geode-core/src/main/java/org/apache/geode/cache/query/types/CollectionType.java

/*
 * 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.geode.cache.query.types;

/**
 * Represents the type of a collection, an object that can contain element objects.
 *
 * @since GemFire 4.0
 */
public interface CollectionType extends ObjectType {

  /**
   * Return the type of the elements of this collection type.
   */
  ObjectType getElementType();

  /**
   * Return whether duplicates are kept in this type of collection. Duplicates are two objects are
   * equal to each other as defined by the <code>equals</code> method.
   *
   * @return true if duplicates have been retained, false if duplicates have been eliminated
   */
  boolean allowsDuplicates();

  /**
   * Return whether this collection type has ordered elements.
   *
   * @return true if this collection type is ordered, false if not
   */
  boolean isOrdered();
}