Simple JSON Parser APEX

ParseJsonApex.class

public with sharing class parseJson {
	public static void parseJson() {
		String jsonString = '{"Hogwarts":[{"Houses":[{"Hufflepuff":{"members":2}},{"Gryffindor":{"members":4}},{"Slytherin":{"members":3}},{"Ravenclaw":{"members":2}}]},{"Common Areas":{"Inside":"The Great Hall","Outside":"Hagrids Hut"}}]}';
		
		// Load JSON and get to the root of the document
		Map<String, Object> hogwarts = (Map<String,Object>)JSON.deserializeUntyped(jsonString);
		// "Hogwarts" is a List
		List<Object> hogwartsResults = (List<Object>)hogwarts.get('Hogwarts');
		// Houses is the first element in the "Hogwarts" list
		Map<String, Object> houses = (Map<String, Object>)hogwartsResults[0];
		List<Object> houseResults = (List<Object>)houses.get('Houses');
		// "Houses" is a List - let's grab the first one
		Map<String, Object> individualHouse = (Map<String,Object>)houseResults[0];
		//This will print Hufflepuff and it's members
		system.debug('The best house is: ' + individualHouse);
	}	
}