11d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert/* 21d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Copyright (C) 2011 The Guava Authors 31d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 41d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except 51d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * in compliance with the License. You may obtain a copy of the License at 61d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 71d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * http://www.apache.org/licenses/LICENSE-2.0 81d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 91d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Unless required by applicable law or agreed to in writing, software distributed under the License 101d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express 111d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * or implied. See the License for the specific language governing permissions and limitations under 121d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * the License. 131d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 141d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 151d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertpackage com.google.common.collect; 161d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 171d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport static com.google.common.base.Preconditions.checkNotNull; 181d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 191d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport java.util.Comparator; 201d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 211d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport javax.annotation.Nullable; 221d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 231d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert/** 241d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * An empty immutable sorted multiset. 251d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 261d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * @author Louis Wasserman 271d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 281d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertfinal class EmptyImmutableSortedMultiset<E> extends ImmutableSortedMultiset<E> { 291d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert EmptyImmutableSortedMultiset(Comparator<? super E> comparator) { 301d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert super(comparator); 311d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 321d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 331d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 341d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public Entry<E> firstEntry() { 351d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return null; 361d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 371d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 381d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 391d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public Entry<E> lastEntry() { 401d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return null; 411d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 421d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 431d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 441d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public int count(@Nullable Object element) { 451d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return 0; 461d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 471d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 481d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 491d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public int size() { 501d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return 0; 511d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 521d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 531d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 541d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert ImmutableSortedSet<E> createElementSet() { 551d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return ImmutableSortedSet.emptySet(comparator()); 561d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 571d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 581d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 591d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert ImmutableSortedSet<E> createDescendingElementSet() { 601d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return ImmutableSortedSet.emptySet(reverseComparator()); 611d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 621d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 631d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 641d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert UnmodifiableIterator<Entry<E>> descendingEntryIterator() { 651d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return Iterators.emptyIterator(); 661d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 671d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 681d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 691d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert UnmodifiableIterator<Entry<E>> entryIterator() { 701d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return Iterators.emptyIterator(); 711d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 721d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 731d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 741d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public ImmutableSortedMultiset<E> headMultiset(E upperBound, BoundType boundType) { 751d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert checkNotNull(upperBound); 761d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert checkNotNull(boundType); 771d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return this; 781d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 791d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 801d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 811d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public ImmutableSortedMultiset<E> tailMultiset(E lowerBound, BoundType boundType) { 821d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert checkNotNull(lowerBound); 831d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert checkNotNull(boundType); 841d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return this; 851d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 861d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 871d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 881d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert int distinctElements() { 891d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return 0; 901d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 911d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 921d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 931d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert boolean isPartialView() { 941d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return false; 951d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 961d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert} 97