/*
* Copyright 2015 Goldman Sachs.
*
* 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.gs.collections.impl.bag.immutable;
import java.io.IOException;
import java.io.Serializable;
import java.util.Comparator;
import java.util.Iterator;
import java.util.NoSuchElementException;
import com.gs.collections.api.LazyIterable;
import com.gs.collections.api.RichIterable;
import com.gs.collections.api.bag.Bag;
import com.gs.collections.api.bag.ImmutableBag;
import com.gs.collections.api.bag.MutableBag;
import com.gs.collections.api.bag.primitive.ImmutableBooleanBag;
import com.gs.collections.api.bag.primitive.ImmutableByteBag;
import com.gs.collections.api.bag.primitive.ImmutableCharBag;
import com.gs.collections.api.bag.primitive.ImmutableDoubleBag;
import com.gs.collections.api.bag.primitive.ImmutableFloatBag;
import com.gs.collections.api.bag.primitive.ImmutableIntBag;
import com.gs.collections.api.bag.primitive.ImmutableLongBag;
import com.gs.collections.api.bag.primitive.ImmutableShortBag;
import com.gs.collections.api.bag.sorted.MutableSortedBag;
import com.gs.collections.api.block.function.Function;
import com.gs.collections.api.block.function.Function0;
import com.gs.collections.api.block.function.Function2;
import com.gs.collections.api.block.function.primitive.BooleanFunction;
import com.gs.collections.api.block.function.primitive.ByteFunction;
import com.gs.collections.api.block.function.primitive.CharFunction;
import com.gs.collections.api.block.function.primitive.DoubleFunction;
import com.gs.collections.api.block.function.primitive.FloatFunction;
import com.gs.collections.api.block.function.primitive.IntFunction;
import com.gs.collections.api.block.function.primitive.LongFunction;
import com.gs.collections.api.block.function.primitive.ShortFunction;
import com.gs.collections.api.block.predicate.Predicate;
import com.gs.collections.api.block.predicate.Predicate2;
import com.gs.collections.api.block.predicate.primitive.IntPredicate;
import com.gs.collections.api.block.procedure.Procedure;
import com.gs.collections.api.block.procedure.Procedure2;
import com.gs.collections.api.block.procedure.primitive.ObjectIntProcedure;
import com.gs.collections.api.list.MutableList;
import com.gs.collections.api.map.ImmutableMap;
import com.gs.collections.api.map.MutableMap;
import com.gs.collections.api.map.sorted.MutableSortedMap;
import com.gs.collections.api.multimap.bag.ImmutableBagMultimap;
import com.gs.collections.api.ordered.OrderedIterable;
import com.gs.collections.api.partition.bag.PartitionImmutableBag;
import com.gs.collections.api.set.ImmutableSet;
import com.gs.collections.api.set.MutableSet;
import com.gs.collections.api.tuple.Pair;
import com.gs.collections.impl.EmptyIterator;
import com.gs.collections.impl.bag.mutable.HashBag;
import com.gs.collections.impl.bag.sorted.mutable.TreeBag;
import com.gs.collections.impl.block.factory.Comparators;
import com.gs.collections.impl.factory.Bags;
import com.gs.collections.impl.factory.Lists;
import com.gs.collections.impl.factory.Maps;
import com.gs.collections.impl.factory.Sets;
import com.gs.collections.impl.factory.primitive.BooleanBags;
import com.gs.collections.impl.factory.primitive.ByteBags;
import com.gs.collections.impl.factory.primitive.CharBags;
import com.gs.collections.impl.factory.primitive.DoubleBags;
import com.gs.collections.impl.factory.primitive.FloatBags;
import com.gs.collections.impl.factory.primitive.IntBags;
import com.gs.collections.impl.factory.primitive.LongBags;
import com.gs.collections.impl.factory.primitive.ShortBags;
import com.gs.collections.impl.map.mutable.UnifiedMap;
import com.gs.collections.impl.map.sorted.mutable.TreeSortedMap;
import com.gs.collections.impl.multimap.bag.HashBagMultimap;
import com.gs.collections.impl.partition.bag.PartitionHashBag;
import com.gs.collections.impl.utility.ArrayIterate;
import com.gs.collections.impl.utility.Iterate;
import com.gs.collections.impl.utility.LazyIterate;
import net.jcip.annotations.Immutable;
/**
* This is a zero element {@link ImmutableBag} which is created by calling the Bags.immutable.empty().
*
* @since 1.0
*/
@Immutable
final class ImmutableEmptyBag<T>
extends AbstractImmutableBag<T>
implements Serializable
{
static final ImmutableBag<?> INSTANCE = new ImmutableEmptyBag<Object>();
private static final long serialVersionUID = 1L;
private static final LazyIterable<?> LAZY_ITERABLE = LazyIterate.adapt(INSTANCE);
private static final Object[] TO_ARRAY = new Object[0];
private static final PartitionImmutableBag<Object> IMMUTABLE_EMPTY_PARTITION = new PartitionHashBag<Object>().toImmutable();
@Override
public boolean equals(Object obj)
{
if (obj == this)
{
return true;
}
return obj instanceof Bag && ((Bag<?>) obj).isEmpty();
}
public int sizeDistinct()
{
return 0;
}
public int occurrencesOf(Object item)
{
return 0;
}
public void forEachWithOccurrences(ObjectIntProcedure<? super T> objectIntProcedure)
{
}
public MutableMap<T, Integer> toMapOfItemToCount()
{
return Maps.mutable.empty();
}
@Override
public int hashCode()
{
return 0;
}
public int size()
{
return 0;
}
@Override
public boolean isEmpty()
{
return true;
}
@Override
public boolean notEmpty()
{
return false;
}
@Override
public boolean contains(Object object)
{
return false;
}
@Override
public boolean containsAllIterable(Iterable<?> source)
{
return Iterate.isEmpty(source);
}
@Override
public boolean containsAllArguments(Object... elements)
{
return ArrayIterate.isEmpty(elements);
}
@Override
public ImmutableBag<T> tap(Procedure<? super T> procedure)
{
return this;
}
public void each(Procedure<? super T> procedure)
{
}
@Override
public void forEachWithIndex(ObjectIntProcedure<? super T> objectIntProcedure)
{
}
@Override
public <P> void forEachWith(Procedure2<? super T, ? super P> procedure, P parameter)
{
}
public T getFirst()
{
return null;
}
public T getLast()
{
return null;
}
public Iterator<T> iterator()
{
return EmptyIterator.getInstance();
}
public ImmutableBag<T> newWith(T element)
{
return Bags.immutable.with(element);
}
public ImmutableBag<T> newWithout(T element)
{
return this;
}
public ImmutableBag<T> newWithAll(Iterable<? extends T> elements)
{
return HashBag.newBag(elements).toImmutable();
}
public ImmutableBag<T> selectByOccurrences(IntPredicate predicate)
{
return this;
}
public ImmutableBag<T> select(Predicate<? super T> predicate)
{
return this;
}
@Override
public <P> ImmutableBag<T> selectWith(Predicate2<? super T, ? super P> predicate, P parameter)
{
return this;
}
public ImmutableBag<T> reject(Predicate<? super T> predicate)
{
return this;
}
@Override
public <P> ImmutableBag<T> rejectWith(Predicate2<? super T, ? super P> predicate, P parameter)
{
return this;
}
@Override
public PartitionImmutableBag<T> partition(Predicate<? super T> predicate)
{
return (PartitionImmutableBag<T>) IMMUTABLE_EMPTY_PARTITION;
}
@Override
public <P> PartitionImmutableBag<T> partitionWith(Predicate2<? super T, ? super P> predicate, P parameter)
{
return (PartitionImmutableBag<T>) IMMUTABLE_EMPTY_PARTITION;
}
public <S> ImmutableBag<S> selectInstancesOf(Class<S> clazz)
{
return (ImmutableBag<S>) INSTANCE;
}
public <V> ImmutableBag<V> collect(Function<? super T, ? extends V> function)
{
return (ImmutableBag<V>) INSTANCE;
}
@Override
public ImmutableBooleanBag collectBoolean(BooleanFunction<? super T> booleanFunction)
{
return BooleanBags.immutable.empty();
}
@Override
public ImmutableByteBag collectByte(ByteFunction<? super T> byteFunction)
{
return ByteBags.immutable.empty();
}
@Override
public ImmutableCharBag collectChar(CharFunction<? super T> charFunction)
{
return CharBags.immutable.empty();
}
@Override
public ImmutableDoubleBag collectDouble(DoubleFunction<? super T> doubleFunction)
{
return DoubleBags.immutable.empty();
}
@Override
public ImmutableFloatBag collectFloat(FloatFunction<? super T> floatFunction)
{
return FloatBags.immutable.empty();
}
@Override
public ImmutableIntBag collectInt(IntFunction<? super T> intFunction)
{
return IntBags.immutable.empty();
}
@Override
public ImmutableLongBag collectLong(LongFunction<? super T> longFunction)
{
return LongBags.immutable.empty();
}
@Override
public ImmutableShortBag collectShort(ShortFunction<? super T> shortFunction)
{
return ShortBags.immutable.empty();
}
@Override
public <P, V> ImmutableBag<V> collectWith(Function2<? super T, ? super P, ? extends V> function, P parameter)
{
return (ImmutableBag<V>) INSTANCE;
}
public <V> ImmutableBag<V> collectIf(
Predicate<? super T> predicate,
Function<? super T, ? extends V> function)
{
return (ImmutableBag<V>) INSTANCE;
}
public <V> ImmutableBag<V> flatCollect(Function<? super T, ? extends Iterable<V>> function)
{
return (ImmutableBag<V>) INSTANCE;
}
public <V> ImmutableBagMultimap<V, T> groupBy(Function<? super T, ? extends V> function)
{
// TODO: Create a Singleton ImmutableEmptyBagMultimap for efficiency
return HashBagMultimap.<V, T>newMultimap().toImmutable();
}
public <V> ImmutableBagMultimap<V, T> groupByEach(Function<? super T, ? extends Iterable<V>> function)
{
// TODO: Create a Singleton ImmutableEmptyBagMultimap for efficiency
return HashBagMultimap.<V, T>newMultimap().toImmutable();
}
@Override
public <V> ImmutableMap<V, T> groupByUniqueKey(Function<? super T, ? extends V> function)
{
return Maps.immutable.empty();
}
@Override
public T detect(Predicate<? super T> predicate)
{
return null;
}
@Override
public <P> T detectWith(Predicate2<? super T, ? super P> predicate, P parameter)
{
return null;
}
@Override
public T detectIfNone(Predicate<? super T> predicate, Function0<? extends T> function)
{
return function.value();
}
@Override
public <P> T detectWithIfNone(Predicate2<? super T, ? super P> predicate, P parameter, Function0<? extends T> function)
{
return function.value();
}
@Override
public int count(Predicate<? super T> predicate)
{
return 0;
}
@Override
public <P> int countWith(Predicate2<? super T, ? super P> predicate, P parameter)
{
return 0;
}
@Override
public boolean anySatisfy(Predicate<? super T> predicate)
{
return false;
}
@Override
public boolean allSatisfy(Predicate<? super T> predicate)
{
return true;
}
@Override
public boolean noneSatisfy(Predicate<? super T> predicate)
{
return true;
}
@Override
public <P> boolean anySatisfyWith(Predicate2<? super T, ? super P> predicate, P parameter)
{
return false;
}
@Override
public <P> boolean allSatisfyWith(Predicate2<? super T, ? super P> predicate, P parameter)
{
return true;
}
@Override
public <P> boolean noneSatisfyWith(Predicate2<? super T, ? super P> predicate, P parameter)
{
return true;
}
@Override
public <IV> IV injectInto(IV injectedValue, Function2<? super IV, ? super T, ? extends IV> function)
{
return injectedValue;
}
@Override
public MutableList<T> toList()
{
return Lists.mutable.empty();
}
@Override
public MutableList<T> toSortedList()
{
return Lists.mutable.empty();
}
@Override
public MutableList<T> toSortedList(Comparator<? super T> comparator)
{
return Lists.mutable.empty();
}
@Override
public <V extends Comparable<? super V>> MutableList<T> toSortedListBy(Function<? super T, ? extends V> function)
{
return Lists.mutable.empty();
}
@Override
public MutableSet<T> toSet()
{
return Sets.mutable.empty();
}
@Override
public MutableBag<T> toBag()
{
return Bags.mutable.empty();
}
@Override
public MutableSortedBag<T> toSortedBag()
{
return TreeBag.newBag();
}
@Override
public MutableSortedBag<T> toSortedBag(Comparator<? super T> comparator)
{
return TreeBag.newBag(comparator);
}
@Override
public <V extends Comparable<? super V>> MutableSortedBag<T> toSortedBagBy(Function<? super T, ? extends V> function)
{
return TreeBag.newBag(Comparators.byFunction(function));
}
@Override
public <NK, NV> MutableMap<NK, NV> toMap(
Function<? super T, ? extends NK> keyFunction,
Function<? super T, ? extends NV> valueFunction)
{
return UnifiedMap.newMap();
}
@Override
public <NK, NV> MutableSortedMap<NK, NV> toSortedMap(
Function<? super T, ? extends NK> keyFunction,
Function<? super T, ? extends NV> valueFunction)
{
return TreeSortedMap.newMap();
}
@Override
public <NK, NV> MutableSortedMap<NK, NV> toSortedMap(Comparator<? super NK> comparator,
Function<? super T, ? extends NK> keyFunction,
Function<? super T, ? extends NV> valueFunction)
{
return TreeSortedMap.newMap(comparator);
}
@Override
public LazyIterable<T> asLazy()
{
return (LazyIterable<T>) LAZY_ITERABLE;
}
@Override
public Object[] toArray()
{
return TO_ARRAY;
}
@Override
public <T> T[] toArray(T[] a)
{
if (a.length > 0)
{
a[0] = null;
}
return a;
}
@Override
public T min(Comparator<? super T> comparator)
{
throw new NoSuchElementException();
}
@Override
public T max(Comparator<? super T> comparator)
{
throw new NoSuchElementException();
}
@Override
public T min()
{
throw new NoSuchElementException();
}
@Override
public T max()
{
throw new NoSuchElementException();
}
@Override
public <V extends Comparable<? super V>> T minBy(Function<? super T, ? extends V> function)
{
throw new NoSuchElementException();
}
@Override
public <V extends Comparable<? super V>> T maxBy(Function<? super T, ? extends V> function)
{
throw new NoSuchElementException();
}
@Override
public String toString()
{
return "[]";
}
@Override
public String makeString()
{
return "";
}
@Override
public String makeString(String separator)
{
return "";
}
@Override
public String makeString(String start, String separator, String end)
{
return start + end;
}
@Override
public void appendString(Appendable appendable)
{
}
@Override
public void appendString(Appendable appendable, String separator)
{
}
@Override
public void appendString(Appendable appendable, String start, String separator, String end)
{
try
{
appendable.append(start);
appendable.append(end);
}
catch (IOException e)
{
throw new RuntimeException(e);
}
}
/**
* @deprecated in 6.0. Use {@link OrderedIterable#zip(Iterable)} instead.
*/
@Deprecated
public <S> ImmutableBag<Pair<T, S>> zip(Iterable<S> that)
{
return Bags.immutable.empty();
}
/**
* @deprecated in 6.0. Use {@link OrderedIterable#zipWithIndex()} instead.
*/
@Deprecated
public ImmutableSet<Pair<T, Integer>> zipWithIndex()
{
return Sets.immutable.empty();
}
@Override
public RichIterable<RichIterable<T>> chunk(int size)
{
if (size <= 0)
{
throw new IllegalArgumentException("Size for groups must be positive but was: " + size);
}
return Bags.immutable.empty();
}
private Object writeReplace()
{
return new ImmutableBagSerializationProxy<T>(this);
}
}