/*
* Copyright (C) 2008 The Guava Authors
*
* Licensed 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 com.google.common.collect;
import static com.google.common.base.Preconditions.checkNotNull;
import com.google.common.annotations.GwtCompatible;
import com.google.common.base.Supplier;
import java.util.Comparator;
import java.util.Map;
import java.util.Set;
import java.util.SortedMap;
import java.util.SortedSet;
/**
* Implementation of {@code Table} whose iteration ordering across row keys is
* sorted by their natural ordering or by a supplied comparator. Note that
* iterations across the columns keys for a single row key may or may not be
* ordered, depending on the implementation. When rows and columns are both
* sorted, it's easier to use the {@link TreeBasedTable} subclass.
*
* <p>The {@link #rowKeySet} method returns a {@link SortedSet} and the {@link
* #rowMap} method returns a {@link SortedMap}, instead of the {@link Set} and
* {@link Map} specified by the {@link Table} interface.
*
* <p>Null keys and values are not supported.
*
* <p>See the {@link StandardTable} superclass for more information about the
* behavior of this class.
*
* @author Jared Levy
*/
@GwtCompatible
class StandardRowSortedTable<R, C, V> extends StandardTable<R, C, V>
implements RowSortedTable<R, C, V> {
/*
* TODO(jlevy): Consider adding headTable, tailTable, and subTable methods,
* which return a Table view with rows keys in a given range. Create a
* RowSortedTable subinterface with the revised methods?
*/
StandardRowSortedTable(SortedMap<R, Map<C, V>> backingMap,
Supplier<? extends Map<C, V>> factory) {
super(backingMap, factory);
}
private SortedMap<R, Map<C, V>> sortedBackingMap() {
return (SortedMap<R, Map<C, V>>) backingMap;
}
private transient SortedSet<R> rowKeySet;
/**
* {@inheritDoc}
*
* <p>This method returns a {@link SortedSet}, instead of the {@code Set}
* specified in the {@link Table} interface.
*/
@Override public SortedSet<R> rowKeySet() {
SortedSet<R> result = rowKeySet;
return (result == null) ? rowKeySet = new RowKeySortedSet() : result;
}
private class RowKeySortedSet extends RowKeySet implements SortedSet<R> {
@Override
public Comparator<? super R> comparator() {
return sortedBackingMap().comparator();
}
@Override
public R first() {
return sortedBackingMap().firstKey();
}
@Override
public R last() {
return sortedBackingMap().lastKey();
}
@Override
public SortedSet<R> headSet(R toElement) {
checkNotNull(toElement);
return new StandardRowSortedTable<R, C, V>(
sortedBackingMap().headMap(toElement), factory).rowKeySet();
}
@Override
public SortedSet<R> subSet(R fromElement, R toElement) {
checkNotNull(fromElement);
checkNotNull(toElement);
return new StandardRowSortedTable<R, C, V>(
sortedBackingMap().subMap(fromElement, toElement), factory)
.rowKeySet();
}
@Override
public SortedSet<R> tailSet(R fromElement) {
checkNotNull(fromElement);
return new StandardRowSortedTable<R, C, V>(
sortedBackingMap().tailMap(fromElement), factory).rowKeySet();
}
}
private transient RowSortedMap rowMap;
/**
* {@inheritDoc}
*
* <p>This method returns a {@link SortedMap}, instead of the {@code Map}
* specified in the {@link Table} interface.
*/
@Override public SortedMap<R, Map<C, V>> rowMap() {
RowSortedMap result = rowMap;
return (result == null) ? rowMap = new RowSortedMap() : result;
}
private class RowSortedMap extends RowMap implements SortedMap<R, Map<C, V>> {
@Override
public Comparator<? super R> comparator() {
return sortedBackingMap().comparator();
}
@Override
public R firstKey() {
return sortedBackingMap().firstKey();
}
@Override
public R lastKey() {
return sortedBackingMap().lastKey();
}
@Override
public SortedMap<R, Map<C, V>> headMap(R toKey) {
checkNotNull(toKey);
return new StandardRowSortedTable<R, C, V>(
sortedBackingMap().headMap(toKey), factory).rowMap();
}
@Override
public SortedMap<R, Map<C, V>> subMap(R fromKey, R toKey) {
checkNotNull(fromKey);
checkNotNull(toKey);
return new StandardRowSortedTable<R, C, V>(
sortedBackingMap().subMap(fromKey, toKey), factory).rowMap();
}
@Override
public SortedMap<R, Map<C, V>> tailMap(R fromKey) {
checkNotNull(fromKey);
return new StandardRowSortedTable<R, C, V>(
sortedBackingMap().tailMap(fromKey), factory).rowMap();
}
}
private static final long serialVersionUID = 0;
}
|