11d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert/* 21d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Copyright (C) 2011 The Guava Authors 37dd252788645e940eada959bdde927426e2531c9Paul Duffin * 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 67dd252788645e940eada959bdde927426e2531c9Paul Duffin * 71d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * http://www.apache.org/licenses/LICENSE-2.0 87dd252788645e940eada959bdde927426e2531c9Paul Duffin * 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 197dd252788645e940eada959bdde927426e2531c9Paul Duffinimport java.util.Collection; 201d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport java.util.Comparator; 211d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 221d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport javax.annotation.Nullable; 231d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 241d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert/** 251d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * An empty immutable sorted multiset. 261d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 271d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * @author Louis Wasserman 281d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 290888a09821a98ac0680fad765217302858e70fa4Paul Duffin@SuppressWarnings("serial") // Uses writeReplace, not default serialization 301d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertfinal class EmptyImmutableSortedMultiset<E> extends ImmutableSortedMultiset<E> { 317dd252788645e940eada959bdde927426e2531c9Paul Duffin private final ImmutableSortedSet<E> elementSet; 327dd252788645e940eada959bdde927426e2531c9Paul Duffin 331d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert EmptyImmutableSortedMultiset(Comparator<? super E> comparator) { 347dd252788645e940eada959bdde927426e2531c9Paul Duffin this.elementSet = ImmutableSortedSet.emptySet(comparator); 351d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 361d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 370888a09821a98ac0680fad765217302858e70fa4Paul Duffin @Override 381d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public Entry<E> firstEntry() { 391d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return null; 401d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 411d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 420888a09821a98ac0680fad765217302858e70fa4Paul Duffin @Override 431d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public Entry<E> lastEntry() { 441d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return null; 451d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 461d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 470888a09821a98ac0680fad765217302858e70fa4Paul Duffin @Override 481d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public int count(@Nullable Object element) { 491d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return 0; 501d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 511d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 521d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 537dd252788645e940eada959bdde927426e2531c9Paul Duffin public boolean containsAll(Collection<?> targets) { 547dd252788645e940eada959bdde927426e2531c9Paul Duffin return targets.isEmpty(); 557dd252788645e940eada959bdde927426e2531c9Paul Duffin } 567dd252788645e940eada959bdde927426e2531c9Paul Duffin 570888a09821a98ac0680fad765217302858e70fa4Paul Duffin @Override 587dd252788645e940eada959bdde927426e2531c9Paul Duffin public int size() { 597dd252788645e940eada959bdde927426e2531c9Paul Duffin return 0; 601d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 611d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 621d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 637dd252788645e940eada959bdde927426e2531c9Paul Duffin public ImmutableSortedSet<E> elementSet() { 647dd252788645e940eada959bdde927426e2531c9Paul Duffin return elementSet; 651d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 661d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 671d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 680888a09821a98ac0680fad765217302858e70fa4Paul Duffin Entry<E> getEntry(int index) { 697dd252788645e940eada959bdde927426e2531c9Paul Duffin throw new AssertionError("should never be called"); 701d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 711d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 721d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 731d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public ImmutableSortedMultiset<E> headMultiset(E upperBound, BoundType boundType) { 741d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert checkNotNull(upperBound); 751d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert checkNotNull(boundType); 761d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return this; 771d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 781d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 791d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 801d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public ImmutableSortedMultiset<E> tailMultiset(E lowerBound, BoundType boundType) { 811d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert checkNotNull(lowerBound); 821d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert checkNotNull(boundType); 831d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return this; 841d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 851d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 861d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 877dd252788645e940eada959bdde927426e2531c9Paul Duffin public UnmodifiableIterator<E> iterator() { 887dd252788645e940eada959bdde927426e2531c9Paul Duffin return Iterators.emptyIterator(); 897dd252788645e940eada959bdde927426e2531c9Paul Duffin } 907dd252788645e940eada959bdde927426e2531c9Paul Duffin 917dd252788645e940eada959bdde927426e2531c9Paul Duffin @Override 927dd252788645e940eada959bdde927426e2531c9Paul Duffin public boolean equals(@Nullable Object object) { 937dd252788645e940eada959bdde927426e2531c9Paul Duffin if (object instanceof Multiset) { 947dd252788645e940eada959bdde927426e2531c9Paul Duffin Multiset<?> other = (Multiset<?>) object; 957dd252788645e940eada959bdde927426e2531c9Paul Duffin return other.isEmpty(); 967dd252788645e940eada959bdde927426e2531c9Paul Duffin } 977dd252788645e940eada959bdde927426e2531c9Paul Duffin return false; 987dd252788645e940eada959bdde927426e2531c9Paul Duffin } 997dd252788645e940eada959bdde927426e2531c9Paul Duffin 1007dd252788645e940eada959bdde927426e2531c9Paul Duffin @Override 1011d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert boolean isPartialView() { 1021d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return false; 1031d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 1047dd252788645e940eada959bdde927426e2531c9Paul Duffin 1057dd252788645e940eada959bdde927426e2531c9Paul Duffin @Override 1060888a09821a98ac0680fad765217302858e70fa4Paul Duffin int copyIntoArray(Object[] dst, int offset) { 1070888a09821a98ac0680fad765217302858e70fa4Paul Duffin return offset; 1087dd252788645e940eada959bdde927426e2531c9Paul Duffin } 1097dd252788645e940eada959bdde927426e2531c9Paul Duffin 1107dd252788645e940eada959bdde927426e2531c9Paul Duffin @Override 1117dd252788645e940eada959bdde927426e2531c9Paul Duffin public ImmutableList<E> asList() { 1127dd252788645e940eada959bdde927426e2531c9Paul Duffin return ImmutableList.of(); 1137dd252788645e940eada959bdde927426e2531c9Paul Duffin } 1141d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert} 115