Yes, it is possible to find classes of a package in Java. You can Use reflections to find the same.
Below is the code that helps you in determining the classes of a package using reflections.
private Class<?>[] scanForTasks(String packageStr)
{
Reflections reflections = new Reflections((new ConfigurationBuilder()).setScanners(new Scanner[]
{new SubTypesScanner(), new TypeAnnotationsScanner()}).setUrls(ClasspathHelper.forPackage(packageStr, new ClassLoader[0])).filterInputsBy((new FilterBuilder()).includePackage(packageStr)));
Set classes = reflections.getTypesAnnotatedWith(Task.class);
Class[] taskArray = (Class[])classes.toArray(new Class[classes.size()]);
return taskArray;
}
}