import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;
import org.bukkit.craftbukkit.libs.com.google.gson.JsonElement;
import org.bukkit.craftbukkit.libs.com.google.gson.JsonObject;
import org.bukkit.craftbukkit.libs.com.google.gson.JsonParser;
public class UUIDFetcher {

   private static Map<String, String> uuidCache;

   static {
      uuidCache = new HashMap<String, String>();
   }
   public static String getUUID(String username) {
      if (uuidCache.containsKey(username)) return uuidCache.get(username);
      try {
         URL url = new URL("https://api.mojang.com/users/profiles/minecraft/" + username);
         InputStream stream = url.openStream();
         InputStreamReader inr = new InputStreamReader(stream);
         BufferedReader reader = new BufferedReader(inr);
         String s = null;
         StringBuilder sb = new StringBuilder();
         while ((s = reader.readLine()) != null) {
            sb.append(s);
         }
         String result = sb.toString();

         JsonElement element = new JsonParser().parse(result);
         JsonObject obj = element.getAsJsonObject();

         String uuid = obj.get("id").toString();

         uuid = uuid.substring(1);
         uuid = uuid.substring(0, uuid.length() - 1);

         uuidCache.put(username, uuid);

         return uuid;

      } catch (IOException e) {
         e.printStackTrace();
      }
      return null;
   }
}