# Returns the `HashSet[JavaString]` value corresponding the given key or `null` if none
	#
	# User has to manage local stack deallocation himself
	#
	# ~~~nitish
	# var a_hash_set = app.shared_preferences.string_set("A key")
	# # ...
	# for element in a_hash_set do element.delete_local_ref
	# ~~~
	fun string_set(key: String): HashSet[JavaString]
	do
		sys.jni_env.push_local_frame(3)
		var return_value = shared_preferences.get_string_set(key.to_java_string)
		sys.jni_env.pop_local_frame
		return return_value
	end