[FIXED] Class.getResource() returns null in my Eclipse Application? Can't configure classpath?

Issue

I am trying to use Class.getResource("rsc/my_resource_file.txt") to load a file in an Eclipse application. However, no matter what I do in Eclipse the classpath always contains just one entry to the Eclipse Launcher:

.../eclipse/plugins/org.eclipse.equinox.launcher_1.2.0.v20110502.pkc

How can I configure the classpath?

Note: At runtime I am determining the classpath with the following code:

URLClassLoader cl = (URLClassLoader) ClassLoader.getSystemClassLoader();
for (URL classpathURL : cl.getURLs()) {
    System.out.println(classpathURL);
}

EDIT: Further information.

The root of the problem is that Class.getResource("rsc/my_resource_file.txt") is returning null. Having done some small experiments in a simple 5 line "Java Application" I thought I had figured it out and that the problem was related to the classpath. Apparently the classpath behaves a little different with an "Eclipse Application". I solved the problem by doing Class.getResource("/rsc/my_resource_file.txt") Thanks BalusC.

Solution

Please take a step back. Your concrete problem is that the resource returns null, right? Are you sure that its path is right? As you have, it's relative to the package of the current class. Shouldn't the path start with / to be relative to the package root?

URL resource = getClass().getResource("/rsc/my_resource_file.txt");
// ...

Alternatively, you can also use the context class loader, it's always relative to the classpath (package) root:

ClassLoader loader = Thread.currentThread().getContextClassLoader();
URL resource = loader.getResource("rsc/my_resource_file.txt");
// ...

At least, the Eclipse launcher is not to blame here.

Answered By - BalusC