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.asterix.common.annotations;
  
  import java.util.Collection;
  
  public final class IndexedNLJoinExpressionAnnotation extends AbstractExpressionAnnotationWithIndexNames {
  
      public static final String HINT_STRING = "indexnl";
  
      public static final IndexedNLJoinExpressionAnnotation INSTANCE_ANY_INDEX =
              new IndexedNLJoinExpressionAnnotation(null);
  
      private IndexedNLJoinExpressionAnnotation(Collection<String> indexNames) {
          super(indexNames);
      }
  
      public static IndexedNLJoinExpressionAnnotation newInstance(Collection<String> indexNames) {
          if (indexNames == null || indexNames.isEmpty()) {
              throw new IllegalArgumentException();
          }
          return new IndexedNLJoinExpressionAnnotation(indexNames);
      }
  
      public String getHintString() {
          return HINT_STRING;
      }
  
      @Override
      public String toString() {
          return indexNames == null ? HINT_STRING : HINT_STRING + indexNames;
      }
  }
  