Use of getResourceAsStream() ??????????

[Shanthi Mari]

I created "site.properties" file in package "com.servlets".

Whenever I run the "index.html" I getting the error displayed as
"Couldn't open /site.properties" from getProperties()ie it couldn't find the resource.But the file is existing there.


package com.servlets;


import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.RequestDispatcher;
import javax.servlet.http.HttpServlet;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.Properties;


//
// Interprets requests from input form
//
public class DispatchDemoServlet extends HttpServlet {
protected ServletConfig _config;
protected ServletContext _ctx;
protected Properties _p;

public DispatchDemoServlet() {
_config = null;
}

// Initialize servlet instance
public void init(ServletConfig config) {
_config = config;

// Load properties from file in war
_ctx = _config.getServletContext();

_p = null;
}

// doGet and doPost do the same thing
public void doGet(HttpServletRequest req, HttpServletResponse res)
throws IOException, ServletException {
doPost(req, res);
}

// Handle post request
public void doPost(HttpServletRequest req, HttpServletResponse res)
throws IOException, ServletException {

String command = req.getParameter("command");

if (command.equals("forward")) {
doForward(req, res);
} else if (command.equals("redirect")) {
doRedirect(req, res);
} else if (command.equals("include")) {
doInclude(req, res);
}
}

// Given a symbolic name of a site, forward to that site
protected void doForward(HttpServletRequest req,
HttpServletResponse res)
throws IOException, ServletException {

String name = req.getParameter("name");

// Look up the site by name
Properties p = getProperties();
String url = (String)p.get(name);
if (url == null) {
url = "errorPage.html";
}

// Get the request dispatcher -- request will be dispatched
// to this URL.

RequestDispatcher rd =
req.getRequestDispatcher(url);

// Forward to requested URL
rd.forward(req, res);
}

// Lazy load of properties
protected Properties getProperties() {
if (_p == null) {
InputStream is = _ctx.getResourceAsStream("/site.properties");

if (is == null) {
System.err.println("Couldn't open /site.properties");
} else {
_p = new Properties();
try {
_p.load(is);
is.close();
} catch (IOException iex) {
System.err.println("Error: " + iex.toString());
}
}
}
return _p;
}
}

[Stefan Evans]

You have a basic misunderstanding of the ServletContext getResourceAsStream method.
It returns resources relative to the WEBSITE ROOT, not to the package/class you are currently in.

Probably you need
_ctx.getResourceAsStream("/WEB-INF/classes/com/servlets/site.properties");

alternatively use the ClassLoader.getResourceAsStream, which searches classpath:
getClassLoader().getResourceAsStream("com/servlets/site.properties");

or load it as a resource bundle:
ResourceBundle rb = ResourceBundle.getBundle("com.servlets.site");

Hope this helps,
evnafets

[Shanthi Mari]

The structure of my Project is:

Servlet
Project
classes
com
servlets
site-properties
public-html
src

I am not having site.properties Under WEB-INF.

can anyone help???

[Ben Souther]

Originally posted by Shanthi Mari:
The structure of my Project is:

Servlet
Project
classes
com
servlets
site-properties
public-html
src


can anyone help???

Either fix the path in getResourceAsStream so that it is relative to your context root or (as Stefan mentioned) read up on ResourceBundles.

[Shanthi Mari]

I tried with ClassLoader, ResourceBundle and getResourceAsStream()
All the three worked .

Thanks for your explanation Stefan.