code: /*
   * 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.skywalking.library.elasticsearch.requests.search;
  
  import com.google.common.collect.ImmutableList;
  
  import static com.google.common.collect.ImmutableList.toImmutableList;
  import static java.util.Objects.requireNonNull;
  
  public final class BoolQueryBuilder implements QueryBuilder {
      private ImmutableList.Builder<QueryBuilder> must;
      private ImmutableList.Builder<QueryBuilder> mustNot;
      private ImmutableList.Builder<QueryBuilder> should;
      private ImmutableList.Builder<QueryBuilder> shouldNot;
  
      BoolQueryBuilder() {
      }
  
      public BoolQueryBuilder must(QueryBuilder queryBuilder) {
          requireNonNull(queryBuilder, "queryBuilder");
          must().add(queryBuilder);
          return this;
      }
  
      public BoolQueryBuilder mustNot(QueryBuilder queryBuilder) {
          requireNonNull(queryBuilder, "queryBuilder");
          mustNot().add(queryBuilder);
          return this;
      }
  
      public BoolQueryBuilder should(QueryBuilder queryBuilder) {
          requireNonNull(queryBuilder, "queryBuilder");
          should().add(queryBuilder);
          return this;
      }
  
      public BoolQueryBuilder shouldNot(QueryBuilder queryBuilder) {
          requireNonNull(queryBuilder, "queryBuilder");
          shouldNot().add(queryBuilder);
          return this;
      }
  
      private ImmutableList.Builder<QueryBuilder> must() {
          if (must == null) {
              must = ImmutableList.builder();
          }
          return must;
      }
  
      private ImmutableList.Builder<QueryBuilder> mustNot() {
          if (mustNot == null) {
              mustNot = ImmutableList.builder();
          }
          return mustNot;
      }
  
      private ImmutableList.Builder<QueryBuilder> should() {
          if (should == null) {
              should = ImmutableList.builder();
          }
          return should;
      }
  
      private ImmutableList.Builder<QueryBuilder> shouldNot() {
          if (shouldNot == null) {
              shouldNot = ImmutableList.builder();
          }
          return shouldNot;
      }
  
      @Override
      public Query build() {
          final ImmutableList<Query> must;
          if (this.must == null) {
              must = null;
          } else {
              must = this.must.build().stream()
                              .map(QueryBuilder::build)
                              .collect(toImmutableList());
          }
          final ImmutableList<Query> should;
          if (this.should == null) {
              should = null;
          } else {
              should = this.should.build().stream()
                                  .map(QueryBuilder::build)
                                  .collect(toImmutableList());
          }
          final ImmutableList<Query> mustNot;
          if (this.mustNot == null) {
              mustNot = null;
          } else {
              mustNot = this.mustNot.build().stream()
                                    .map(QueryBuilder::build)
                                    .collect(toImmutableList());
          }
          final ImmutableList<Query> shouldNot;
          if (this.shouldNot == null) {
              shouldNot = null;
          } else {
              shouldNot = this.shouldNot.build().stream()
                                        .map(QueryBuilder::build)
                                        .collect(toImmutableList());
          }
          return new BoolQuery(must, mustNot, should, shouldNot);
      }
  }
  