gumil / Cities

Directory of cities

Cities

Shows a list of 200k cities and its location in the map from a json file

Source Link

https://github.com/gumil/Cities

Solution

Steps:

1. Read cities.json by line
2. If line is valid, parse to line using Gson
3. Add City into TreeMap using city name and country as key

Since the json file is formatted where each line can be parsed to a city, the list of cities is processed by getting every line since it's safer to process the cities.json file that way. Reading in by buffer might cause OutOfMemoryError. Also reading by chunks can result to malformed json and might need to combine from different chunks.

Using TreeMap, it can eliminate duplicates and sort the map when inserting. Searching is also easier since it can get a submap based on prefix.