@Test
public void testConvertDatanodeRegistration() {

  DatanodeID dnId = DFSTestUtil.getLocalDatanodeID();
  BlockKey[] keys = new BlockKey[] { getBlockKey(2), getBlockKey(3) };
  ExportedBlockKeys expKeys = new ExportedBlockKeys(true, 9, 10,
      getBlockKey(1), keys);
  DatanodeRegistration reg = new DatanodeRegistration(dnId,
      new StorageInfo(NodeType.DATA_NODE), expKeys, "3.0.0");
  DatanodeRegistrationProto proto = PBHelper.convert(reg);
  DatanodeRegistration reg2 = PBHelper.convert(proto);
  compare(reg.getStorageInfo(), reg2.getStorageInfo());
  compare(reg.getExportedKeys(), reg2.getExportedKeys());
  compare(reg, reg2);
  assertEquals(reg.getSoftwareVersion(), reg2.getSoftwareVersion());
}