private String calculateImageFilePrefix(){
        StackTraceElement[] stackTrace = Thread.currentThread().getStackTrace();

        // The element at index 2 is the caller of this method, so at 3 should be the test class
        if (stackTrace.length > 3) {
            StackTraceElement caller = stackTrace[3];
            return caller.getClassName() + "." + caller.getMethodName();
        } else {
            throw new RuntimeException("Caller information is not available.");
        }
    }
Sets the file name to be used (as the first part) of saved images in both the resources directory and
the generated image. Note that you only have to call this if you want to override the default behaviour which is
to use the calling class and method name, like org.jmonkeyengine.screenshottests.water.TestPostWater.testPostWater
jme3-screenshot-tests/src/main/java/org/jmonkeyengine/screenshottests/testframework/ScreenshotTest.java