public static NamenodeRole convert(NamenodeRoleProto role) {
    switch (role) {
    case NAMENODE:
      return NamenodeRole.NAMENODE;
    case BACKUP:
      return NamenodeRole.BACKUP;
    case CHECKPOINT:
      return NamenodeRole.CHECKPOINT;
    }
    return null;
  }
@Test
  public void testConvertCheckpointSignature() {
    CheckpointSignature s = new CheckpointSignature(
        getStorageInfo(NodeType.NAME_NODE), "bpid", 100, 1);
    CheckpointSignatureProto sProto = PBHelper.convert(s);
    CheckpointSignature s1 = PBHelper.convert(sProto);
    assertEquals(s.getBlockpoolID(), s1.getBlockpoolID());
    assertEquals(s.getClusterID(), s1.getClusterID());
    assertEquals(s.getCTime(), s1.getCTime());
    assertEquals(s.getCurSegmentTxId(), s1.getCurSegmentTxId());
    assertEquals(s.getLayoutVersion(), s1.getLayoutVersion());
    assertEquals(s.getMostRecentCheckpointTxId(),
        s1.getMostRecentCheckpointTxId());
    assertEquals(s.getNamespaceID(), s1.getNamespaceID());
  }