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/*
* Copyright (C) 2002-2022 Sebastiano Vigna
*
* 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 PACKAGE;
import java.util.Spliterator;
import java.util.List;
import static it.unimi.dsi.fastutil.Size64.sizeOf;
#if ! KEYS_USE_REFERENCE_EQUALITY
/** A type-specific {@link List}; provides some additional methods that use polymorphism to avoid (un)boxing.
*
* Note that this type-specific interface extends {@link Comparable}: it is expected that implementing
* classes perform a lexicographical comparison using the standard operator "less then" for primitive types,
* and the usual {@link Comparable#compareTo(Object) compareTo()} method for objects.
*
*
Additionally, this interface strengthens {@link #iterator()}, {@link #listIterator()},
* {@link #listIterator(int)} and {@link #subList(int,int)}. The former had been already
* strengthened upstream, but unfortunately {@link List} re-specifies it.
*
*
Besides polymorphic methods, this interfaces specifies methods to copy into an array or remove contiguous
* sublists. Although the abstract implementation of this interface provides simple, one-by-one implementations
* of these methods, it is expected that concrete implementation override them with optimized versions.
*
* @see List
*/
public interface LIST KEY_GENERIC extends List, Comparable>, COLLECTION KEY_GENERIC {
#else
/** A type-specific {@link List}; provides some additional methods that use polymorphism to avoid (un)boxing.
*
* Additionally, this interface strengthens {@link #iterator()}, {@link #listIterator()},
* {@link #listIterator(int)} and {@link #subList(int,int)}. The former had been already
* strengthened upstream, but unfortunately {@link List} re-specifies it.
*
*
This interface specifies reference equality semantics (members will be compared equal with
* {@code ==} instead of {@link Object#equals(Object) equals}), which may result in breaks in contract
* if attempted to be used with non reference-equality semantics based {@link List}s. For example, a
* {@code aReferenceList.equals(aObjectList)} may return different a different result then
* {@code aObjectList.equals(aReferenceList)}, in violation of {@link Object#equals equals}'s contract
* requiring it being symmetric.
*
*
Besides polymorphic methods, this interfaces specifies methods to copy into an array or remove contiguous
* sublists. Although the abstract implementation of this interface provides simple, one-by-one implementations
* of these methods, it is expected that concrete implementation override them with optimized versions.
*
* @see List
*/
public interface LIST KEY_GENERIC extends List, COLLECTION KEY_GENERIC {
#endif
/** Returns a type-specific iterator on the elements of this list.
*
* @apiNote This specification strengthens the one given in {@link List#iterator()}.
* It would not be normally necessary, but {@link java.lang.Iterable#iterator()} is bizarrily re-specified
* in {@link List}.
* Also, this is generally the only {@code iterator} method subclasses should override.
*
* @return an iterator on the elements of this list.
*/
@Override
KEY_LIST_ITERATOR KEY_GENERIC iterator();
/** Returns a type-specific spliterator on the elements of this list.
*
*
List spliterators must report at least {@link Spliterator#SIZED} and {@link Spliterator#ORDERED}.
*
*
See {@link java.util.List#spliterator()} for more documentation on the requirements
* of the returned spliterator.
*
* @apiNote This specification strengthens the one given in
* {@link java.util.Collection#spliterator()}, which was already
* strengthened in the corresponding type-specific class,
* but was weakened by the fact that this interface extends {@link List}.
*
Also, this is generally the only {@code spliterator} method subclasses should override.
*
* @implSpec The default implementation returns a late-binding spliterator (see
* {@link Spliterator} for documentation on what binding policies mean).
*
* - For {@link java.util.RandomAccess RandomAccess} lists, this will return a spliterator
* that calls the type-specific {@link #get(int)} method on the appropriate indexes.
* - Otherwise, the spliterator returned will wrap this instance's type specific {@link #iterator}.
*
* In either case, the spliterator reports {@link Spliterator#SIZED},
* {@link Spliterator#SUBSIZED}, and {@link Spliterator#ORDERED}.
*
* @implNote As the non-{@linkplain java.util.RandomAccess RandomAccess} case is based on the
* iterator, and {@link java.util.Iterator} is an inherently linear API, the returned
* spliterator will yield limited performance gains when run in parallel contexts, as the
* returned spliterator's {@link Spliterator#trySplit() trySplit()} will have linear runtime.
*
For {@link java.util.RandomAccess RandomAccess} lists, the parallel performance should
* be reasonable assuming {@link #get(int)} is truly constant time like {@link java.util.RandomAccess
* RandomAccess} suggests.
*
* @return {@inheritDoc}
* @since 8.5.0
*/
@Override
#if SPLITERATOR_ASSURE_OVERRIDE
abstract KEY_SPLITERATOR KEY_GENERIC spliterator();
#else
default KEY_SPLITERATOR KEY_GENERIC spliterator() {
if (this instanceof java.util.RandomAccess) {
return new ABSTRACT_LIST.IndexBasedSpliterator KEY_GENERIC_DIAMOND(this, 0);
} else {
return SPLITERATORS.asSpliterator(
iterator(), sizeOf(this), SPLITERATORS.LIST_SPLITERATOR_CHARACTERISTICS);
}
}
#endif
/** Returns a type-specific list iterator on the list.
*
* @see List#listIterator()
*/
@Override
KEY_LIST_ITERATOR KEY_GENERIC listIterator();
/** Returns a type-specific list iterator on the list starting at a given index.
*
* @see List#listIterator(int)
*/
@Override
KEY_LIST_ITERATOR KEY_GENERIC listIterator(int index);
/** Returns a type-specific view of the portion of this list from the index {@code from}, inclusive, to the index {@code to}, exclusive.
*
* @apiNote This specification strengthens the one given in {@link List#subList(int,int)}.
*
* @see List#subList(int,int)
*/
@Override
LIST KEY_GENERIC subList(int from, int to);
/** Sets the size of this list.
*
*
If the specified size is smaller than the current size, the last elements are
* discarded. Otherwise, they are filled with 0/{@code null}/{@code false}.
*
* @param size the new size.
*/
void size(int size);
/** Copies (hopefully quickly) elements of this type-specific list into the given array.
*
* @param from the start index (inclusive).
* @param a the destination array.
* @param offset the offset into the destination array where to store the first element copied.
* @param length the number of elements to be copied.
*/
void getElements(int from, KEY_TYPE a[], int offset, int length);
/** Removes (hopefully quickly) elements of this type-specific list.
*
* @param from the start index (inclusive).
* @param to the end index (exclusive).
*/
void removeElements(int from, int to);
/** Add (hopefully quickly) elements to this type-specific list.
*
* @param index the index at which to add elements.
* @param a the array containing the elements.
*/
void addElements(int index, KEY_GENERIC_TYPE a[]);
/** Add (hopefully quickly) elements to this type-specific list.
*
* @param index the index at which to add elements.
* @param a the array containing the elements.
* @param offset the offset of the first element to add.
* @param length the number of elements to add.
*/
void addElements(int index, KEY_GENERIC_TYPE a[], int offset, int length);
/** Set (hopefully quickly) elements to match the array given.
* @param a the array containing the elements.
* @since 8.3.0
*/
default void setElements(KEY_GENERIC_TYPE a[]) {
setElements(0, a);
}
/** Set (hopefully quickly) elements to match the array given.
* @param index the index at which to start setting elements.
* @param a the array containing the elements.
* @since 8.3.0
*/
default void setElements(int index, KEY_GENERIC_TYPE a[]) {
setElements(index, a, 0, a.length);
}
/** Set (hopefully quickly) elements to match the array given.
*
* Sets each in this list to the corresponding elements in the array, as if by
*
* ListIterator iter = listIterator(index);
* int i = 0;
* while (i < length) {
* iter.next();
* iter.set(a[offset + i++]);
* }
*
* However, the exact implementation may be more efficient, taking into account
* whether random access is faster or not, or at the discretion of subclasses,
* abuse internals.
*
* @param index the index at which to start setting elements.
* @param a the array containing the elements
* @param offset the offset of the first element to add.
* @param length the number of elements to add.
* @since 8.3.0
*/
default void setElements(int index, KEY_GENERIC_TYPE a[], int offset, int length) {
// We can't use AbstractList#ensureIndex, sadly.
if (index < 0) throw new IndexOutOfBoundsException("Index (" + index + ") is negative");
if (index > size()) throw new IndexOutOfBoundsException("Index (" + index + ") is greater than list size (" + (size()) + ")");
ARRAYS.ensureOffsetLength(a, offset, length);
if (index + length > size()) throw new IndexOutOfBoundsException("End index (" + (index + length) + ") is greater than list size (" + size() + ")");
KEY_LIST_ITERATOR KEY_GENERIC iter = listIterator(index);
int i = 0;
while (i < length) {
iter.NEXT_KEY();
iter.set(a[offset + i++]);
}
}
#if KEYS_PRIMITIVE
/** Appends the specified element to the end of this list (optional operation).
* @see List#add(Object)
*/
@Override
boolean add(KEY_TYPE key);
/** Inserts the specified element at the specified position in this list (optional operation).
* @see List#add(int,Object)
*/
void add(int index, KEY_TYPE key);
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead. */
@Deprecated
@Override
default void add(int index, KEY_CLASS key) {
add(index, KEY_CLASS2TYPE(key));
}
/** Inserts all of the elements in the specified type-specific collection into this type-specific list at the specified position (optional operation).
* @see List#addAll(int,java.util.Collection)
*/
boolean addAll(int index, COLLECTION c);
/** Replaces the element at the specified position in this list with the specified element (optional operation).
* @see List#set(int,Object)
*/
KEY_TYPE set(int index, KEY_TYPE k);
/**
* Replaces each element of this list with the result of applying the
* operator to that element.
* @param operator the operator to apply to each element.
* @see java.util.List#replaceAll
*/
default void replaceAll(final METHOD_ARG_KEY_UNARY_OPERATOR operator) {
final KEY_LIST_ITERATOR iter = listIterator();
while(iter.hasNext()) {
iter.set(operator.KEY_OPERATOR_APPLY(iter.NEXT_KEY()));
}
}
#if KEYS_INT_LONG_DOUBLE
// Because our primitive UnaryOperator interface extends both the JDK's primitive
// and object UnaryOperator interfaces, calling this method with it would be ambiguous.
// This overload exists to pass it to the proper primitive overload.
/**
* Replaces each element of this list with the result of applying the
* operator to that element.
*
* WARNING: Overriding this method is almost always a mistake, as this
* overload only exists to disambiguate. Instead, override the {@code replaceAll()} overload
* that uses the JDK's primitive unary operator type (e.g. {@link java.util.function.IntUnaryOperator}).
*
*
If Java supported final default methods, this would be one, but sadly it does not.
*
*
If you checked and are overriding the version with {@code java.util.function.XUnaryOperator}, and
* still see this warning, then your IDE is incorrectly conflating this method with the proper
* method to override, and you can safely ignore this message.
*
* @param operator the operator to apply to each element
* @see java.util.List#replaceAll
* @since 8.5.0
*/
default void replaceAll(final KEY_UNARY_OPERATOR operator) {
replaceAll((METHOD_ARG_KEY_UNARY_OPERATOR) operator);
}
#elif KEYS_BYTE_CHAR_SHORT_FLOAT
/**
* Replaces each element of this list with the result of applying the
* operator to that element, performing widening and narrowing primitive casts,
* until all elements have been processed or the action
* throws an exception.
*
* @param operator the operator to apply to each element
* @see java.util.List#replaceAll
* @since 8.5.0
* @implNote Unless the argument is type-specific, this method will introduce an intermediary
* lambda to perform widening and narrowing casts. Please use the type-specific overload to avoid this overhead.
*/
default void replaceAll(final JDK_PRIMITIVE_UNARY_OPERATOR operator) {
replaceAll(operator instanceof METHOD_ARG_KEY_UNARY_OPERATOR ? (METHOD_ARG_KEY_UNARY_OPERATOR) operator : x -> KEY_NARROWING(operator.JDK_PRIMITIVE_KEY_APPLY(x)));
}
#endif
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead.
*/
@Deprecated
@Override
@SuppressWarnings("boxing")
default void replaceAll(final java.util.function.UnaryOperator operator) {
java.util.Objects.requireNonNull(operator);
// The instanceof and cast is required for performance. Without it, calls routed through this
// overload using a primitive consumer would go through the slow lambda.
replaceAll(operator instanceof METHOD_ARG_KEY_UNARY_OPERATOR ? (METHOD_ARG_KEY_UNARY_OPERATOR) operator : (METHOD_ARG_KEY_UNARY_OPERATOR) operator::apply);
}
/** Returns the element at the specified position in this list.
* @see List#get(int)
*/
KEY_TYPE GET_KEY(int index);
/** Returns the index of the first occurrence of the specified element in this list, or -1 if this list does not contain the element.
* @see List#indexOf(Object)
*/
int indexOf(KEY_TYPE k);
/** Returns the index of the last occurrence of the specified element in this list, or -1 if this list does not contain the element.
* @see List#lastIndexOf(Object)
*/
int lastIndexOf(KEY_TYPE k);
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead.
*/
@Deprecated
@Override
default boolean contains(final Object key) {
return COLLECTION.super.contains(key);
}
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead. */
@Deprecated
@Override
default KEY_GENERIC_CLASS get(int index) {
return KEY2OBJ(GET_KEY(index));
}
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead. */
@Deprecated
@Override
default int indexOf(Object o) {
return indexOf(KEY_OBJ2TYPE(o));
}
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead. */
@Deprecated
@Override
default int lastIndexOf(Object o) {
return lastIndexOf(KEY_OBJ2TYPE(o));
}
/** {@inheritDoc}
* This method specification is a workaround for
* bug 8177440.
* @deprecated Please use the corresponding type-specific method instead. */
@Deprecated
@Override
default boolean add(KEY_CLASS k) {
return add(KEY_CLASS2TYPE(k));
}
/** Removes the element at the specified position in this list (optional operation).
* @see List#remove(int)
*/
KEY_TYPE REMOVE_KEY(int index);
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead.
*/
@Deprecated
@Override
default boolean remove(final Object key) {
return COLLECTION.super.remove(key);
}
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead. */
@Deprecated
@Override
default KEY_GENERIC_CLASS remove(int index) {
return KEY2OBJ(REMOVE_KEY(index));
}
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead. */
@Deprecated
@Override
default KEY_GENERIC_CLASS set(int index, KEY_CLASS k) {
return KEY2OBJ(set(index, KEY_CLASS2TYPE(k)));
}
#endif
/** Inserts all of the elements in the specified type-specific list into this type-specific list at the specified position (optional operation).
* @apiNote This method exists only for the sake of efficiency: override are expected to use {@link #getElements}/{@link #addElements}.
* @implSpec This method delegates to the one accepting a collection, but it might be implemented more efficiently.
* @see List#addAll(int,Collection)
*/
default boolean addAll(int index, LIST KEY_EXTENDS_GENERIC l) {
return addAll(index, (COLLECTION KEY_EXTENDS_GENERIC) l);
}
/** Appends all of the elements in the specified type-specific list to the end of this type-specific list (optional operation).
* @implSpec This method delegates to the index-based version, passing {@link #size()} as first argument.
* @see List#addAll(Collection)
*/
default boolean addAll(LIST KEY_EXTENDS_GENERIC l) {
return addAll(size(), l);
}
/** Returns an immutable empty list.
*
* @return an immutable empty list.
*/
public static KEY_GENERIC LIST KEY_GENERIC of() {
// Returning ImmutableList.EMPTY instead of LISTS.EMPTY_LIST to make dimorphic call site.
// See https://github.com/vigna/fastutil/issues/183
return IMMUTABLE_LIST.of();
}
/** Returns an immutable list with the element given.
*
* @param e the element that the returned list will contain.
* @return an immutable list containing {@code e}.
*/
public static KEY_GENERIC LIST KEY_GENERIC of(final KEY_GENERIC_TYPE e) {
return LISTS.singleton(e);
}
/** Returns an immutable list with the elements given.
*
* @param e0 the first element.
* @param e1 the second element.
* @return an immutable list containing {@code e0} and {@code e1}.
*/
public static KEY_GENERIC LIST KEY_GENERIC of(final KEY_GENERIC_TYPE e0, final KEY_GENERIC_TYPE e1) {
return IMMUTABLE_LIST.of(e0, e1);
}
/** Returns an immutable list with the elements given.
*
* @param e0 the first element.
* @param e1 the second element.
* @param e2 the third element.
* @return an immutable list containing {@code e0}, {@code e1}, and {@code e2}.
*/
public static KEY_GENERIC LIST KEY_GENERIC of(final KEY_GENERIC_TYPE e0, final KEY_GENERIC_TYPE e1, final KEY_GENERIC_TYPE e2) {
return IMMUTABLE_LIST.of(e0, e1, e2);
}
/** Returns an immutable list with the elements given.
*
*
Note that this method does not perform a defensive copy.
*
* @param a a list of elements that will be used to initialize the immutable list.
* @return an immutable list containing the elements of {@code a}.
*/
SUPPRESS_WARNINGS_KEY_UNCHECKED
SAFE_VARARGS
public static KEY_GENERIC LIST KEY_GENERIC of(final KEY_GENERIC_TYPE... a) {
switch(a.length) {
case 0:
return of();
case 1:
return of(a[0]);
// Add cases of 2 and 3 if we ever have special logic for those.
default:
// fall through
}
return IMMUTABLE_LIST.of(a);
}
#if defined(KEY_COMPARATOR) && KEYS_PRIMITIVE
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead.
*/
@Deprecated
@Override
default void sort(final java.util.Comparator comparator) {
sort(COMPARATORS.AS_KEY_COMPARATOR(comparator));
}
/** Sort a list using a type-specific comparator.
*
*
Pass {@code null} to sort using natural ordering.
* @see List#sort(java.util.Comparator)
*
* @implSpec The default implementation dumps the elements into an array using
* {@link #toArray()}, sorts the array, then replaces all elements using the
* {@link #setElements} function.
*
*
It is possible for this method to call {@link #unstableSort} if it can
* determine that the results of a stable and unstable sort are completely equivalent.
* This means if you override {@link #unstableSort}, it should not call this
* method unless you override this method as well.
*
* @since 8.3.0
*/
default void sort(final KEY_COMPARATOR comparator) {
#if !(KEY_CLASS_Float || KEY_CLASS_Double)
if (comparator == null) {
// For non-floating point primitive types, when comparing naturally,
// it is impossible to tell the difference between a stable and not-stable sort.
// So just use the probably faster unstable sort.
unstableSort(comparator);
} else {
KEY_TYPE[] elements = TO_KEY_ARRAY();
ARRAYS.stableSort(elements, comparator);
setElements(elements);
}
#else
KEY_TYPE[] elements = TO_KEY_ARRAY();
if (comparator == null) {
ARRAYS.stableSort(elements);
} else {
ARRAYS.stableSort(elements, comparator);
}
setElements(elements);
#endif
}
/** Sorts this list using a sort not assured to be stable.
* @deprecated Please use the corresponding type-specific method instead.
*/
@Deprecated
default void unstableSort(final java.util.Comparator comparator) {
unstableSort(COMPARATORS.AS_KEY_COMPARATOR(comparator));
}
/** Sorts this list using a sort not assured to be stable.
*
*
Pass {@code null} to sort using natural ordering.
*
*
This differs from {@link List#sort(java.util.Comparator)} in that the results are
* not assured to be stable, but may be a bit faster.
*
*
Unless a subclass specifies otherwise, the results of the method if the list is
* concurrently modified during the sort are unspecified.
*
* @implSpec The default implementation dumps the elements into an array using
* {@link #toArray()}, sorts the array, then replaces all elements using the
* {@link #setElements} function.
*
* @since 8.3.0
*/
default void unstableSort(final KEY_COMPARATOR comparator) {
KEY_TYPE[] elements = TO_KEY_ARRAY();
if (comparator == null) {
ARRAYS.unstableSort(elements);
} else {
ARRAYS.unstableSort(elements, comparator);
}
setElements(elements);
}
#else
#if !KEYS_REFERENCE
#error Assertion error: No KEY_COMPARATOR defined, but not a reference type.
#endif
/** Sorts this list using a sort assured to be stable.
*
*
Pass {@code null} to sort using natural ordering.
*
*
Unless a subclass specifies otherwise, the results of the method if the list is
* concurrently modified during the sort are unspecified.
*
* @implSpec The default implementation dumps the elements into an array using
* {@link #toArray()}, sorts the array, then replaces all elements using the
* {@link #setElements} function.
*
* @since 8.5.0
*/
@Override
SUPPRESS_WARNINGS_KEY_UNCHECKED
default void sort(final java.util.Comparator comparator) {
KEY_GENERIC_TYPE[] elements = (KEY_GENERIC_TYPE[])toArray();
// Current stableSort implementation delegates to java.util.Arrays.sort for reference types,
// so we aren't losing out on JDK's optimized Timsort.
if (comparator == null) {
ARRAYS.stableSort(elements);
} else {
ARRAYS.stableSort(elements, comparator);
}
setElements(elements);
}
/** Sorts this list using a sort not assured to be stable.
* This differs from {@link List#sort(java.util.Comparator)} in that the results are
* not assured to be stable, but may be a bit faster.
*
*
Pass {@code null} to sort using natural ordering.
*
*
Unless a subclass specifies otherwise, the results of the method if the list is
* concurrently modified during the sort are unspecified.
*
* @implSpec The default implementation dumps the elements into an array using
* {@link #toArray()}, sorts the array, then replaces all elements using the
* {@link #setElements} function.
*
* @since 8.3.0
*/
SUPPRESS_WARNINGS_KEY_UNCHECKED
default void unstableSort(final java.util.Comparator comparator) {
KEY_GENERIC_TYPE[] elements = (KEY_GENERIC_TYPE[])toArray();
if (comparator == null) {
ARRAYS.unstableSort(elements);
} else {
ARRAYS.unstableSort(elements, comparator);
}
setElements(elements);
}
#endif
}