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/*
* Copyright (C) 2002-2015 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 squidpony.squidmath;
import squidpony.annotation.GwtIncompatible;
import java.util.*;
import static squidpony.squidmath.CrossHash.Water.*;
/**
* A generic linked hash set with with a fast implementation, originally from fastutil as ObjectLinkedOpenHashSet but
* modified to support indexed access of items, reordering, and optional hash strategies for array keys (which fastutil
* does differently).
*
* Instances of this class use a hash table to represent a set. The table is
* filled up to a specified load factor, and then doubled in size to
* accommodate new entries. If the table is emptied below one fourth of
* the load factor, it is halved in size. However, halving is not performed when
* deleting entries from an iterator, as it would interfere with the iteration
* process.
*
*
* Note that {@link #clear()} does not modify the hash table size. Rather, a
* family of {@linkplain #trim() trimming methods} lets you control the size of
* the table; this is particularly useful if you reuse instances of this class.
*
*
* Iterators generated by this set will enumerate elements in the same order in
* which they have been added to the set (addition of elements already present
* in the set does not change the iteration order). Note that this order has
* nothing in common with the natural order of the keys. The order is kept by
* means of an array list, represented via an IntVLA parallel to the
* table that can be modified with methods like {@link #shuffle(IRNG)}.
*
*
* This class implements the interface of a sorted set, so to allow easy access
* of the iteration order: for instance, you can get the first element in
* iteration order with {@code first()} without having to create an iterator;
* however, this class partially violates the {@link java.util.SortedSet}
* contract because all subset methods throw an exception and
* {@link #comparator()} returns always null.
*
*
* Additional methods, such as addAndMoveToFirst(), make it easy to
* use instances of this class as a cache (e.g., with LRU policy).
*
*
* This class allows approximately constant-time lookup of keys or values by their index in the ordering, which can
* allow some novel usage of the data structure. OrderedSet can be used like a list of unique elements, keeping order
* like a list does but also allowing rapid checks for whether an item exists in the OrderedSet, and {@link OrderedMap}
* can be used like that but with values associated as well (where OrderedSet uses contains(), OrderedMap uses
* containsKey()). You can also set the item at a position with {@link #addAt(Object, int)}, or alter an item while
* keeping index the same with {@link #alter(Object, Object)}. Reordering works here too, both with completely random
* orders from {@link #shuffle(IRNG)} or with a previously-generated ordering from {@link #reorder(int...)} (you can
* produce such an ordering for a given size and reuse it across multiple Ordered data structures with
* {@link IRNG#randomOrdering(int)}).
*
*
* You can pass an {@link CrossHash.IHasher} instance such as {@link CrossHash#generalHasher} as an extra parameter to
* most of this class' constructors, which allows the OrderedSet to use arrays (usually primitive arrays) as items. If
* you expect only one type of array, you can use an instance like {@link CrossHash#intHasher} to hash int arrays, or
* the aforementioned generalHasher to hash most kinds of arrays (it can't handle most multi-dimensional arrays well).
* If you aren't using array items, you don't need to give an IHasher to the constructor and can ignore this feature.
*
*
* Thank you, Sebastiano Vigna, for making FastUtil available to the public with such high quality.
*
* See https://github.com/vigna/fastutil for the original library.
*
* @author Sebastiano Vigna (responsible for all the hard parts)
* @author Tommy Ettinger (mostly responsible for squashing several layers of parent classes into one monster class)
*/
public class OrderedSet implements SortedSet, java.io.Serializable, Cloneable {
private static final long serialVersionUID = 0L;
/**
* The array of keys.
*/
protected K[] key;
/**
* The array of values.
*/
//protected V[] value;
/**
* The mask for wrapping a position counter.
*/
protected int mask;
/**
* Whether this set contains the key zero.
*/
protected boolean containsNull;
/**
* An IntVLA (variable-length int sequence) that stores the positions in the key array of specific keys, with the
* positions in insertion order. The order can be changed with {@link #reorder(int...)} and other methods.
*/
protected IntVLA order;
/**
* The current table size.
*/
protected int n;
/**
* Threshold after which we rehash. It must be the table size times {@link #f}.
*/
protected int maxFill;
/**
* Number of entries in the set (including the key zero, if present).
*/
protected int size;
/**
* The acceptable load factor.
*/
public final float f;
/**
* The initial default size of a hash table.
*/
public static final int DEFAULT_INITIAL_SIZE = 16;
/**
* The default load factor of a hash table.
*/
public static final float DEFAULT_LOAD_FACTOR = .75f; // .1875f; // .75f;
/**
* The load factor for a (usually small) table that is meant to be particularly fast.
*/
public static final float FAST_LOAD_FACTOR = .5f;
/**
* The load factor for a (usually very small) table that is meant to be extremely fast.
*/
public static final float VERY_FAST_LOAD_FACTOR = .25f;
protected final CrossHash.IHasher hasher;
/**
* Creates a new hash map.
*
*
The actual table size will be the least power of two greater than expected/f.
*
* @param expected the expected number of elements in the hash set.
* @param f the load factor.
*/
@SuppressWarnings("unchecked")
public OrderedSet(final int expected, final float f) {
if (f <= 0 || f > 1)
throw new IllegalArgumentException("Load factor must be greater than 0 and smaller than or equal to 1");
if (expected < 0) throw new IllegalArgumentException("The expected number of elements must be nonnegative");
this.f = f;
n = arraySize(expected, f);
mask = n - 1;
maxFill = maxFill(n, f);
key = (K[]) new Object[n + 1];
//link = new long[n + 1];
order = new IntVLA(expected);
hasher = CrossHash.mildHasher;
}
/**
* Creates a new hash set with {@link #DEFAULT_LOAD_FACTOR} as load
* factor.
*
* @param expected the expected number of elements in the hash set.
*/
public OrderedSet(final int expected) {
this(expected, DEFAULT_LOAD_FACTOR);
}
/**
* Creates a new hash set with initial expected
* {@link #DEFAULT_INITIAL_SIZE} elements and
* {@link #DEFAULT_LOAD_FACTOR} as load factor.
*/
public OrderedSet() {
this(DEFAULT_INITIAL_SIZE, DEFAULT_LOAD_FACTOR);
}
/**
* Creates a new hash set copying a given collection.
*
* @param c a {@link Collection} to be copied into the new hash set.
* @param f the load factor.
*/
public OrderedSet(final Collection c,
final float f) {
this(c.size(), f, (c instanceof OrderedSet) ? ((OrderedSet) c).hasher : CrossHash.mildHasher);
addAll(c);
}
/**
* Creates a new hash set with {@link #DEFAULT_LOAD_FACTOR} as load
* factor copying a given collection.
*
* @param c a {@link Collection} to be copied into the new hash set.
*/
public OrderedSet(final Collection c) {
this(c, (c instanceof OrderedSet) ? ((OrderedSet) c).f : DEFAULT_LOAD_FACTOR, (c instanceof OrderedSet) ? ((OrderedSet) c).hasher : CrossHash.mildHasher);
}
/**
* Creates a new hash set using elements provided by a type-specific
* iterator.
*
* @param i a type-specific iterator whose elements will fill the set.
* @param f the load factor.
*/
public OrderedSet(final Iterator i, final float f) {
this(DEFAULT_INITIAL_SIZE, f);
while (i.hasNext())
add(i.next());
}
/**
* Creates a new hash set with {@link #DEFAULT_LOAD_FACTOR} as load
* factor using elements provided by a type-specific iterator.
*
* @param i a type-specific iterator whose elements will fill the set.
*/
public OrderedSet(final Iterator i) {
this(i, DEFAULT_LOAD_FACTOR);
}
/**
* Creates a new hash set and fills it with the elements of a given array.
*
* @param a an array whose elements will be used to fill the set.
* @param offset the first element to use.
* @param length the number of elements to use.
* @param f the load factor.
*/
public OrderedSet(final K[] a, final int offset,
final int length, final float f) {
this(length < 0 ? 0 : length, f);
if (a == null) throw new NullPointerException("Array passed to OrderedSet constructor cannot be null");
if (offset < 0) throw new ArrayIndexOutOfBoundsException("Offset (" + offset + ") is negative");
if (length < 0) throw new IllegalArgumentException("Length (" + length + ") is negative");
if (offset + length > a.length) {
throw new ArrayIndexOutOfBoundsException(
"Last index (" + (offset + length) + ") is greater than array length (" + a.length + ")");
}
for (int i = 0; i < length; i++)
add(a[offset + i]);
}
/**
* Creates a new hash set with {@link #DEFAULT_LOAD_FACTOR} as load
* factor and fills it with the elements of a given array.
*
* @param a an array whose elements will be used to fill the set.
* @param offset the first element to use.
* @param length the number of elements to use.
*/
public OrderedSet(final K[] a, final int offset,
final int length) {
this(a, offset, length, DEFAULT_LOAD_FACTOR);
}
/**
* Creates a new hash set copying the elements of an array.
*
* @param a an array to be copied into the new hash set.
* @param f the load factor.
*/
public OrderedSet(final K[] a, final float f) {
this(a, 0, a.length, f);
}
/**
* Creates a new hash set with {@link #DEFAULT_LOAD_FACTOR} as load
* factor copying the elements of an array.
*
* @param a an array to be copied into the new hash set.
*/
public OrderedSet(final K[] a) {
this(a, DEFAULT_LOAD_FACTOR);
}
/**
* Creates a new hash map.
*
*
The actual table size will be the least power of two greater than expected/f.
*
* @param expected the expected number of elements in the hash set.
* @param f the load factor.
* @param hasher used to hash items; typically only needed when K is an array, where CrossHash has implementations
*/
@SuppressWarnings("unchecked")
public OrderedSet(final int expected, final float f, CrossHash.IHasher hasher) {
if (f <= 0 || f > 1)
throw new IllegalArgumentException("Load factor must be greater than 0 and smaller than or equal to 1");
if (expected < 0) throw new IllegalArgumentException("The expected number of elements must be nonnegative");
this.f = f;
n = arraySize(expected, f);
mask = n - 1;
maxFill = maxFill(n, f);
key = (K[]) new Object[n + 1];
//link = new long[n + 1];
order = new IntVLA(expected);
this.hasher = hasher == null ? CrossHash.mildHasher : hasher;
}
/**
* Creates a new hash set with {@link #DEFAULT_LOAD_FACTOR} as load
* factor.
*
* @param hasher used to hash items; typically only needed when K is an array, where CrossHash has implementations
*/
public OrderedSet(CrossHash.IHasher hasher) {
this(DEFAULT_INITIAL_SIZE, DEFAULT_LOAD_FACTOR, hasher);
}
/**
* Creates a new hash set with {@link #DEFAULT_LOAD_FACTOR} as load
* factor.
*
* @param hasher used to hash items; typically only needed when K is an array, where CrossHash has implementations
*/
public OrderedSet(final int expected, CrossHash.IHasher hasher) {
this(expected, DEFAULT_LOAD_FACTOR, hasher);
}
/**
* Creates a new hash set copying a given collection.
*
* @param c a {@link Collection} to be copied into the new hash set.
* @param f the load factor.
* @param hasher used to hash items; typically only needed when K is an array, where CrossHash has implementations
*/
public OrderedSet(final Collection c,
final float f, CrossHash.IHasher hasher) {
this(c.size(), f, hasher);
addAll(c);
}
/**
* Creates a new hash set with {@link #DEFAULT_LOAD_FACTOR} as load
* factor copying a given collection.
*
* @param c a {@link Collection} to be copied into the new hash set.
* @param hasher used to hash items; typically only needed when K is an array, where CrossHash has implementations
*/
public OrderedSet(final Collection c, CrossHash.IHasher hasher) {
this(c, DEFAULT_LOAD_FACTOR, hasher);
}
/**
* Creates a new hash set and fills it with the elements of a given array.
*
* @param a an array whose elements will be used to fill the set.
* @param offset the first element to use.
* @param length the number of elements to use.
* @param f the load factor.
*/
public OrderedSet(final K[] a, final int offset,
final int length, final float f, CrossHash.IHasher hasher) {
this(length < 0 ? 0 : length, f, hasher);
if (a == null) throw new NullPointerException("Array passed to OrderedSet constructor cannot be null");
if (offset < 0) throw new ArrayIndexOutOfBoundsException("Offset (" + offset + ") is negative");
if (length < 0) throw new IllegalArgumentException("Length (" + length + ") is negative");
if (offset + length > a.length) {
throw new ArrayIndexOutOfBoundsException(
"Last index (" + (offset + length) + ") is greater than array length (" + a.length + ")");
}
for (int i = 0; i < length; i++)
add(a[offset + i]);
}
/**
* Creates a new hash set with {@link #DEFAULT_LOAD_FACTOR} as load
* factor and fills it with the elements of a given array.
*
* @param a an array whose elements will be used to fill the set.
* @param offset the first element to use.
* @param length the number of elements to use.
*/
public OrderedSet(final K[] a, final int offset,
final int length, CrossHash.IHasher hasher) {
this(a, offset, length, DEFAULT_LOAD_FACTOR, hasher);
}
/**
* Creates a new hash set copying the elements of an array.
*
* @param a an array to be copied into the new hash set.
* @param f the load factor.
*/
public OrderedSet(final K[] a, final float f, CrossHash.IHasher hasher) {
this(a, 0, a.length, f, hasher);
}
/**
* Creates a new hash set with {@link #DEFAULT_LOAD_FACTOR} as load
* factor copying the elements of an array.
*
* @param a an array to be copied into the new hash set.
*/
public OrderedSet(final K[] a, CrossHash.IHasher hasher) {
this(a, DEFAULT_LOAD_FACTOR, hasher);
}
private int realSize() {
return containsNull ? size - 1 : size;
}
private void ensureCapacity(final int capacity) {
final int needed = arraySize(capacity, f);
if (needed > n)
rehash(needed);
}
private void tryCapacity(final long capacity) {
final int needed = (int) Math.min(
1 << 30,
Math.max(2, HashCommon.nextPowerOfTwo((long) Math.ceil(capacity
/ f))));
if (needed > n)
rehash(needed);
}
public boolean addAll(Collection c) {
int n = c.size();
// The resulting collection will be at least c.size() big
if (f <= .5)
ensureCapacity(n); // The resulting collection will be sized
// for c.size() elements
else
tryCapacity(size() + n); // The resulting collection will be
// tentatively sized for size() + c.size() elements
boolean retVal = false;
final Iterator i = c.iterator();
while (n-- != 0)
if (add(i.next()))
retVal = true;
return retVal;
}
public boolean addAll(K[] a) {
if(a == null)
return false;
int n = a.length;
// The resulting collection will be at least a.length big
if (f <= .5)
ensureCapacity(n); // The resulting collection will be sized
// for a.length elements
else
tryCapacity(size() + n); // The resulting collection will be
// tentatively sized for size() + a.length elements
boolean retVal = false;
for (int i = 0; i < n; i++) {
if(add(a[i]))
retVal = true;
}
return retVal;
}
public boolean add(final K k) {
int pos;
if (k == null) {
if (containsNull)
return false;
pos = n;
containsNull = true;
} else {
K curr;
final K[] key = this.key;
// The starting point.
if (!((curr = key[pos = (hasher.hash(k)) & mask]) == null)) {
if (hasher.areEqual(curr, k))
return false;
while (!((curr = key[pos = pos + 1 & mask]) == null))
if (hasher.areEqual(curr, k))
return false;
}
key[pos] = k;
}
order.add(pos);
if (size++ >= maxFill)
rehash(arraySize(size + 1, f));
return true;
}
public boolean addAt(final K k, final int idx) {
// if (idx <= 0)
// return addAndMoveToFirst(k);
// else if (idx >= size)
// return addAndMoveToLast(k);
int pos;
if (k == null) {
if (containsNull)
return false;
pos = n;
containsNull = true;
} else {
K curr;
final K[] key = this.key;
// The starting point.
if (!((curr = key[pos = (hasher.hash(k)) & mask]) == null)) {
if (hasher.areEqual(curr, k))
return false;
while (!((curr = key[pos = pos + 1 & mask]) == null))
if (hasher.areEqual(curr, k))
return false;
}
key[pos] = k;
}
order.insert(idx, pos);
if (size++ >= maxFill)
rehash(arraySize(size + 1, f));
return true;
}
/**
* Add a random element if not present, get the existing value if already
* present.
*
* This is equivalent to (but faster than) doing a:
*
*
* K exist = set.get(k);
* if (exist == null) {
* set.add(k);
* exist = k;
* }
*
*/
public K addOrGet(final K k) {
int pos;
if (k == null) {
if (containsNull)
return key[n];
pos = n;
containsNull = true;
} else {
K curr;
final K[] key = this.key;
// The starting point.
if (!((curr = key[pos = (hasher.hash(k)) & mask]) == null)) {
if (hasher.areEqual(curr, k))
return curr;
while (!((curr = key[pos = pos + 1 & mask]) == null))
if (hasher.areEqual(curr, k))
return curr;
}
key[pos] = k;
}
order.add(pos);
if (size++ >= maxFill)
rehash(arraySize(size + 1, f));
return k;
}
/**
* Shifts left entries with the specified hash code, starting at the
* specified position, and empties the resulting free entry.
*
* @param pos a starting position.
*/
protected final void shiftKeys(int pos) {
// Shift entries with the same hash.
int last, slot;
K curr;
final K[] key = this.key;
for (; ; ) {
pos = (last = pos) + 1 & mask;
for (; ; ) {
if ((curr = key[pos]) == null) {
key[last] = null;
return;
}
slot = (hasher.hash(curr))
& mask;
if (last <= pos ? last >= slot || slot > pos : last >= slot
&& slot > pos)
break;
pos = pos + 1 & mask;
}
key[last] = curr;
fixOrder(pos, last);
}
}
private boolean removeEntry(final int pos) {
size--;
fixOrder(pos);
shiftKeys(pos);
if (size < maxFill / 4 && n > DEFAULT_INITIAL_SIZE)
rehash(n / 2);
return true;
}
private boolean removeNullEntry() {
containsNull = false;
key[n] = null;
size--;
fixOrder(n);
if (size < maxFill / 4 && n > DEFAULT_INITIAL_SIZE)
rehash(n / 2);
return true;
}
@SuppressWarnings("unchecked")
protected boolean rem(final Object k) {
if (k == null)
return containsNull && removeNullEntry();
K curr;
final K[] key = this.key;
int pos;
// The starting point.
if ((curr = key[pos = (hasher.hash(k)) & mask]) == null)
return false;
if (hasher.areEqual(k, curr))
return removeEntry(pos);
while (true) {
if ((curr = key[pos = pos + 1 & mask]) == null)
return false;
if (hasher.areEqual(k, curr))
return removeEntry(pos);
}
}
@Override
public boolean remove(final Object o) {
return rem(o);
}
/**
* Removes the first key in iteration order.
*
* @return the first key.
* @throws NoSuchElementException is this set is empty.
*/
public K removeFirst() {
if (size == 0)
throw new NoSuchElementException();
final int pos = order.removeIndex(0);
final K k = key[pos];
size--;
if (k == null) {
containsNull = false;
key[n] = null;
} else
shiftKeys(pos);
if (size < maxFill / 4 && n > DEFAULT_INITIAL_SIZE)
rehash(n / 2);
return k;
}
/**
* Removes the the last key in iteration order.
*
* @return the last key.
* @throws NoSuchElementException is this set is empty.
*/
public K removeLast() {
if (size == 0)
throw new NoSuchElementException();
final int pos = order.pop();
// Abbreviated version of fixOrder(pos)
/*
last = (int) (link[pos] >>> 32);
if (0 <= last) {
// Special case of SET_NEXT( link[ last ], -1 )
link[last] |= -1 & 0xFFFFFFFFL;
}*/
final K k = key[pos];
size--;
if (k == null) {
containsNull = false;
key[n] = null;
} else
shiftKeys(pos);
if (size < maxFill / 4 && n > DEFAULT_INITIAL_SIZE)
rehash(n / 2);
return k;
}
private void moveIndexToFirst(final int i) {
if (size <= 1 || order.items[0] == i)
return;
order.moveToFirst(i);
}
private void moveIndexToLast(final int i) {
if (size <= 1 || order.items[order.size-1] == i)
return;
order.moveToLast(i);
}
/**
* Adds a key to the set; if the key is already present, it is moved to the
* first position of the iteration order.
*
* @param k the key.
* @return true if the key was not present.
*/
public boolean addAndMoveToFirst(final K k) {
int pos;
if (k == null) {
if (containsNull) {
moveIndexToFirst(n);
return false;
}
containsNull = true;
pos = n;
} else {
// The starting point.
final K[] key = this.key;
pos = (hasher.hash(k)) & mask;
while (!(key[pos] == null)) {
if (hasher.areEqual(k, key[pos])) {
moveIndexToFirst(pos);
return false;
}
pos = pos + 1 & mask;
}
}
key[pos] = k;
order.insert(0, pos);
if (size++ >= maxFill)
rehash(arraySize(size, f));
return true;
}
/**
* Adds a key to the set; if the key is already present, it is moved to the
* last position of the iteration order.
*
* @param k the key.
* @return true if the key was not present.
*/
public boolean addAndMoveToLast(final K k) {
int pos;
if (k == null) {
if (containsNull) {
moveIndexToLast(n);
return false;
}
containsNull = true;
pos = n;
} else {
// The starting point.
final K[] key = this.key;
pos = (hasher.hash(k)) & mask;
// There's always an unused entry.
while (!(key[pos] == null)) {
if (hasher.areEqual(k, key[pos])) {
moveIndexToLast(pos);
return false;
}
pos = pos + 1 & mask;
}
}
key[pos] = k;
order.add(pos);
if (size++ >= maxFill)
rehash(arraySize(size, f));
return true;
}
/**
* Returns the element of this set that is equal to the given key, or
* null.
*
* @return the element of this set that is equal to the given key, or
* null.
*/
public K get(final Object k) {
if (k == null)
return key[n]; // This is correct independently of the value of
// containsNull and of the map being custom
K curr;
final K[] key = this.key;
int pos;
// The starting point.
if ((curr = key[pos = (hasher.hash(k)) & mask]) == null)
return null;
if (hasher.areEqual(k, curr))
return curr;
// There's always an unused entry.
while (true) {
if ((curr = key[pos = pos + 1 & mask]) == null)
return null;
if (hasher.areEqual(k, curr))
return curr;
}
}
public boolean contains(final Object k) {
if (k == null)
return containsNull;
K curr;
final K[] key = this.key;
int pos;
// The starting point.
if ((curr = key[pos = (hasher.hash(k)) & mask]) == null)
return false;
if (hasher.areEqual(k, curr))
return true;
// There's always an unused entry.
while (true) {
if ((curr = key[pos = pos + 1 & mask]) == null)
return false;
if (hasher.areEqual(k, curr))
return true;
}
}
protected int positionOf(final Object k) {
if (k == null)
{
if(containsNull)
return n;
else
return -1;
}
K curr;
final K[] key = this.key;
int pos;
// The starting point.
if ((curr = key[pos = (hasher.hash(k)) & mask]) == null)
return -1;
if (hasher.areEqual(k, curr))
return pos;
// There's always an unused entry.
while (true) {
if ((curr = key[pos = pos + 1 & mask]) == null)
return -1;
if (hasher.areEqual(k, curr))
return pos;
}
}
/**
* Gets the position in the ordering of the given key, though not as efficiently as some data structures can do it
* (e.g. {@link Arrangement} can access ordering position very quickly but doesn't store other values on its own).
* Returns a value that is at least 0 if it found k, or -1 if k was not present.
* @param k a key or possible key that this should find the index of
* @return the index of k, if present, or -1 if it is not present in this OrderedSet
*/
public int indexOf(final Object k)
{
int pos = positionOf(k);
return (pos < 0) ? -1 : order.indexOf(pos);
}
/**
* Swaps the positions in the ordering for the given items, if they are both present. Returns true if the ordering
* changed as a result of this call, or false if it stayed the same (which can be because left or right was not
* present, or because left and right are the same reference (so swapping would do nothing)).
* @param left an item that should be present in this OrderedSet
* @param right an item that should be present in this OrderedSet
* @return true if this OrderedSet changed in ordering as a result of this call, or false otherwise
*/
public boolean swap(final K left, final K right)
{
if(left == right) return false;
int l = indexOf(left);
if(l < 0) return false;
int r = indexOf(right);
if(r < 0) return false;
order.swap(l, r);
return true;
}
/**
* Swaps the given indices in the ordering, if they are both ints between 0 and size. Returns true if the ordering
* changed as a result of this call, or false if it stayed the same (which can be because left or right referred to
* an out-of-bounds index, or because left and right are equal (so swapping would do nothing)).
* @param left an index of an item in this OrderedSet, at least 0 and less than {@link #size()}
* @param right an index of an item in this OrderedSet, at least 0 and less than {@link #size()}
* @return true if this OrderedSet changed in ordering as a result of this call, or false otherwise
*/
public boolean swapIndices(final int left, final int right)
{
if(left < 0 || right < 0 || left >= order.size || right >= order.size || left == right) return false;
order.swap(left, right);
return true;
}
/*
* Removes all elements from this set.
*
* To increase object reuse, this method does not change the table size.
* If you want to reduce the table size, you must use {@link #trim()}.
*/
public void clear() {
if (size == 0)
return;
size = 0;
containsNull = false;
Arrays.fill(key, null);
order.clear();
}
public int size() {
return size;
}
/**
* Checks whether this collection contains all elements from the given
* collection.
*
* @param c a collection.
* @return true if this collection contains all elements of the
* argument.
*/
public boolean containsAll(Collection c) {
int n = c.size();
final Iterator i = c.iterator();
while (n-- != 0)
if (!contains(i.next()))
return false;
return true;
}
/**
* Retains in this collection only elements from the given collection.
*
* @param c a collection.
* @return true if this collection changed as a result of the
* call.
*/
public boolean retainAll(Collection c) {
boolean retVal = false;
int n = size();
final Iterator i = iterator();
while (n-- != 0) {
if (!c.contains(i.next())) {
i.remove();
retVal = true;
}
}
return retVal;
}
/**
* Remove from this collection all elements in the given collection. If the
* collection is an instance of this class, it uses faster iterators.
*
* @param c a collection.
* @return true if this collection changed as a result of the
* call.
*/
public boolean removeAll(Collection c) {
boolean retVal = false;
int n = c.size();
final Iterator i = c.iterator();
while (n-- != 0)
if (remove(i.next()))
retVal = true;
return retVal;
}
public boolean isEmpty() {
return size() == 0;
}
/**
* Modifies the link vector so that the given entry is removed. This method will complete in linear time.
*
* @param i the index of an entry.
*/
protected int fixOrder(final int i) {
if (size == 0) {
order.clear();
return 0;
}
int idx = order.removeValue(i);
return idx;
}
/**
* Modifies the ordering for a shift from s to d.
*
* This method will complete in linear time or better.
*
* @param s the source position.
* @param d the destination position.
*/
protected void fixOrder(int s, int d) {
if(size == 0)
return;
if (size == 1 || order.items[0] == s) {
order.set(0, d);
} else if (order.items[order.size-1] == s) {
order.set(order.size - 1, d);
} else {
order.set(order.indexOf(s), d);
}
}
/**
* Returns the first element of this set in iteration order.
*
* @return the first element in iteration order.
*/
public K first() {
if (size == 0)
throw new NoSuchElementException();
return key[order.items[0]];
}
/**
* Returns the last element of this set in iteration order.
*
* @return the last element in iteration order.
*/
public K last() {
if (size == 0)
throw new NoSuchElementException();
return key[order.items[order.size-1]];
}
public SortedSet tailSet(K from) {
throw new UnsupportedOperationException();
}
public SortedSet headSet(K to) {
throw new UnsupportedOperationException();
}
public SortedSet subSet(K from, K to) {
throw new UnsupportedOperationException();
}
public Comparator comparator() {
return null;
}
/**
* A list iterator over a linked set.
*
*
* This class provides a list iterator over a linked hash set. The
* constructor runs in constant time.
*/
private class SetIterator implements ListIterator {
/**
* The entry that will be returned by the next call to
* {@link java.util.ListIterator#previous()} (or null if no
* previous entry exists).
*/
int prev = -1;
/**
* The entry that will be returned by the next call to
* {@link java.util.ListIterator#next()} (or null if no
* next entry exists).
*/
int next = -1;
/**
* The last entry that was returned (or -1 if we did not iterate or used
* {@link #remove()}).
*/
int curr = -1;
/**
* The current index (in the sense of a {@link java.util.ListIterator}).
* When -1, we do not know the current index.
*/
int index = -1;
SetIterator() {
next = size == 0 ? -1 : order.items[0];
index = 0;
}
public boolean hasNext() {
return next != -1;
}
public boolean hasPrevious() {
return prev != -1;
}
public K next() {
if (!hasNext())
throw new NoSuchElementException();
curr = next;
if (++index >= order.size)
next = -1;
else
next = order.get(index);//(int) link[curr];
prev = curr;
return key[curr];
}
public K previous() {
if (!hasPrevious())
throw new NoSuchElementException();
curr = prev;
if (--index < 1)
prev = -1;
else
prev = order.get(index - 1);
next = curr;
return key[curr];
}
private void ensureIndexKnown() {
if (index >= 0)
return;
if (prev == -1) {
index = 0;
return;
}
if (next == -1) {
index = size;
return;
}
index = 0;
}
public int nextIndex() {
ensureIndexKnown();
return index + 1;
}
public int previousIndex() {
ensureIndexKnown();
return index - 1;
}
public void remove() {
ensureIndexKnown();
if (curr == -1)
throw new IllegalStateException();
if (curr == prev) {
/*
* If the last operation was a next(), we are removing an entry
* that precedes the current index, and thus we must decrement
* it.
*/
if (--index >= 1)
prev = order.get(index - 1); //(int) (link[curr] >>> 32);
else
prev = -1;
} else {
if (index < order.size - 1)
next = order.get(index + 1);
else
next = -1;
}
order.removeIndex(index);
size--;
int last, slot, pos = curr;
curr = -1;
if (pos == n) {
containsNull = false;
key[n] = null;
//order.removeValue(pos);
} else {
K curr;
final K[] key = OrderedSet.this.key;
// We have to horribly duplicate the shiftKeys() code because we
// need to update next/prev.
for (; ; ) {
pos = (last = pos) + 1 & mask;
for (; ; ) {
if ((curr = key[pos]) == null) {
key[last] = null;
return;
}
slot = (hasher.hash(curr)) & mask;
if (last <= pos
? last >= slot || slot > pos
: last >= slot && slot > pos)
break;
pos = pos + 1 & mask;
}
key[last] = curr;
if (next == pos)
next = last;
if (prev == pos)
prev = last;
fixOrder(pos, last);
}
}
}
/**
* Replaces the last element returned by {@link #next} or
* {@link #previous} with the specified element (optional operation).
* This call can be made only if neither {@link #remove} nor {@link
* #add} have been called after the last call to {@code next} or
* {@code previous}.
*
* @param k the element with which to replace the last element returned by
* {@code next} or {@code previous}
* @throws UnsupportedOperationException if the {@code set} operation
* is not supported by this list iterator
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this list
* @throws IllegalArgumentException if some aspect of the specified
* element prevents it from being added to this list
* @throws IllegalStateException if neither {@code next} nor
* {@code previous} have been called, or {@code remove} or
* {@code add} have been called after the last call to
* {@code next} or {@code previous}
*/
@Override
public void set(K k) {
throw new UnsupportedOperationException("set() not supported on OrderedSet iterator");
}
/**
* Inserts the specified element into the list (optional operation).
* The element is inserted immediately before the element that
* would be returned by {@link #next}, if any, and after the element
* that would be returned by {@link #previous}, if any. (If the
* list contains no elements, the new element becomes the sole element
* on the list.) The new element is inserted before the implicit
* cursor: a subsequent call to {@code next} would be unaffected, and a
* subsequent call to {@code previous} would return the new element.
* (This call increases by one the value that would be returned by a
* call to {@code nextIndex} or {@code previousIndex}.)
*
* @param k the element to insert
* @throws UnsupportedOperationException if the {@code add} method is
* not supported by this list iterator
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this list
* @throws IllegalArgumentException if some aspect of this element
* prevents it from being added to this list
*/
@Override
public void add(K k) {
throw new UnsupportedOperationException("add() not supported on OrderedSet iterator");
}
}
public ListIterator iterator() {
return new SetIterator();
}
/**
* Rehashes the map, making the table as small as possible.
*
*
This method rehashes the table to the smallest size satisfying the load factor. It can be used when the set will not be changed anymore, so to optimize access speed and size.
*
*
If the table size is already the minimum possible, this method does nothing.
*
* @return true if there was enough memory to trim the map.
* @see #trim(int)
*/
public boolean trim() {
final int l = arraySize(size, f);
if (l >= n || size > maxFill(l, f)) return true;
try {
rehash(l);
} catch (Exception cantDoIt) {
return false;
}
return true;
}
/**
* Rehashes this map if the table is too large.
*
*
Let N be the smallest table size that can hold max(n,{@link #size()}) entries, still satisfying the load factor. If the current table size is smaller than or equal to
* N, this method does nothing. Otherwise, it rehashes this map in a table of size N.
*
*
This method is useful when reusing maps. {@linkplain #clear() Clearing a map} leaves the table size untouched. If you are reusing a map many times, you can call this method with a typical
* size to avoid keeping around a very large table just because of a few large transient maps.
*
* @param n the threshold for the trimming.
* @return true if there was enough memory to trim the map.
* @see #trim()
*/
public boolean trim(final int n) {
final int l = HashCommon.nextPowerOfTwo((int) Math.ceil(n / f));
if (l >= n || size > maxFill(l, f)) return true;
try {
rehash(l);
} catch (Exception cantDoIt) {
return false;
}
return true;
}
/**
* Rehashes the map.
*
*
* This method implements the basic rehashing strategy, and may be overriden
* by subclasses implementing different rehashing strategies (e.g.,
* disk-based rehashing). However, you should not override this method
* unless you understand the internal workings of this class.
*
* @param newN the new size
*/
@SuppressWarnings("unchecked")
protected void rehash(final int newN) {
final K[] key = this.key;
final int mask = newN - 1; // Note that this is used by the hashing
// macro
final K[] newKey = (K[]) new Object[newN + 1];
K k;
int i, pos, sz = order.size;
final int[] oi = order.items;
for (int q = 0; q < sz; q++) {
i = oi[q];
if ((k = key[i]) == null)
pos = newN;
else {
pos = (hasher.hash(k)) & mask;
while (!(newKey[pos] == null))
pos = pos + 1 & mask;
}
newKey[pos] = k;
oi[q] = pos;
}
n = newN;
this.mask = mask;
maxFill = maxFill(n, f);
this.key = newKey;
}
/*
@SuppressWarnings("unchecked")
protected void rehash(final int newN) {
final K key[] = this.key;
final V value[] = this.value;
final int mask = newN - 1; // Note that this is used by the hashing
// macro
final K newKey[] = (K[]) new Object[newN + 1];
final V newValue[] = (V[]) new Object[newN + 1];
int i = first, prev = -1, newPrev = -1, t, pos;
final long link[] = this.link;
final long newLink[] = new long[newN + 1];
first = -1;
for (int j = size; j-- != 0;) {
if (((key[i]) == null))
pos = newN;
else {
pos = (((key[i]).hashCode())) & mask;
while (!((newKey[pos]) == null))
pos = (pos + 1) & mask;
}
newKey[pos] = key[i];
newValue[pos] = value[i];
if (prev != -1) {
newLink[newPrev] ^= ((newLink[newPrev] ^ (pos & 0xFFFFFFFFL)) & 0xFFFFFFFFL);
newLink[pos] ^= ((newLink[pos] ^ ((newPrev & 0xFFFFFFFFL) << 32)) & 0xFFFFFFFF00000000L);
newPrev = pos;
} else {
newPrev = first = pos;
// Special case of SET(newLink[ pos ], -1, -1);
newLink[pos] = -1L;
}
t = i;
i = (int) link[i];
prev = t;
}
this.link = newLink;
this.last = newPrev;
if (newPrev != -1)
// Special case of SET_NEXT( newLink[ newPrev ], -1 );
newLink[newPrev] |= -1 & 0xFFFFFFFFL;
n = newN;
this.mask = mask;
maxFill = maxFill(n, f);
this.key = newKey;
this.value = newValue;
}
*/
/**
* Returns a deep copy of this map.
*
*
* This method performs a deep copy of this hash map; the data stored in the
* map, however, is not cloned. Note that this makes a difference only for
* object keys.
*
* @return a deep copy of this map.
*/
@SuppressWarnings("unchecked")
@GwtIncompatible
public Object clone() {
OrderedSet c;
try {
c = new OrderedSet<>(hasher);
c.key = (K[]) new Object[n + 1];
System.arraycopy(key, 0, c.key, 0, n + 1);
c.order = (IntVLA) order.clone();
return c;
} catch (Exception cantHappen) {
throw new UnsupportedOperationException(cantHappen + (cantHappen.getMessage() != null ?
"; " + cantHappen.getMessage() : ""));
}
}
/**
* Returns a hash code for this set.
*
* This method overrides the generic method provided by the superclass.
* Since equals() is not overriden, it is important that the
* value returned by this method is the same value as the one returned by
* the overriden method.
*
* @return a hash code for this set.
*/
public int hashCode() {
int h = 0;
for (int j = realSize(), i = 0; j-- != 0; ) {
while (key[i] == null)
i++;
if (this != key[i])
h += hasher.hash(key[i]);
i++;
}
// Zero / null have hash zero.
return h;
}
public long hash64()
{
long seed = 9069147967908697017L;
final int len = order.size;
final int[] data = order.items;
for (int i = 3; i < len; i+=4) {
seed = mum(
mum(Objects.hashCode(key[data[i-3]]) ^ b1, Objects.hashCode(key[data[i-2]]) ^ b2) + seed,
mum(Objects.hashCode(key[data[i-1]]) ^ b3, Objects.hashCode(key[data[i]]) ^ b4));
}
switch (len & 3) {
case 0: seed = mum(b1 ^ seed, b4 + seed); break;
case 1: seed = mum(seed ^ Objects.hashCode(key[data[len-1]]) >>> 16, b3 ^ (Objects.hashCode(key[data[len-1]]) & 0xFFFFL)); break;
case 2: seed = mum(seed ^ Objects.hashCode(key[data[len-2]]), b0 ^ Objects.hashCode(key[data[len-1]])); break;
case 3: seed = mum(seed ^ Objects.hashCode(key[data[len-3]]), b2 ^ Objects.hashCode(key[data[len-2]])) ^ mum(seed ^ Objects.hashCode(key[data[len-1]]), b4); break;
}
seed = (seed ^ seed << 16) * (len ^ b0);
return seed - (seed >>> 31) + (seed << 33);
}
/**
* Returns the maximum number of entries that can be filled before rehashing.
*
* @param n the size of the backing array.
* @param f the load factor.
* @return the maximum number of entries before rehashing.
*/
public static int maxFill(final int n, final float f) {
/* We must guarantee that there is always at least
* one free entry (even with pathological load factors). */
return Math.min((int) Math.ceil(n * f), n - 1);
}
/**
* Returns the maximum number of entries that can be filled before rehashing.
*
* @param n the size of the backing array.
* @param f the load factor.
* @return the maximum number of entries before rehashing.
*/
public static long maxFill(final long n, final float f) {
/* We must guarantee that there is always at least
* one free entry (even with pathological load factors). */
return Math.min((long) Math.ceil(n * f), n - 1);
}
/**
* Returns the least power of two smaller than or equal to 230 and larger than or equal to Math.ceil( expected / f ).
*
* @param expected the expected number of elements in a hash table.
* @param f the load factor.
* @return the minimum possible size for a backing array.
* @throws IllegalArgumentException if the necessary size is larger than 230.
*/
public static int arraySize(final int expected, final float f) {
final long s = Math.max(2, HashCommon.nextPowerOfTwo((long) Math.ceil(expected / f)));
if (s > 1 << 30)
throw new IllegalArgumentException("Too large (" + expected + " expected elements with load factor " + f + ")");
return (int) s;
}
@Override
public Object[] toArray() {
final Object[] a = new Object[size()];
objectUnwrap(iterator(), a);
return a;
}
@SuppressWarnings("unchecked")
@Override
public T[] toArray(T[] a) {
final int size = size();
objectUnwrap(iterator(), a);
if (size < a.length)
a[size] = null;
return a;
}
/**
* Unwraps an iterator into an array starting at a given offset for a given number of elements.
*
*
This method iterates over the given type-specific iterator and stores the elements returned, up to a maximum of length, in the given array starting at offset. The
* number of actually unwrapped elements is returned (it may be less than max if the iterator emits less than max elements).
*
* @param i a type-specific iterator.
* @param array an array to contain the output of the iterator.
* @param offset the first element of the array to be returned.
* @param max the maximum number of elements to unwrap.
* @return the number of elements unwrapped.
*/
private static int objectUnwrap(final Iterator i, final K[] array, int offset, final int max) {
if (max < 0) throw new IllegalArgumentException("The maximum number of elements (" + max + ") is negative");
if (offset < 0 || offset + max > array.length) throw new IllegalArgumentException();
int j = max;
while (j-- != 0 && i.hasNext())
array[offset++] = i.next();
return max - j - 1;
}
/**
* Unwraps an iterator into an array.
*
*
This method iterates over the given type-specific iterator and stores the elements returned in the given array. The iteration will stop when the iterator has no more elements or when the end
* of the array has been reached.
*
* @param i a type-specific iterator.
* @param array an array to contain the output of the iterator.
* @return the number of elements unwrapped.
*/
private static int objectUnwrap(final Iterator i, final K[] array) {
return objectUnwrap(i, array, 0, array.length);
}
@Override
public String toString() {
final StringBuilder s = new StringBuilder();
int n = size(), i = 0;
boolean first = true;
s.append("OrderedSet{");
while (i < n) {
if (first) first = false;
else s.append(", ");
K k = getAt(i++);
s.append(k == this ? "(this collection)" : String.valueOf(k));
}
s.append("}");
return s.toString();
}
@Override
public boolean equals(final Object o) {
if (o == this)
return true;
if (!(o instanceof Set))
return false;
Set s = (Set) o;
if (s.size() != size())
return false;
return containsAll(s);
}
@GwtIncompatible
private void writeObject(java.io.ObjectOutputStream s)
throws java.io.IOException {
final ListIterator i = iterator();
s.defaultWriteObject();
for (int j = size; j-- != 0; )
s.writeObject(i.next());
}
@GwtIncompatible
@SuppressWarnings("unchecked")
private void readObject(java.io.ObjectInputStream s)
throws java.io.IOException, ClassNotFoundException {
s.defaultReadObject();
n = arraySize(size, f);
maxFill = maxFill(n, f);
mask = n - 1;
final K[] key = this.key = (K[]) new Object[n + 1];
final IntVLA order = this.order = new IntVLA(n + 1);
K k;
for (int i = size, pos; i-- != 0; ) {
k = (K) s.readObject();
if (k == null) {
pos = n;
containsNull = true;
} else {
if (!(key[pos = (hasher.hash(k)) & mask] == null))
while (!(key[pos = pos + 1 & mask] == null)) ;
}
key[pos] = k;
order.add(pos);
}
}
/**
* Gets the item at the given index in the iteration order in constant time (random-access).
*
* @param idx the index in the iteration order of the key to fetch
* @return the key at the index, if the index is valid, otherwise null
*/
public K getAt(final int idx) {
if (idx < 0 || idx >= order.size)
return null;
final K[] key = this.key;
// The starting point.
return key[order.get(idx)];
}
/**
* Removes the item at the given index in the iteration order in not-exactly constant time (though it still should
* be efficient).
*
* @param idx the index in the iteration order of the item to remove
* @return true if this Set was changed as a result of this call, or false if nothing changed.
*/
public boolean removeAt(final int idx) {
if (idx < 0 || idx >= order.size)
throw new NoSuchElementException();
int pos = order.get(idx);
if (key[pos] == null) {
if (containsNull)
return removeNullEntry();
return false;
}
return removeEntry(pos);
}
/**
* Gets a random value from this OrderedSet in constant time, using the given IRNG to generate a random number.
*
* @param rng used to generate a random index for a value
* @return a random value from this OrderedSet
*/
public K randomItem(IRNG rng) {
return getAt(rng.nextInt(order.size));
}
/**
* Randomly alters the iteration order for this OrderedSet using the given IRNG to shuffle.
*
* @param rng used to generate a random ordering
* @return this for chaining
*/
public OrderedSet shuffle(IRNG rng) {
if (size < 2 || rng == null)
return this;
order.shuffle(rng);
return this;
}
/**
* Given an array or varargs of replacement indices for this OrderedSet's iteration order, reorders this so the
* first item in the returned version is the same as {@code getAt(ordering[0])} (with some care taken for negative
* or too-large indices), the second item in the returned version is the same as {@code getAt(ordering[1])}, etc.
*
* Negative indices are considered reversed distances from the end of ordering, so -1 refers to the same index as
* {@code ordering[ordering.length - 1]}. If ordering is smaller than {@code size()}, only the indices up to the
* length of ordering will be modified. If ordering is larger than {@code size()}, only as many indices will be
* affected as {@code size()}, and reversed distances are measured from the end of this Set's entries instead of
* the end of ordering. Duplicate values in ordering will produce duplicate values in the returned Set.
*
* This method modifies this OrderedSet in-place and also returns it for chaining.
*
* @param ordering an array or varargs of int indices, where the nth item in ordering changes the nth item in this
* Set to have the value currently in this Set at the index specified by the value in ordering
* @return this for chaining, after modifying it in-place
*/
public OrderedSet reorder(int... ordering) {
order.reorder(ordering);
return this;
}
private boolean alterEntry(final int pos, final K replacement) {
int rep;
if (replacement == null) {
if (containsNull)
return false;
rep = n;
containsNull = true;
} else {
K curr;
final K[] key = this.key;
shiftKeys(pos);
// The starting point.
if (!((curr = key[rep = (hasher.hash(replacement)) & mask]) == null)) {
if (hasher.areEqual(curr, replacement))
return false;
while (!((curr = key[rep = rep + 1 & mask]) == null))
if (hasher.areEqual(curr, replacement))
return false;
}
key[rep] = replacement;
}
fixOrder(pos, rep);
return true;
}
private boolean alterNullEntry(final K replacement) {
containsNull = false;
key[n] = null;
int rep;
if (replacement == null) {
rep = n;
containsNull = true;
} else {
K curr;
final K[] key = this.key;
// The starting point.
if (!((curr = key[rep = (hasher.hash(replacement)) & mask]) == null)) {
if (hasher.areEqual(curr, replacement))
return false;
while (!((curr = key[rep = rep + 1 & mask]) == null))
if (hasher.areEqual(curr, replacement))
return false;
}
key[rep] = replacement;
}
fixOrder(n, rep);
return true;
}
/*
public boolean alter(K original, K replacement)
{
if (original == null) {
if (containsNull) {
return replacement != null && alterNullEntry(replacement);
}
else
return add(replacement);
}
else if(hasher.areEqual(original, replacement))
return false;
K curr;
final K[] key = this.key;
int pos;
// The starting point.
if ((curr = key[pos = (hasher.hash(original)) & mask]) == null)
return add(replacement);
if (hasher.areEqual(original, curr))
return alterEntry(pos, replacement);
while (true) {
if ((curr = key[pos = (pos + 1) & mask]) == null)
return add(replacement);
if (hasher.areEqual(original, curr))
return alterEntry(pos, replacement);
}
}*/
private int alterEntry(final int pos) {
int idx = fixOrder(pos);
size--;
shiftKeys(pos);
if (size < maxFill >> 2 && n > DEFAULT_INITIAL_SIZE)
rehash(n >> 1);
return idx;
}
private int alterNullEntry() {
int idx = fixOrder(n);
containsNull = false;
size--;
if (size < maxFill >> 2 && n > DEFAULT_INITIAL_SIZE)
rehash(n >> 1);
return idx;
}
/**
* Changes a K, original, to another, replacement, while keeping replacement at the same point in the ordering.
*
* @param original a K value that will be removed from this Set if present, and its iteration index remembered
* @param replacement another K value that will replace original at the remembered index
* @return true if the Set changed, or false if it didn't (such as if the two arguments are equal, or replacement was already in the Set but original was not)
*/
public boolean alter(K original, K replacement) {
int idx;
if (original == null) {
if (containsNull) {
if (replacement != null) {
idx = alterNullEntry();
addAt(replacement, idx);
return true;
} else
return false;
}
;
return false;
}
if (hasher.areEqual(original, replacement))
return false;
K curr;
final K[] key = this.key;
int pos;
// The starting point.
if ((curr = key[pos = (hasher.hash(original)) & mask]) == null)
return false;
if (hasher.areEqual(original, curr)) {
idx = alterEntry(pos);
addAt(replacement, idx);
return true;
}
while (true) {
if ((curr = key[pos = pos + 1 & mask]) == null)
return false;
if (hasher.areEqual(original, curr)) {
idx = alterEntry(pos);
addAt(replacement, idx);
return true;
}
}
}
/**
* Changes the K at the given index to replacement while keeping replacement at the same point in the ordering.
*
* @param index an index to replace the K item at
* @param replacement another K value that will replace the original at the remembered index
* @return true if the Set changed, or false if it didn't (such as if the replacement was already present at the given index)
*/
public boolean alterAt(int index, K replacement)
{
return alter(getAt(index), replacement);
}
/**
* Sorts this whole OrderedSet using the supplied Comparator.
* @param comparator a Comparator that can be used on the same type this uses for its keys (may need wildcards)
*/
public void sort(Comparator comparator)
{
sort(comparator, 0, size);
}
/**
* Sorts a sub-range of this OrderedSet from what is currently the index {@code start} up to (but not including) the
* index {@code end}, using the supplied Comparator.
* @param comparator a Comparator that can be used on the same type this uses for its keys (may need wildcards)
* @param start the first index of a key to sort (the index can change after this)
* @param end the exclusive bound on the indices to sort; often this is just {@link #size()}
*/
public void sort(Comparator comparator, int start, int end)
{
TimSort.sort(key, order, start, end, comparator);
}
}