All Downloads are FREE. Search and download functionalities are using the official Maven repository.

it.unimi.dsi.fastutil.doubles.DoubleOpenHashBigSet Maven / Gradle / Ivy

Go to download

fastutil extends the Java Collections Framework by providing type-specific maps, sets, lists, and queues with a small memory footprint and fast access and insertion; it provides also big (64-bit) arrays, sets and lists, sorting algorithms, fast, practical I/O classes for binary and text files, and facilities for memory mapping large files. Note that if you have both this jar and fastutil-core.jar in your dependencies, fastutil-core.jar should be excluded.

There is a newer version: 8.5.15
Show newest version
/*
	* 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 it.unimi.dsi.fastutil.doubles;

import static it.unimi.dsi.fastutil.BigArrays.copy;
import static it.unimi.dsi.fastutil.BigArrays.fill;
import static it.unimi.dsi.fastutil.BigArrays.set;
import it.unimi.dsi.fastutil.BigArrays;
import it.unimi.dsi.fastutil.Hash;
import it.unimi.dsi.fastutil.Size64;
import it.unimi.dsi.fastutil.HashCommon;
import static it.unimi.dsi.fastutil.HashCommon.bigArraySize;
import static it.unimi.dsi.fastutil.HashCommon.maxFill;
import java.util.Collection;
import java.util.Iterator;
import java.util.NoSuchElementException;

/**
 * A type-specific hash big set with with a fast, small-footprint implementation.
 *
 * 

* Instances of this class use a hash table to represent a big set: the number of elements in the * set is limited only by the amount of core memory. The table (backed by a * {@linkplain it.unimi.dsi.fastutil.BigArrays big array}) 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, the table is never reduced * to a size smaller than that at creation time: this approach makes it possible to create sets with * a large capacity in which insertions and deletions do not cause immediately rehashing. Moreover, * 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. * *

* The methods of this class are about 30% slower than those of the corresponding non-big set. * * @see Hash * @see HashCommon */ public class DoubleOpenHashBigSet extends AbstractDoubleSet implements java.io.Serializable, Cloneable, Hash, Size64 { private static final long serialVersionUID = 0L; private static final boolean ASSERTS = false; /** The big array of keys. */ protected transient double[][] key; /** The mask for wrapping a position counter. */ protected transient long mask; /** The mask for wrapping a segment counter. */ protected transient int segmentMask; /** The mask for wrapping a base counter. */ protected transient int baseMask; /** Whether this set contains the null key. */ protected transient boolean containsNull; /** The current table size (always a power of 2). */ protected transient long n; /** Threshold after which we rehash. It must be the table size times {@link #f}. */ protected transient long maxFill; /** We never resize below this threshold, which is the construction-time {#n}. */ protected final transient long minN; /** The acceptable load factor. */ protected final float f; /** Number of entries in the set. */ protected long size; /** Initialises the mask values. */ private void initMasks() { mask = n - 1; /* Note that either we have more than one segment, and in this case all segments * are BigArrays.SEGMENT_SIZE long, or we have exactly one segment whose length * is a power of two. */ segmentMask = key[0].length - 1; baseMask = key.length - 1; } /** * Creates a new hash big set. * *

* The actual table size will be the least power of two greater than {@code expected}/{@code f}. * * @param expected the expected number of elements in the set. * @param f the load factor. */ public DoubleOpenHashBigSet(final long 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 (n < 0) throw new IllegalArgumentException("The expected number of elements must be nonnegative"); this.f = f; minN = n = bigArraySize(expected, f); maxFill = maxFill(n, f); key = DoubleBigArrays.newBigArray(n); initMasks(); } /** * Creates a new hash big set with {@link Hash#DEFAULT_LOAD_FACTOR} as load factor. * * @param expected the expected number of elements in the hash big set. */ public DoubleOpenHashBigSet(final long expected) { this(expected, DEFAULT_LOAD_FACTOR); } /** * Creates a new hash big set with initial expected {@link Hash#DEFAULT_INITIAL_SIZE} elements and * {@link Hash#DEFAULT_LOAD_FACTOR} as load factor. */ public DoubleOpenHashBigSet() { this(DEFAULT_INITIAL_SIZE, DEFAULT_LOAD_FACTOR); } /** * Creates a new hash big set copying a given collection. * * @param c a {@link Collection} to be copied into the new hash big set. * @param f the load factor. */ public DoubleOpenHashBigSet(final Collection c, final float f) { this(Size64.sizeOf(c), f); addAll(c); } /** * Creates a new hash big set with {@link Hash#DEFAULT_LOAD_FACTOR} as load factor copying a given * collection. * * @param c a {@link Collection} to be copied into the new hash big set. */ public DoubleOpenHashBigSet(final Collection c) { this(c, DEFAULT_LOAD_FACTOR); } /** * Creates a new hash big set copying a given type-specific collection. * * @param c a type-specific collection to be copied into the new hash big set. * @param f the load factor. */ public DoubleOpenHashBigSet(final DoubleCollection c, final float f) { this(Size64.sizeOf(c), f); addAll(c); } /** * Creates a new hash big set with {@link Hash#DEFAULT_LOAD_FACTOR} as load factor copying a given * type-specific collection. * * @param c a type-specific collection to be copied into the new hash big set. */ public DoubleOpenHashBigSet(final DoubleCollection c) { this(c, DEFAULT_LOAD_FACTOR); } /** * Creates a new hash big set using elements provided by a type-specific iterator. * * @param i a type-specific iterator whose elements will fill the new hash big set. * @param f the load factor. */ public DoubleOpenHashBigSet(final DoubleIterator i, final float f) { this(DEFAULT_INITIAL_SIZE, f); while (i.hasNext()) add(i.nextDouble()); } /** * Creates a new hash big set with {@link Hash#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 new hash big set. */ public DoubleOpenHashBigSet(final DoubleIterator i) { this(i, DEFAULT_LOAD_FACTOR); } /** * Creates a new hash big set using elements provided by an iterator. * * @param i an iterator whose elements will fill the new hash big set. * @param f the load factor. */ public DoubleOpenHashBigSet(final Iterator i, final float f) { this(DoubleIterators.asDoubleIterator(i), f); } /** * Creates a new hash big set with {@link Hash#DEFAULT_LOAD_FACTOR} as load factor using elements * provided by an iterator. * * @param i an iterator whose elements will fill the new hash big set. */ public DoubleOpenHashBigSet(final Iterator i) { this(DoubleIterators.asDoubleIterator(i)); } /** * Creates a new hash big set and fills it with the elements of a given array. * * @param a an array whose elements will be used to fill the new hash big set. * @param offset the first element to use. * @param length the number of elements to use. * @param f the load factor. */ public DoubleOpenHashBigSet(final double[] a, final int offset, final int length, final float f) { this(length < 0 ? 0 : length, f); DoubleArrays.ensureOffsetLength(a, offset, length); for (int i = 0; i < length; i++) add(a[offset + i]); } /** * Creates a new hash big set with {@link Hash#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 new hash big set. * @param offset the first element to use. * @param length the number of elements to use. */ public DoubleOpenHashBigSet(final double[] a, final int offset, final int length) { this(a, offset, length, DEFAULT_LOAD_FACTOR); } /** * Creates a new hash big set copying the elements of an array. * * @param a an array to be copied into the new hash big set. * @param f the load factor. */ public DoubleOpenHashBigSet(final double[] a, final float f) { this(a, 0, a.length, f); } /** * Creates a new hash big set with {@link Hash#DEFAULT_LOAD_FACTOR} as load factor copying the * elements of an array. * * @param a an array to be copied into the new hash big set. */ public DoubleOpenHashBigSet(final double[] a) { this(a, DEFAULT_LOAD_FACTOR); } /** * Collects the result of a primitive {@code Stream} into a new big hash set. * *

* This method performs a terminal operation on the given {@code Stream} * * @apiNote Taking a primitive stream instead of returning something like a * {@link java.util.stream.Collector Collector} is necessary because there is no primitive * {@code Collector} equivalent in the Java API. */ public static DoubleOpenHashBigSet toBigSet(java.util.stream.DoubleStream stream) { return stream.collect(DoubleOpenHashBigSet::new, DoubleOpenHashBigSet::add, DoubleOpenHashBigSet::addAll); } /** * Collects the result of a primitive {@code Stream} into a new big hash set. * *

* This method performs a terminal operation on the given {@code Stream} * * @apiNote Taking a primitive stream instead returning something like a * {@link java.util.stream.Collector Collector} is necessary because there is no primitive * {@code Collector} equivalent in the Java API. */ public static DoubleOpenHashBigSet toBigSetWithExpectedSize(java.util.stream.DoubleStream stream, long expectedSize) { return stream.collect(() -> new DoubleOpenHashBigSet(expectedSize), DoubleOpenHashBigSet::add, DoubleOpenHashBigSet::addAll); } private long realSize() { return containsNull ? size - 1 : size; } private void ensureCapacity(final long capacity) { final long needed = bigArraySize(capacity, f); if (needed > n) rehash(needed); } @Override public boolean addAll(Collection c) { final long size = Size64.sizeOf(c); // The resulting collection will be at least c.size() big if (f <= .5) ensureCapacity(size); // The resulting collection will be sized for c.size() elements else ensureCapacity(size64() + size); // The resulting collection will be sized for size() + c.size() elements return super.addAll(c); } @Override public boolean addAll(DoubleCollection c) { final long size = Size64.sizeOf(c); if (f <= .5) ensureCapacity(size); // The resulting collection will be size for c.size() elements else ensureCapacity(size64() + size); // The resulting collection will be sized for size() + c.size() elements return super.addAll(c); } @Override public boolean add(final double k) { int displ, base; if ((Double.doubleToLongBits(k) == 0)) { if (containsNull) return false; containsNull = true; } else { double curr; final double[][] key = this.key; final long h = it.unimi.dsi.fastutil.HashCommon.mix(Double.doubleToRawLongBits(k)); // The starting point. if (!(Double.doubleToLongBits(curr = key[base = (int)((h & mask) >>> BigArrays.SEGMENT_SHIFT)][displ = (int)(h & segmentMask)]) == 0)) { if ((Double.doubleToLongBits(curr) == Double.doubleToLongBits(k))) return false; while (!(Double.doubleToLongBits(curr = key[base = (base + ((displ = (displ + 1) & segmentMask) == 0 ? 1 : 0)) & baseMask][displ]) == 0)) if ((Double.doubleToLongBits(curr) == Double.doubleToLongBits(k))) return false; } key[base][displ] = k; } if (size++ >= maxFill) rehash(2 * n); if (ASSERTS) checkTable(); return true; } /** * 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(long pos) { // Shift entries with the same hash. long last, slot; final double[][] key = this.key; for (;;) { pos = ((last = pos) + 1) & mask; for (;;) { if ((Double.doubleToLongBits(BigArrays.get(key, pos)) == 0)) { set(key, last, (0)); return; } slot = it.unimi.dsi.fastutil.HashCommon.mix(Double.doubleToRawLongBits(BigArrays.get(key, pos))) & mask; if (last <= pos ? last >= slot || slot > pos : last >= slot && slot > pos) break; pos = (pos + 1) & mask; } set(key, last, BigArrays.get(key, pos)); } } private boolean removeEntry(final int base, final int displ) { size--; shiftKeys(base * (long)BigArrays.SEGMENT_SIZE + displ); if (n > minN && size < maxFill / 4 && n > DEFAULT_INITIAL_SIZE) rehash(n / 2); return true; } private boolean removeNullEntry() { containsNull = false; size--; if (n > minN && size < maxFill / 4 && n > DEFAULT_INITIAL_SIZE) rehash(n / 2); return true; } @Override public boolean remove(final double k) { if ((Double.doubleToLongBits(k) == 0)) { if (containsNull) return removeNullEntry(); return false; } double curr; final double[][] key = this.key; final long h = it.unimi.dsi.fastutil.HashCommon.mix(Double.doubleToRawLongBits(k)); int displ, base; // The starting point. if ((Double.doubleToLongBits(curr = key[base = (int)((h & mask) >>> BigArrays.SEGMENT_SHIFT)][displ = (int)(h & segmentMask)]) == 0)) return false; if ((Double.doubleToLongBits(curr) == Double.doubleToLongBits(k))) return removeEntry(base, displ); while (true) { if ((Double.doubleToLongBits(curr = key[base = (base + ((displ = (displ + 1) & segmentMask) == 0 ? 1 : 0)) & baseMask][displ]) == 0)) return false; if ((Double.doubleToLongBits(curr) == Double.doubleToLongBits(k))) return removeEntry(base, displ); } } @Override public boolean contains(final double k) { if ((Double.doubleToLongBits(k) == 0)) return containsNull; double curr; final double[][] key = this.key; final long h = it.unimi.dsi.fastutil.HashCommon.mix(Double.doubleToRawLongBits(k)); int displ, base; // The starting point. if ((Double.doubleToLongBits(curr = key[base = (int)((h & mask) >>> BigArrays.SEGMENT_SHIFT)][displ = (int)(h & segmentMask)]) == 0)) return false; if ((Double.doubleToLongBits(curr) == Double.doubleToLongBits(k))) return true; while (true) { if ((Double.doubleToLongBits(curr = key[base = (base + ((displ = (displ + 1) & segmentMask) == 0 ? 1 : 0)) & baseMask][displ]) == 0)) return false; if ((Double.doubleToLongBits(curr) == Double.doubleToLongBits(k))) return true; } } /* Removes all elements from this set. * */ /** * {@inheritDoc} * *

* 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(long)}. */ @Override public void clear() { if (size == 0) return; size = 0; containsNull = false; fill(key, (0)); } /** An iterator over a hash big set. */ private class SetIterator implements DoubleIterator { /** * The base of the last entry returned, if positive or zero; initially, the number of components of * the key array. If negative, the last element returned was that of index {@code - base - 1} from * the {@link #wrapped} list. */ int base = key.length; /** The displacement of the last entry returned; initially, zero. */ int displ; /** * The index of the last entry that has been returned (or {@link Long#MIN_VALUE} if {@link #base} is * negative). It is -1 if either we did not return an entry yet, or the last returned entry has been * removed. */ long last = -1; /** A downward counter measuring how many entries must still be returned. */ long c = size; /** A boolean telling us whether we should return the null key. */ boolean mustReturnNull = DoubleOpenHashBigSet.this.containsNull; /** * A lazily allocated list containing elements that have wrapped around the table because of * removals. */ DoubleArrayList wrapped; @Override public boolean hasNext() { return c != 0; } @Override public double nextDouble() { if (!hasNext()) throw new NoSuchElementException(); c--; if (mustReturnNull) { mustReturnNull = false; last = n; return (0); } final double[][] key = DoubleOpenHashBigSet.this.key; for (;;) { if (displ == 0 && base <= 0) { // We are just enumerating elements from the wrapped list. last = Long.MIN_VALUE; return wrapped.getDouble(-(--base) - 1); } if (displ-- == 0) displ = key[--base].length - 1; final double k = key[base][displ]; if (!(Double.doubleToLongBits(k) == 0)) { last = base * (long)BigArrays.SEGMENT_SIZE + displ; 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. */ private final void shiftKeys(long pos) { // Shift entries with the same hash. long last, slot; double curr; final double[][] key = DoubleOpenHashBigSet.this.key; for (;;) { pos = ((last = pos) + 1) & mask; for (;;) { if ((Double.doubleToLongBits(curr = BigArrays.get(key, pos)) == 0)) { set(key, last, (0)); return; } slot = it.unimi.dsi.fastutil.HashCommon.mix(Double.doubleToRawLongBits(curr)) & mask; if (last <= pos ? last >= slot || slot > pos : last >= slot && slot > pos) break; pos = (pos + 1) & mask; } if (pos < last) { // Wrapped entry. if (wrapped == null) wrapped = new DoubleArrayList(); wrapped.add(BigArrays.get(key, pos)); } set(key, last, curr); } } @Override public void remove() { if (last == -1) throw new IllegalStateException(); if (last == n) DoubleOpenHashBigSet.this.containsNull = false; else if (base >= 0) shiftKeys(last); else { // We're removing wrapped entries. DoubleOpenHashBigSet.this.remove(wrapped.getDouble(-base - 1)); last = -1; // Note that we must not decrement size return; } size--; last = -1; // You can no longer remove this entry. if (ASSERTS) checkTable(); } } @Override public DoubleIterator iterator() { return new SetIterator(); } private class SetSpliterator implements DoubleSpliterator { /* For the sake of keeping things at least somewhat simple * (aka. my sanity), the spliterator will NOT handle the indexing * of the subarrays directly, like iterator does. Instead, it will * delegate to BigArrays and have only a single, unified index it * will fence on. This is probably less effecient, but it avoids having * to track what it means to split on two sets of indexes. * This may change in the future if the performance hit high. */ private static final int POST_SPLIT_CHARACTERISTICS = DoubleSpliterators.SET_SPLITERATOR_CHARACTERISTICS & ~java.util.Spliterator.SIZED; /** The index (which bucket) of the next item to give to the action. */ long pos = 0; /** The maximum bucket (exclusive) to iterate to */ long max = n; /** An upwards counter counting how many we have given */ long c = 0; /** A boolean telling us whether we should return the null key. */ boolean mustReturnNull = DoubleOpenHashBigSet.this.containsNull; boolean hasSplit = false; SetSpliterator() { } SetSpliterator(long pos, long max, boolean mustReturnNull, boolean hasSplit) { this.pos = pos; this.max = max; this.mustReturnNull = mustReturnNull; this.hasSplit = hasSplit; } @Override public boolean tryAdvance(final java.util.function.DoubleConsumer action) { if (mustReturnNull) { mustReturnNull = false; ++c; action.accept((0)); return true; } final double key[][] = DoubleOpenHashBigSet.this.key; while (pos < max) { double gotten = BigArrays.get(key, pos); if (!(Double.doubleToLongBits(gotten) == 0)) { ++c; ++pos; action.accept(gotten); return true; } else { ++pos; } } return false; } @Override public void forEachRemaining(final java.util.function.DoubleConsumer action) { if (mustReturnNull) { mustReturnNull = false; action.accept((0)); ++c; } final double key[][] = DoubleOpenHashBigSet.this.key; while (pos < max) { double gotten = BigArrays.get(key, pos); if (!(Double.doubleToLongBits(gotten) == 0)) { action.accept(gotten); ++c; } ++pos; } } @Override public int characteristics() { return hasSplit ? POST_SPLIT_CHARACTERISTICS : DoubleSpliterators.SET_SPLITERATOR_CHARACTERISTICS; } @Override public long estimateSize() { if (!hasSplit) { // Root spliterator; we know how many are remaining. return size - c; } else { // After we split, we can no longer know exactly how many we have (or at least not efficiently). // (size / n) * (max - pos) aka currentTableDensity * numberOfBucketsLeft seems like a good // estimate. return Math.min(size - c, (long)(((double)realSize() / n) * (max - pos)) + (mustReturnNull ? 1 : 0)); } } @Override public SetSpliterator trySplit() { if (pos >= max - 1) return null; long retLen = (max - pos) >> 1; if (retLen <= 1) return null; long myNewPos = pos + retLen; // Align to an outer array boundary if possible // We add/subtract one to the bounds to ensure the new pos will always shrink the range myNewPos = BigArrays.nearestSegmentStart(myNewPos, pos + 1, max - 1); long retPos = pos; long retMax = myNewPos; // Since null is returned first, and the convention is that the returned split is the prefix of // elements, // the split will take care of returning null (if needed), and we won't return it anymore. SetSpliterator split = new SetSpliterator(retPos, retMax, mustReturnNull, true); this.pos = myNewPos; this.mustReturnNull = false; this.hasSplit = true; return split; } @Override public long skip(long n) { if (n < 0) throw new IllegalArgumentException("Argument must be nonnegative: " + n); if (n == 0) return 0; long skipped = 0; if (mustReturnNull) { mustReturnNull = false; ++skipped; --n; } final double key[][] = DoubleOpenHashBigSet.this.key; while (pos < max && n > 0) { if (!(Double.doubleToLongBits(BigArrays.get(key, pos++)) == 0)) { ++skipped; --n; } } return skipped; } } @Override public DoubleSpliterator spliterator() { return new SetSpliterator(); } @Override public void forEach(final java.util.function.DoubleConsumer action) { if (containsNull) { action.accept((0)); } long pos = 0; final long max = n; final double key[][] = this.key; while (pos < max) { double gotten = BigArrays.get(key, pos++); if (!(Double.doubleToLongBits(gotten) == 0)) { action.accept(gotten); } } } /** * Rehashes this set, 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 set. * @see #trim(long) */ public boolean trim() { return trim(size); } /** * Rehashes this set if the table is too large. * *

* Let N be the smallest table size that can hold max(n,{@link #size64()}) * 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 set in a table of size * N. * *

* This method is useful when reusing sets. {@linkplain #clear() Clearing a set} leaves the table * size untouched. If you are reusing a set 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 sets. * * @param n the threshold for the trimming. * @return true if there was enough memory to trim the set. * @see #trim() */ public boolean trim(final long n) { final long l = bigArraySize(n, f); if (l >= this.n || size > maxFill(l, f)) return true; try { rehash(l); } catch (OutOfMemoryError cantDoIt) { return false; } return true; } /** * Resizes the set. * *

* 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 */ protected void rehash(final long newN) { final double key[][] = this.key; final double newKey[][] = DoubleBigArrays.newBigArray(newN); final long mask = newN - 1; // Note that this is used by the hashing macro final int newSegmentMask = newKey[0].length - 1; final int newBaseMask = newKey.length - 1; int base = 0, displ = 0, b, d; long h; double k; for (long i = realSize(); i-- != 0;) { while ((Double.doubleToLongBits(key[base][displ]) == 0)) base = (base + ((displ = (displ + 1) & segmentMask) == 0 ? 1 : 0)); k = key[base][displ]; h = it.unimi.dsi.fastutil.HashCommon.mix(Double.doubleToRawLongBits(k)); // The starting point. if (!(Double.doubleToLongBits(newKey[b = (int)((h & mask) >>> BigArrays.SEGMENT_SHIFT)][d = (int)(h & newSegmentMask)]) == 0)) while (!(Double.doubleToLongBits(newKey[b = (b + ((d = (d + 1) & newSegmentMask) == 0 ? 1 : 0)) & newBaseMask][d]) == 0)); newKey[b][d] = k; base = (base + ((displ = (displ + 1) & segmentMask) == 0 ? 1 : 0)); } this.n = newN; this.key = newKey; initMasks(); maxFill = maxFill(n, f); } @Deprecated @Override public int size() { return (int)Math.min(Integer.MAX_VALUE, size); } @Override public long size64() { return size; } @Override public boolean isEmpty() { return size == 0; } /** * Returns a deep copy of this big set. * *

* This method performs a deep copy of this big hash set; the data stored in the set, however, is * not cloned. Note that this makes a difference only for object keys. * * @return a deep copy of this big set. */ @Override public DoubleOpenHashBigSet clone() { DoubleOpenHashBigSet c; try { c = (DoubleOpenHashBigSet)super.clone(); } catch (CloneNotSupportedException cantHappen) { throw new InternalError(); } c.key = copy(key); c.containsNull = containsNull; return c; } /** * Returns a hash code for this set. * * This method overrides the generic method provided by the superclass. Since {@code 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. */ @Override public int hashCode() { final double key[][] = this.key; int h = 0, base = 0, displ = 0; for (long j = realSize(); j-- != 0;) { while ((Double.doubleToLongBits(key[base][displ]) == 0)) base = (base + ((displ = (displ + 1) & segmentMask) == 0 ? 1 : 0)); h += it.unimi.dsi.fastutil.HashCommon.double2int(key[base][displ]); base = (base + ((displ = (displ + 1) & segmentMask) == 0 ? 1 : 0)); } return h; } private void writeObject(java.io.ObjectOutputStream s) throws java.io.IOException { final DoubleIterator i = iterator(); s.defaultWriteObject(); for (long j = size; j-- != 0;) s.writeDouble(i.nextDouble()); } private void readObject(java.io.ObjectInputStream s) throws java.io.IOException, ClassNotFoundException { s.defaultReadObject(); n = bigArraySize(size, f); maxFill = maxFill(n, f); final double[][] key = this.key = DoubleBigArrays.newBigArray(n); initMasks(); long h; double k; int base, displ; for (long i = size; i-- != 0;) { k = s.readDouble(); if ((Double.doubleToLongBits(k) == 0)) containsNull = true; else { h = it.unimi.dsi.fastutil.HashCommon.mix(Double.doubleToRawLongBits(k)); if (!(Double.doubleToLongBits(key[base = (int)((h & mask) >>> BigArrays.SEGMENT_SHIFT)][displ = (int)(h & segmentMask)]) == 0)) while (!(Double.doubleToLongBits(key[base = (base + ((displ = (displ + 1) & segmentMask) == 0 ? 1 : 0)) & baseMask][displ]) == 0)); key[base][displ] = k; } } if (ASSERTS) checkTable(); } private void checkTable() { } }





© 2015 - 2024 Weber Informatics LLC | Privacy Policy