content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package org.apache.cassandra.cql3.ast;
  
  import java.util.stream.Stream;
  
  public interface Element
  {
      void toCQL(StringBuilder sb, CQLFormatter formatter);
  
      default void toCQL(StringBuilder sb)
      {
          toCQL(sb, CQLFormatter.None.instance);
      }
  
      default String toCQL()
      {
          StringBuilder sb = new StringBuilder();
          toCQL(sb, CQLFormatter.None.instance);
          return sb.toString();
      }
  
      default String toCQL(CQLFormatter formatter)
      {
          StringBuilder sb = new StringBuilder();
          toCQL(sb, formatter);
          return sb.toString();
      }
  
      default Stream<? extends Element> stream()
      {
          return Stream.empty();
      }
  
      default Stream<? extends Element> streamRecursive()
      {
          return streamRecursive(false);
      }
  
      default Stream<? extends Element> streamRecursive(boolean includeSelf)
      {
          Stream<Element> stream = stream().flatMap(e -> Stream.concat(Stream.of(e), e.streamRecursive()));
          if (includeSelf)
              stream = Stream.concat(Stream.of(this), stream);
          return stream;
      }
  }
  