@Override
  public MTable ensureGetMTable(String catName, String dbName, String tblName)
      throws NoSuchObjectException {
    MTable mtable = getMTable(catName, dbName, tblName);
    if (mtable == null) {
      throw new NoSuchObjectException("Specified catalog.database.table does not exist : "
          + TableName.getQualified(catName, dbName, tblName));
    }
    return mtable;
  }
Gets the table object for a given table, throws if anything goes wrong.
@param dbName Database name.
@param tblName Table name.
@return Table object.
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/ObjectStore.java