.myfaces.lifecycle.LifecycleImpl.executePhase(LifecycleImpl.java:191) at org.apache.myfaces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118) at javax.faces.webapp.FacesServlet.service(FacesServlet.java:189) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.apache.myfaces.webapp.filter.ExtensionsFilter.doFilter(ExtensionsFilter.java:147) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:224) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:928) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:987) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:539) at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:1815) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:662) Caused by: java.io.IOException: Read error at java.io.FileInputStream.readBytes(Native Method) at java.io.FileInputStream.read(FileInputStream.java:198) at org.primefaces.component.filedownload.FileDownloadActionListener.processAction(FileDownloadActionListener.java:71) at javax.faces.event.ActionEvent.processListener(ActionEvent.java:51) at javax.faces.component.UIComponentBase.broadcast(UIComponentBase.java:344) at javax.faces.component.UICommand.broadcast(UICommand.java:103) at javax.faces.component.UIViewRoot._broadcastAll(UIViewRoot.java:978) at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:275) at javax.faces.component.UIViewRoot._process(UIViewRoot.java:1289) at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:716) at org.apache.myfaces.lifecycle.InvokeApplicationExecutor.execute(InvokeApplicationExecutor.java:34) at org.apache.myfaces.lifecycle.LifecycleImpl.executePhase(LifecycleImpl.java:171) ... 21 more. 

I insert my code here FileDownloadController.java

 @ManagedBean(name="fileDownloadController") @SessionScoped public class FileDownloadController { private StreamedContent file; public FileDownloadController() { File fileabc=new File("C:/temp/velocitypdf.pdf"); InputStream stream=null; try { stream = new FileInputStream(fileabc); file = new DefaultStreamedContent(stream, "application/pdf", "velocity.pdf"); stream.close(); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } public StreamedContent getFile() { return this. file; } } 

My xhtml file

 <h:form> <p:dialog modal="true" widgetVar="statusDialog" header="Status" draggable="false" closable="false" resizable="false"> </p:dialog> </h:form> <h:form id="form"> <h:commandLink value="Download" onclick="PrimeFaces.monitorDownload(showStatus, hideStatus)"> <p:fileDownload value="#{fileDownloadController.file}" /> </h:commandLink> </h:form> 

1) How can I make it work and what kind of problem.

2) I have files on one of our shared drives, so when I get a stream from getResourceasStream, I get an empty stream. For this, I directly use FileInputStream to read the file. Is this the correct method?

3) If I have 3 files to upload, do I need to write 3 <p:fileDownload> tags?

Answer 1

line 16 looks through line 16 from the demo

 InputStream stream = ((ServletContext)FacesContext.getCurrentInstance().getExternalContext().getContext()). getResourceAsStream("/images/optimusprime.jpg"); 

You need to access the resource using jsf.

 (ServletContext)FacesContext.getCurrentInstance().getExternalContext().getContext("your path in project") 

Since in Java EE you do not have permission to access the file directly from the root path.

Answer 2

You need to create another method, and then copy the code and paste the new method into the constructor.

In the download button to call a new method with an action attribute

sorry for my English

Answer 3

if you copy it null, you should get the file or upload. here is an example:

 private UploadedFile file; private StreamedContent archivoDescargar; //method get public StreamedContent getArchivoDescargar() throws IOException { if(file != null) return archivoDescargar = new DefaultStreamedContent(this.file.getInputstream(),this.file.getContentType(), this.file.getFileName()); else return archivoDescargar; }