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ImmutableEmptyStack.java
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ImmutableEmptyStack.java
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/*
* Copyright (c) 2019 Goldman Sachs and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* and Eclipse Distribution License v. 1.0 which accompany this distribution.
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*/
package org.eclipse.collections.impl.stack.immutable;
import java.io.Serializable;
import java.util.Collection;
import java.util.Comparator;
import java.util.EmptyStackException;
import java.util.Iterator;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Optional;
import org.eclipse.collections.api.BooleanIterable;
import org.eclipse.collections.api.ByteIterable;
import org.eclipse.collections.api.CharIterable;
import org.eclipse.collections.api.DoubleIterable;
import org.eclipse.collections.api.FloatIterable;
import org.eclipse.collections.api.IntIterable;
import org.eclipse.collections.api.LongIterable;
import org.eclipse.collections.api.RichIterable;
import org.eclipse.collections.api.ShortIterable;
import org.eclipse.collections.api.bag.ImmutableBag;
import org.eclipse.collections.api.block.function.Function;
import org.eclipse.collections.api.block.function.Function0;
import org.eclipse.collections.api.block.function.Function2;
import org.eclipse.collections.api.block.function.primitive.BooleanFunction;
import org.eclipse.collections.api.block.function.primitive.ByteFunction;
import org.eclipse.collections.api.block.function.primitive.CharFunction;
import org.eclipse.collections.api.block.function.primitive.DoubleFunction;
import org.eclipse.collections.api.block.function.primitive.FloatFunction;
import org.eclipse.collections.api.block.function.primitive.IntFunction;
import org.eclipse.collections.api.block.function.primitive.LongFunction;
import org.eclipse.collections.api.block.function.primitive.ShortFunction;
import org.eclipse.collections.api.block.predicate.Predicate;
import org.eclipse.collections.api.block.predicate.Predicate2;
import org.eclipse.collections.api.block.procedure.Procedure;
import org.eclipse.collections.api.block.procedure.Procedure2;
import org.eclipse.collections.api.block.procedure.primitive.ObjectIntProcedure;
import org.eclipse.collections.api.collection.primitive.MutableBooleanCollection;
import org.eclipse.collections.api.collection.primitive.MutableByteCollection;
import org.eclipse.collections.api.collection.primitive.MutableCharCollection;
import org.eclipse.collections.api.collection.primitive.MutableDoubleCollection;
import org.eclipse.collections.api.collection.primitive.MutableFloatCollection;
import org.eclipse.collections.api.collection.primitive.MutableIntCollection;
import org.eclipse.collections.api.collection.primitive.MutableLongCollection;
import org.eclipse.collections.api.collection.primitive.MutableShortCollection;
import org.eclipse.collections.api.list.ListIterable;
import org.eclipse.collections.api.map.ImmutableMap;
import org.eclipse.collections.api.map.MutableMapIterable;
import org.eclipse.collections.api.map.primitive.ImmutableObjectDoubleMap;
import org.eclipse.collections.api.map.primitive.ImmutableObjectLongMap;
import org.eclipse.collections.api.multimap.MutableMultimap;
import org.eclipse.collections.api.multimap.list.ImmutableListMultimap;
import org.eclipse.collections.api.ordered.OrderedIterable;
import org.eclipse.collections.api.partition.list.PartitionImmutableList;
import org.eclipse.collections.api.partition.stack.PartitionImmutableStack;
import org.eclipse.collections.api.stack.ImmutableStack;
import org.eclipse.collections.api.stack.MutableStack;
import org.eclipse.collections.api.stack.StackIterable;
import org.eclipse.collections.api.stack.primitive.ImmutableBooleanStack;
import org.eclipse.collections.api.stack.primitive.ImmutableByteStack;
import org.eclipse.collections.api.stack.primitive.ImmutableCharStack;
import org.eclipse.collections.api.stack.primitive.ImmutableDoubleStack;
import org.eclipse.collections.api.stack.primitive.ImmutableFloatStack;
import org.eclipse.collections.api.stack.primitive.ImmutableIntStack;
import org.eclipse.collections.api.stack.primitive.ImmutableLongStack;
import org.eclipse.collections.api.stack.primitive.ImmutableShortStack;
import org.eclipse.collections.api.tuple.Pair;
import org.eclipse.collections.impl.AbstractRichIterable;
import org.eclipse.collections.impl.EmptyIterator;
import org.eclipse.collections.impl.factory.Bags;
import org.eclipse.collections.impl.factory.Lists;
import org.eclipse.collections.impl.factory.Maps;
import org.eclipse.collections.impl.factory.Multimaps;
import org.eclipse.collections.impl.factory.Stacks;
import org.eclipse.collections.impl.factory.primitive.BooleanStacks;
import org.eclipse.collections.impl.factory.primitive.ByteStacks;
import org.eclipse.collections.impl.factory.primitive.CharStacks;
import org.eclipse.collections.impl.factory.primitive.DoubleStacks;
import org.eclipse.collections.impl.factory.primitive.FloatStacks;
import org.eclipse.collections.impl.factory.primitive.IntStacks;
import org.eclipse.collections.impl.factory.primitive.LongStacks;
import org.eclipse.collections.impl.factory.primitive.ObjectDoubleMaps;
import org.eclipse.collections.impl.factory.primitive.ObjectLongMaps;
import org.eclipse.collections.impl.factory.primitive.ShortStacks;
import org.eclipse.collections.impl.partition.list.PartitionFastList;
final class ImmutableEmptyStack<T>
extends AbstractRichIterable<T>
implements ImmutableStack<T>, Serializable
{
static final ImmutableStack<?> INSTANCE = new ImmutableEmptyStack<>();
private static final PartitionImmutableList<?> EMPTY = new PartitionFastList<>().toImmutable();
private static final long serialVersionUID = 1L;
private Object readResolve()
{
return INSTANCE;
}
@Override
public ImmutableStack<T> push(T item)
{
return new ImmutableNotEmptyStack<>(item, this);
}
@Override
public ImmutableStack<T> pop()
{
throw new EmptyStackException();
}
@Override
public ImmutableStack<T> pop(int count)
{
this.checkNegativeCount(count);
if (this.checkZeroCount(count))
{
return this;
}
throw new EmptyStackException();
}
@Override
public T peek()
{
throw new EmptyStackException();
}
@Override
public ListIterable<T> peek(int count)
{
this.checkNegativeCount(count);
if (this.checkZeroCount(count))
{
return Lists.mutable.empty();
}
throw new EmptyStackException();
}
private boolean checkZeroCount(int count)
{
return count == 0;
}
private void checkNegativeCount(int count)
{
if (count < 0)
{
throw new IllegalArgumentException("Count must be positive but was " + count);
}
}
@Override
public T peekAt(int index)
{
this.checkNegativeCount(index);
throw new EmptyStackException();
}
@Override
public T getFirst()
{
throw new EmptyStackException();
}
@Override
public T getLast()
{
throw new UnsupportedOperationException("Cannot call getLast() on " + this.getClass().getSimpleName());
}
@Override
public MutableStack<T> toStack()
{
return Stacks.mutable.empty();
}
@Override
public ImmutableStack<T> select(Predicate<? super T> predicate)
{
return this;
}
@Override
public <P> ImmutableStack<T> selectWith(Predicate2<? super T, ? super P> predicate, P parameter)
{
return this;
}
@Override
public <R extends Collection<T>> R select(Predicate<? super T> predicate, R target)
{
return target;
}
@Override
public <P, R extends Collection<T>> R selectWith(Predicate2<? super T, ? super P> predicate, P parameter, R target)
{
return target;
}
@Override
public ImmutableStack<T> reject(Predicate<? super T> predicate)
{
return this;
}
@Override
public <R extends Collection<T>> R reject(Predicate<? super T> predicate, R target)
{
return target;
}
@Override
public <P> ImmutableStack<T> rejectWith(Predicate2<? super T, ? super P> predicate, P parameter)
{
return this;
}
@Override
public <P, R extends Collection<T>> R rejectWith(Predicate2<? super T, ? super P> predicate, P parameter, R target)
{
return target;
}
@Override
public PartitionImmutableStack<T> partition(Predicate<? super T> predicate)
{
return (PartitionImmutableStack<T>) EMPTY;
}
@Override
public <P> PartitionImmutableStack<T> partitionWith(Predicate2<? super T, ? super P> predicate, P parameter)
{
return (PartitionImmutableStack<T>) EMPTY;
}
@Override
public <S> ImmutableStack<S> selectInstancesOf(Class<S> clazz)
{
return Stacks.immutable.empty();
}
@Override
public <V> ImmutableStack<V> collect(Function<? super T, ? extends V> function)
{
return Stacks.immutable.empty();
}
@Override
public ImmutableBooleanStack collectBoolean(BooleanFunction<? super T> booleanFunction)
{
return BooleanStacks.immutable.empty();
}
@Override
public <R extends MutableBooleanCollection> R collectBoolean(BooleanFunction<? super T> booleanFunction, R target)
{
return target;
}
@Override
public <R extends MutableBooleanCollection> R flatCollectBoolean(
Function<? super T, ? extends BooleanIterable> function, R target)
{
return target;
}
@Override
public ImmutableByteStack collectByte(ByteFunction<? super T> byteFunction)
{
return ByteStacks.immutable.empty();
}
@Override
public <R extends MutableByteCollection> R collectByte(ByteFunction<? super T> byteFunction, R target)
{
return target;
}
@Override
public <R extends MutableByteCollection> R flatCollectByte(
Function<? super T, ? extends ByteIterable> function, R target)
{
return target;
}
@Override
public ImmutableCharStack collectChar(CharFunction<? super T> charFunction)
{
return CharStacks.immutable.empty();
}
@Override
public <R extends MutableCharCollection> R collectChar(CharFunction<? super T> charFunction, R target)
{
return target;
}
@Override
public <R extends MutableCharCollection> R flatCollectChar(
Function<? super T, ? extends CharIterable> function, R target)
{
return target;
}
@Override
public ImmutableDoubleStack collectDouble(DoubleFunction<? super T> doubleFunction)
{
return DoubleStacks.immutable.empty();
}
@Override
public <R extends MutableDoubleCollection> R collectDouble(DoubleFunction<? super T> doubleFunction, R target)
{
return target;
}
@Override
public <R extends MutableDoubleCollection> R flatCollectDouble(
Function<? super T, ? extends DoubleIterable> function, R target)
{
return target;
}
@Override
public ImmutableFloatStack collectFloat(FloatFunction<? super T> floatFunction)
{
return FloatStacks.immutable.empty();
}
@Override
public <R extends MutableFloatCollection> R collectFloat(FloatFunction<? super T> floatFunction, R target)
{
return target;
}
@Override
public <R extends MutableFloatCollection> R flatCollectFloat(
Function<? super T, ? extends FloatIterable> function, R target)
{
return target;
}
@Override
public ImmutableIntStack collectInt(IntFunction<? super T> intFunction)
{
return IntStacks.immutable.empty();
}
@Override
public <R extends MutableIntCollection> R collectInt(IntFunction<? super T> intFunction, R target)
{
return target;
}
@Override
public <R extends MutableIntCollection> R flatCollectInt(
Function<? super T, ? extends IntIterable> function, R target)
{
return target;
}
@Override
public ImmutableLongStack collectLong(LongFunction<? super T> longFunction)
{
return LongStacks.immutable.empty();
}
@Override
public <R extends MutableLongCollection> R collectLong(LongFunction<? super T> longFunction, R target)
{
return target;
}
@Override
public <R extends MutableLongCollection> R flatCollectLong(
Function<? super T, ? extends LongIterable> function, R target)
{
return target;
}
@Override
public ImmutableShortStack collectShort(ShortFunction<? super T> shortFunction)
{
return ShortStacks.immutable.empty();
}
@Override
public <R extends MutableShortCollection> R collectShort(ShortFunction<? super T> shortFunction, R target)
{
return target;
}
@Override
public <R extends MutableShortCollection> R flatCollectShort(
Function<? super T, ? extends ShortIterable> function, R target)
{
return target;
}
@Override
public <V, R extends Collection<V>> R collect(Function<? super T, ? extends V> function, R target)
{
return target;
}
@Override
public <P, V> ImmutableStack<V> collectWith(Function2<? super T, ? super P, ? extends V> function, P parameter)
{
return Stacks.immutable.empty();
}
@Override
public <P, V, R extends Collection<V>> R collectWith(Function2<? super T, ? super P, ? extends V> function, P parameter, R target)
{
return target;
}
@Override
public <V> ImmutableStack<V> collectIf(Predicate<? super T> predicate, Function<? super T, ? extends V> function)
{
return Stacks.immutable.empty();
}
@Override
public <V, R extends Collection<V>> R collectIf(Predicate<? super T> predicate, Function<? super T, ? extends V> function, R target)
{
return target;
}
@Override
public <V> ImmutableStack<V> flatCollect(Function<? super T, ? extends Iterable<V>> function)
{
return Stacks.immutable.empty();
}
@Override
public <V, R extends Collection<V>> R flatCollect(Function<? super T, ? extends Iterable<V>> function, R target)
{
return target;
}
@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 Optional<T> detectOptional(Predicate<? super T> predicate)
{
return Optional.empty();
}
@Override
public <P> Optional<T> detectWithOptional(Predicate2<? super T, ? super P> predicate, P parameter)
{
return Optional.empty();
}
@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 <R extends Collection<T>> R into(R target)
{
return target;
}
@Override
public <NK, NV, R extends Map<NK, NV>> R toMap(Function<? super T, ? extends NK> keyFunction, Function<? super T, ? extends NV> valueFunction, R target)
{
return target;
}
@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 <V> ImmutableObjectLongMap<V> sumByInt(Function<? super T, ? extends V> groupBy, IntFunction<? super T> function)
{
return ObjectLongMaps.immutable.empty();
}
@Override
public <V> ImmutableObjectDoubleMap<V> sumByFloat(Function<? super T, ? extends V> groupBy, FloatFunction<? super T> function)
{
return ObjectDoubleMaps.immutable.empty();
}
@Override
public <V> ImmutableObjectLongMap<V> sumByLong(Function<? super T, ? extends V> groupBy, LongFunction<? super T> function)
{
return ObjectLongMaps.immutable.empty();
}
@Override
public <V> ImmutableObjectDoubleMap<V> sumByDouble(Function<? super T, ? extends V> groupBy, DoubleFunction<? super T> function)
{
return ObjectDoubleMaps.immutable.empty();
}
@Override
public <V> ImmutableListMultimap<V, T> groupBy(Function<? super T, ? extends V> function)
{
return Multimaps.immutable.list.empty();
}
@Override
public <V, R extends MutableMultimap<V, T>> R groupBy(Function<? super T, ? extends V> function, R target)
{
return target;
}
@Override
public <V> ImmutableListMultimap<V, T> groupByEach(Function<? super T, ? extends Iterable<V>> function)
{
return Multimaps.immutable.list.empty();
}
@Override
public <V, R extends MutableMultimap<V, T>> R groupByEach(Function<? super T, ? extends Iterable<V>> function, R target)
{
return target;
}
@Override
public <V> ImmutableMap<V, T> groupByUniqueKey(Function<? super T, ? extends V> function)
{
return Maps.immutable.empty();
}
@Override
public <V, R extends MutableMapIterable<V, T>> R groupByUniqueKey(Function<? super T, ? extends V> function, R target)
{
return target;
}
@Override
public <S> ImmutableStack<Pair<T, S>> zip(Iterable<S> that)
{
return Stacks.immutable.empty();
}
@Override
public <S, R extends Collection<Pair<T, S>>> R zip(Iterable<S> that, R target)
{
return target;
}
@Override
public ImmutableStack<Pair<T, Integer>> zipWithIndex()
{
return Stacks.immutable.empty();
}
@Override
public <R extends Collection<Pair<T, Integer>>> R zipWithIndex(R target)
{
return target;
}
@Override
public ImmutableStack<T> toImmutable()
{
return this;
}
@Override
public RichIterable<RichIterable<T>> chunk(int size)
{
if (size <= 0)
{
throw new IllegalArgumentException("Size for groups must be positive but was: " + size);
}
return Lists.immutable.empty();
}
@Override
public <K, V> ImmutableMap<K, V> aggregateInPlaceBy(Function<? super T, ? extends K> groupBy, Function0<? extends V> zeroValueFactory, Procedure2<? super V, ? super T> mutatingAggregator)
{
return Maps.immutable.empty();
}
@Override
public <K, V> ImmutableMap<K, V> aggregateBy(Function<? super T, ? extends K> groupBy, Function0<? extends V> zeroValueFactory, Function2<? super V, ? super T, ? extends V> nonMutatingAggregator)
{
return Maps.immutable.empty();
}
@Override
public <V> ImmutableBag<V> countByEach(Function<? super T, ? extends Iterable<V>> function)
{
return Bags.immutable.empty();
}
@Override
public int size()
{
return 0;
}
@Override
public boolean isEmpty()
{
return true;
}
@Override
public boolean notEmpty()
{
return false;
}
@Override
public ImmutableStack<T> tap(Procedure<? super T> procedure)
{
return this;
}
@Override
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)
{
}
@Override
public ImmutableStack<T> takeWhile(Predicate<? super T> predicate)
{
throw new UnsupportedOperationException(this.getClass().getSimpleName() + ".takeWhile() not implemented yet");
}
@Override
public ImmutableStack<T> dropWhile(Predicate<? super T> predicate)
{
throw new UnsupportedOperationException(this.getClass().getSimpleName() + ".dropWhile() not implemented yet");
}
@Override
public PartitionImmutableStack<T> partitionWhile(Predicate<? super T> predicate)
{
throw new UnsupportedOperationException(this.getClass().getSimpleName() + ".partitionWhile() not implemented yet");
}
@Override
public ImmutableStack<T> distinct()
{
throw new UnsupportedOperationException(this.getClass().getSimpleName() + ".distinct() not implemented yet");
}
@Override
public int indexOf(Object object)
{
throw new UnsupportedOperationException(this.getClass().getSimpleName() + ".indexOf() not implemented yet");
}
@Override
public <S> boolean corresponds(OrderedIterable<S> other, Predicate2<? super T, ? super S> predicate)
{
throw new UnsupportedOperationException(this.getClass().getSimpleName() + ".corresponds() not implemented yet");
}
public boolean hasSameElements(OrderedIterable<T> other)
{
throw new UnsupportedOperationException(this.getClass().getSimpleName() + ".hasSameElements() not implemented yet");
}
@Override
public void forEach(int startIndex, int endIndex, Procedure<? super T> procedure)
{
throw new UnsupportedOperationException(this.getClass().getSimpleName() + ".forEach() not implemented yet");
}
@Override
public void forEachWithIndex(int fromIndex, int toIndex, ObjectIntProcedure<? super T> objectIntProcedure)
{
throw new UnsupportedOperationException(this.getClass().getSimpleName() + ".forEachWithIndex() not implemented yet");
}
@Override
public int detectIndex(Predicate<? super T> predicate)
{
throw new UnsupportedOperationException(this.getClass().getSimpleName() + ".detectIndex() not implemented yet");
}
@Override
public Iterator<T> iterator()
{
return EmptyIterator.getInstance();
}
@Override
public boolean equals(Object o)
{
if (this == o)
{
return true;
}
if (!(o instanceof StackIterable<?>))
{
return false;
}
StackIterable<?> that = (StackIterable<?>) o;
return that.isEmpty();
}
@Override
public int hashCode()
{
return 1;
}
private Object writeReplace()
{
return new ImmutableStackSerializationProxy<>(this);
}
}