GsonIO.java

import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

import org.bukkit.craftbukkit.libs.com.google.gson.Gson;
import org.bukkit.craftbukkit.libs.com.google.gson.GsonBuilder;

public class GsonIO {
    public static void createFile(String dir, Object obj){
        File file = new File(dir);
        if (!file.getParentFile().exists()) file.getParentFile().mkdirs();
        try{
            FileWriter writer = null;
            try{
                writer = new FileWriter(file);
                GsonBuilder builder = new GsonBuilder();
                builder.setPrettyPrinting();
                Gson gson = builder.create();
                gson.toJson(obj, writer);
            }
            finally{
                if (writer != null) writer.close();
            }
        }
        catch (IOException e){
            e.printStackTrace();
        }
    }

    public static <T> T getObject(File file, Class<T> type){
        try {
            FileReader reader = null;
            try{
                reader = new FileReader(file);
                if (!file.exists()) return null;
                GsonBuilder builder = new GsonBuilder();
                Gson gson = builder.create();
                return gson.fromJson(reader, type);
            }
            finally{
                if (reader != null) reader.close();
            }
        }
        catch (Exception e){
            e.printStackTrace();
            return null;
        }
    }
}