Error in opening text file in JSF

Question

Hello,
I am developing a Web application using JavaServer Faces Beta Version 1.0 and the Web application needs to open a text file. I used a Java class called by a backingbean class to open the text file.
The problem is that the system cannot find and read the text file.
The system shows the following errors.
Exception report
message
description The server encountered an internal error () that prevented it from fulfilling this request.
exception
javax.servlet.ServletException: javax.faces.el.EvaluationException: java.lang.RuntimeException: Could not
read text file test.txt: java.io.FileNotFoundException: test.txt (The system cannot find the file specified)
     javax.faces.webapp.FacesServlet.service(FacesServlet.java:207)
root cause
javax.faces.FacesException: javax.faces.el.EvaluationException: java.lang.RuntimeException: Could not read
text file test.txt: java.io.FileNotFoundException: test.txt (The system cannot find the file specified)
     com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:83)
     javax.faces.event.ActionEvent.processListener(ActionEvent.java:57)
     javax.faces.component.UIComponentBase.broadcast(UIComponentBase.java:974)
     javax.faces.component.UICommand.broadcast(UICommand.java:274)
     javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:217)
     javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:316)
     com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:80)
     com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:171)
     javax.faces.webapp.FacesServlet.service(FacesServlet.java:196)
note The full stack trace of the root cause is available in the Tomcat logs.
I would like to ask how to open text file in the JSF framework.
Thank you in advance.
regards,
oscar

Answer 1

This is not a JavaServer Faces related issue. Anytime you try to open disk files in a web application, you need to use absolute pathnames. You have no control over what the current directory of our servlet container is set to.
If the file you're reading is actually inside your web application (say, "test.txt" is in a subdirectory "files" ), you can get access to an input stream for it, in a portable way, by calling the getResourceAsStream() method on ServletContext. From an event handler, that might look like this:
  ServletContext sc = (ServletContext) FacesContext.getCurrentInstance().
    getExternalContext().getContext();
  InputStream stream = sc.getResourceAsStream("/files/test.txt");Craig McClanahan