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.locator;
  
  import java.util.Comparator;
  import java.util.Iterator;
  import java.util.Set;
  import java.util.function.Predicate;
  import java.util.stream.Stream;
  
  import org.apache.cassandra.utils.Sortable;
  
  /**
   * A collection like class for Replica objects. Represents both a well defined order on the contained Replica objects,
   * and efficient methods for accessing the contained Replicas, directly and as a projection onto their endpoints and ranges.
   */
  public interface ReplicaCollection<C extends ReplicaCollection<C>> extends Sortable<Replica, C>
  {
      /**
       * @return a Set of the endpoints of the contained Replicas.
       * Iteration order is maintained where there is a 1:1 relationship between endpoint and Replica
       * Typically this collection offers O(1) access methods, and this is true for all but ReplicaList.
       */
      public abstract Set<InetAddressAndPort> endpoints();
  
      /**
       * @param i a value in the range [0..size())
       * @return the i'th Replica, in our iteration order
       */
      public abstract Replica get(int i);
  
      /**
       * @return the number of Replica contained
       */
      public abstract int size();
  
      /**
       * @return true iff size() == 0
       */
      public abstract boolean isEmpty();
  
      /**
       * @return true iff a Replica in this collection is equal to the provided Replica.
       * Typically this method is expected to take O(1) time, and this is true for all but ReplicaList.
       */
      public abstract boolean contains(Replica replica);
  
      /**
       * @return the number of replicas that match the predicate
       */
      public abstract int count(Predicate<? super Replica> predicate);
  
      /**
       * @return a *eagerly constructed* copy of this collection containing the Replica that match the provided predicate.
       * An effort will be made to either return ourself, or a subList, where possible.
       * It is guaranteed that no changes to any upstream Builder will affect the state of the result.
       */
      public abstract C filter(Predicate<? super Replica> predicate);
  
      /**
       * @return a *eagerly constructed* copy of this collection containing the Replica that match the provided predicate.
       * An effort will be made to either return ourself, or a subList, where possible.
       * It is guaranteed that no changes to any upstream Builder will affect the state of the result.
       * Only the first maxSize items will be returned.
       */
      public abstract C filter(Predicate<? super Replica> predicate, int maxSize);
  
      /**
       * @return a *lazily constructed* Iterable over this collection, containing the Replica that match the provided predicate.
       */
      public abstract Iterable<Replica> filterLazily(Predicate<? super Replica> predicate);
  
      /**
       * @return a *lazily constructed* Iterable over this collection, containing the Replica that match the provided predicate.
       * Only the first maxSize matching items will be returned.
       */
      public abstract Iterable<Replica> filterLazily(Predicate<? super Replica> predicate, int maxSize);
  
      /**
       * @return an *eagerly constructed* copy of this collection containing the Replica at positions [start..end);
       * An effort will be made to either return ourself, or a subList, where possible.
       * It is guaranteed that no changes to any upstream Builder will affect the state of the result.
       */
      public abstract C subList(int start, int end);
  
      /**
       * @return an *eagerly constructed* copy of this collection containing the Replica re-ordered according to this comparator
       * It is guaranteed that no changes to any upstream Builder will affect the state of the result.
       */
      public abstract C sorted(Comparator<? super Replica> comparator);
  
      public abstract Iterator<Replica> iterator();
      public abstract Stream<Replica> stream();
  
      public abstract boolean equals(Object o);
      public abstract int hashCode();
      public abstract String toString();
  
      /**
       * A mutable (append-only) extension of a ReplicaCollection.
       * All methods besides add() will return an immutable snapshot of the collection, or the matching items.
       */
      public interface Builder<C extends ReplicaCollection<C>> extends ReplicaCollection<C>
      {
          /**
           * @return an Immutable clone that assumes this Builder will never be modified again,
           * so its contents can be reused.
           *
           * This Builder should enforce that it is no longer modified.
           */
          public C build();
  
          /**
           * @return an Immutable clone that assumes this Builder will be modified again
           */
          public C snapshot();
  
          /**
           * Passed to add() and addAll() as ignoreConflicts parameter. The meaning of conflict varies by collection type
           * (for Endpoints, it is a duplicate InetAddressAndPort; for RangesAtEndpoint it is a duplicate Range).
           */
          enum Conflict
          {
              /** fail on addition of any such conflict */
              NONE,
              /** fail on addition of any such conflict where the contents differ (first occurrence and position wins) */
              DUPLICATE,
              /** ignore all conflicts (the first occurrence and position wins) */
              ALL
          }
  
          /**
           * @param replica add this replica to the end of the collection
           * @param ignoreConflict conflicts to ignore, see {@link Conflict}
           */
          Builder<C> add(Replica replica, Conflict ignoreConflict);
  
          default public Builder<C> add(Replica replica)
          {
              return add(replica, Conflict.NONE);
          }
  
          default public Builder<C> addAll(Iterable<Replica> replicas, Conflict ignoreConflicts)
          {
              for (Replica replica : replicas)
                  add(replica, ignoreConflicts);
              return this;
          }
  
          default public Builder<C> addAll(Iterable<Replica> replicas)
          {
              return addAll(replicas, Conflict.NONE);
          }
      }
  
  }
  