private static Map<String, Integer> buildLookupTable2(String str){
		if(str==null || !str.contains(" ")) return null;
		char[] s = str.toCharArray();
		StringBuilder sb = new StringBuilder();
		Map<String, Integer> table = new HashMap<>();
		
		for(char c: s){
			
			if(!Character.isWhitespace(c) && Character.isLetter(c)){
				sb.append(c);
			} else {
				String lowerCaseString = sb.toString().toLowerCase();
				
				if(!table.containsKey(lowerCaseString))
					table.put(lowerCaseString, 1);
				else
					table.put(lowerCaseString, table.get(lowerCaseString)+1);	
				
				sb = new StringBuilder();
			}
		}
		
		return table;	
	}