public synchronized static void initialize(final GryoPool gryoPool) {
        GRYO_POOL = gryoPool;
        INITIALIZED = true;
    }
@author Marko A. Rodriguez (http://markorodriguez.com)
hadoop-gremlin/src/main/java/org/apache/tinkerpop/gremlin/hadoop/structure/io/HadoopPools.java