Cannot load properties file from resources directory

If the file is placed under target/classes after compiling, then it is already in a directory that is part of the build path. The directory src/main/resources is the Maven default directory for such resources, and it is automatically placed to the build path by the Eclipse Maven plugin (M2E). So, there is no need to move your properties file.

The other topic is, how to retrieve such resources. Resources in the build path are automatically in the class path of the running Java program. Considering this, you should always load such resources with a class loader. Example code:

String resourceName = "myconf.properties"; // could also be a constant
ClassLoader loader = Thread.currentThread().getContextClassLoader();
Properties props = new Properties();
try(InputStream resourceStream = loader.getResourceAsStream(resourceName)) {
    props.load(resourceStream);
}
// use props here ...

If it is simple application then getSystemResourceAsStream can also be used.

try (InputStream inputStream = ClassLoader.getSystemResourceAsStream("config.properties"))..

I think you need to put it under src/main/resources and load it as follows:

props.load(new FileInputStream("src/main/resources/myconf.properties"));

The way you are trying to load it will first check in base folder of your project. If it is in target/classes and you want to load it from there do the following:

props.load(new FileInputStream("target/classes/myconf.properties"));