How to load a properties file in J2EE app with Tomcat

Question

I am debugging in Eclipse and Tomcat - and I want to load in a property from a file called foo.properties. The file is stored in src directory, like so:

The following variable is always null:

java.net.URL url = loader.getResource(propFile);

which is becaue (I am guessing) the ClassLoader could locate the foo.properties file.

The properties file only has the text in it:

foo=bar

This is the full code I am using:

private static java.util.Properties prop = new java.util.Properties();
private static void loadProperties() {
// get class loader
ClassLoader loader = Config.class.getClassLoader();
if (loader == null)
 loader = ClassLoader.getSystemClassLoader();

 String propFile = "foo.properties";
 java.net.URL url = loader.getResource(propFile);
 try {
  prop.load(url.openStream()); //ERROR HERE
 } catch (Exception e) {
 System.err.println("Could not load configuration file: " + propFile);
 }
}

This is where I got the code snippet from source code

How do I get this file loaded properly?

Answer 1

Tried using ServletContext#getResourceAsStream(java.lang.String)?

Read http://download.oracle.com/javaee/6/api/javax/servlet/ServletContext.html#getResourceAsStream%28java.lang.String%29 for more details

Answer 2

You might be missing out the package path from your resource name? But that is only a guess.

loader.getResource("com/mypackage/my-properties.properties");

Answer 3

Another way to do it is to learn Spring and use its PropertyPlaceHolderConfigurer

It's overkill for such a simple problem, but you and your app will benefit in lots of other ways.

UPDATE:

The file is stored in src directory

This is the root of your problem.

You need to tell Eclipse how to package your app in such a way that the foo.properties file ends up in the WEB-INF/classes directory of your WAR. Once you figure out how to do that, your app can access the file easily using ServletContext.getResourceAsStream() method.