private static MapReduceDriver<Writable, Text, Text, Text, Text, Text> mapReduceDriver;
@BeforeClass
public static void setUpBeforeClass() throws Exception {
Mapper<Writable,Text, Text, Text> mapper = new IdentityJSONMapper();
Reducer<Text,Text,Text,Text> reducer = new JSONReducer();
mapReduceDriver = MapReduceDriver.newMapReduceDriver(mapper, reducer);
filePath = System.getProperty("json.filepath");
}