private static boolean find(PartitionFieldNode root, Pattern p) {
    if (root == null) {
      return false;
    }
    if (p.matcher(root.fieldName).matches()) {
      return true;
    }
    for (PartitionFieldNode child : root.children) {
      if (find(child, p)) {
        return true;
      }
    }
    return false;
  }
Given a Java regex string pattern, checks if the the partitionFieldNode tree
has any node whose fieldName matches the given pattern
@param searchField
@return
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/PartitionProjectionEvaluator.java