1/* 2 * Copyright (C) 2009 The Guava Authors 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except 5 * in compliance with the License. You may obtain a copy of the License at 6 * 7 * http://www.apache.org/licenses/LICENSE-2.0 8 * 9 * Unless required by applicable law or agreed to in writing, software distributed under the 10 * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either 11 * express or implied. See the License for the specific language governing permissions and 12 * limitations under the License. 13 */ 14 15package com.google.common.collect; 16 17import com.google.common.annotations.GwtCompatible; 18import com.google.common.annotations.GwtIncompatible; 19 20import java.util.Comparator; 21 22import javax.annotation.Nullable; 23 24/** 25 * List returned by {@code ImmutableSortedSet.asList()} when the set isn't empty. 26 * 27 * @author Jared Levy 28 * @author Louis Wasserman 29 */ 30@GwtCompatible(emulated = true) 31@SuppressWarnings("serial") 32final class ImmutableSortedAsList<E> extends RegularImmutableAsList<E> 33 implements SortedIterable<E> { 34 ImmutableSortedAsList( 35 ImmutableSortedSet<E> backingSet, ImmutableList<E> backingList) { 36 super(backingSet, backingList); 37 } 38 39 @Override 40 ImmutableSortedSet<E> delegateCollection() { 41 return (ImmutableSortedSet<E>) super.delegateCollection(); 42 } 43 44 @Override public Comparator<? super E> comparator() { 45 return delegateCollection().comparator(); 46 } 47 48 // Override indexOf() and lastIndexOf() to be O(log N) instead of O(N). 49 50 @GwtIncompatible("ImmutableSortedSet.indexOf") 51 // TODO(cpovirk): consider manual binary search under GWT to preserve O(log N) lookup 52 @Override public int indexOf(@Nullable Object target) { 53 int index = delegateCollection().indexOf(target); 54 55 // TODO(kevinb): reconsider if it's really worth making feeble attempts at 56 // sanity for inconsistent comparators. 57 58 // The equals() check is needed when the comparator isn't compatible with 59 // equals(). 60 return (index >= 0 && get(index).equals(target)) ? index : -1; 61 } 62 63 @GwtIncompatible("ImmutableSortedSet.indexOf") 64 @Override public int lastIndexOf(@Nullable Object target) { 65 return indexOf(target); 66 } 67 68 @Override 69 public boolean contains(Object target) { 70 // Necessary for ISS's with comparators inconsistent with equals. 71 return indexOf(target) >= 0; 72 } 73 74 @GwtIncompatible("super.subListUnchecked does not exist; inherited subList is valid if slow") 75 /* 76 * TODO(cpovirk): if we start to override indexOf/lastIndexOf under GWT, we'll want some way to 77 * override subList to return an ImmutableSortedAsList for better performance. Right now, I'm not 78 * sure there's any performance hit from our failure to override subListUnchecked under GWT 79 */ 80 @Override 81 ImmutableList<E> subListUnchecked(int fromIndex, int toIndex) { 82 return new RegularImmutableSortedSet<E>( 83 super.subListUnchecked(fromIndex, toIndex), comparator()) 84 .asList(); 85 } 86} 87