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High Performance Primitive Collections: data structures (maps, sets, lists, stacks, queues) generated for combinations of object and primitive types to conserve JVM memory and speed up execution.

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package com.carrotsearch.hppc;

import java.util.*;

import com.carrotsearch.hppc.cursors.*;
import com.carrotsearch.hppc.predicates.*;
import com.carrotsearch.hppc.procedures.*;

import static com.carrotsearch.hppc.HashContainers.*;
import static com.carrotsearch.hppc.Containers.*;

/**
 * A hash map of short to short, implemented using open
 * addressing with linear probing for collision resolution.
 * 
 * 

Note: read about important differences * between hash and scatter sets.

* * @see ShortShortScatterMap * @see HPPC interfaces diagram */ @com.carrotsearch.hppc.Generated( date = "2018-05-21T12:24:06+0200", value = "KTypeVTypeHashMap.java") public class ShortShortHashMap implements ShortShortMap, Preallocable, Cloneable { /** * The array holding keys. */ public short [] keys; /** * The array holding values. */ public short [] values; /** * We perturb hash values with a container-unique * seed to avoid problems with nearly-sorted-by-hash * values on iterations. * * @see #hashKey * @see "http://issues.carrot2.org/browse/HPPC-80" * @see "http://issues.carrot2.org/browse/HPPC-103" */ protected int keyMixer; /** * The number of stored keys (assigned key slots), excluding the special * "empty" key, if any (use {@link #size()} instead). * * @see #size() */ protected int assigned; /** * Mask for slot scans in {@link #keys}. */ protected int mask; /** * Expand (rehash) {@link #keys} when {@link #assigned} hits this value. */ protected int resizeAt; /** * Special treatment for the "empty slot" key marker. */ protected boolean hasEmptyKey; /** * The load factor for {@link #keys}. */ protected double loadFactor; /** * Per-instance hash order mixing strategy. * @see #keyMixer */ protected HashOrderMixingStrategy orderMixer; /** * New instance with sane defaults. */ public ShortShortHashMap() { this(DEFAULT_EXPECTED_ELEMENTS); } /** * New instance with sane defaults. * * @param expectedElements * The expected number of elements guaranteed not to cause buffer * expansion (inclusive). */ public ShortShortHashMap(int expectedElements) { this(expectedElements, DEFAULT_LOAD_FACTOR); } /** * New instance with sane defaults. * * @param expectedElements * The expected number of elements guaranteed not to cause buffer * expansion (inclusive). * @param loadFactor * The load factor for internal buffers. Insane load factors (zero, full capacity) * are rejected by {@link #verifyLoadFactor(double)}. */ public ShortShortHashMap(int expectedElements, double loadFactor) { this(expectedElements, loadFactor, HashOrderMixing.defaultStrategy()); } /** * New instance with the provided defaults. * * @param expectedElements * The expected number of elements guaranteed not to cause a rehash (inclusive). * @param loadFactor * The load factor for internal buffers. Insane load factors (zero, full capacity) * are rejected by {@link #verifyLoadFactor(double)}. * @param orderMixer * Hash key order mixing strategy. See {@link HashOrderMixing} for predefined * implementations. Use constant mixers only if you understand the potential * consequences. */ public ShortShortHashMap(int expectedElements, double loadFactor, HashOrderMixingStrategy orderMixer) { this.orderMixer = orderMixer; this.loadFactor = verifyLoadFactor(loadFactor); ensureCapacity(expectedElements); } /** * Create a hash map from all key-value pairs of another container. */ public ShortShortHashMap(ShortShortAssociativeContainer container) { this(container.size()); putAll(container); } /** * {@inheritDoc} */ @Override public short put(short key, short value) { assert assigned < mask + 1; final int mask = this.mask; if (((key) == 0)) { hasEmptyKey = true; short previousValue = values[mask + 1]; values[mask + 1] = value; return previousValue; } else { final short[] keys = this.keys; int slot = hashKey(key) & mask; short existing; while (!((existing = keys[slot]) == 0)) { if (((existing) == ( key))) { final short previousValue = values[slot]; values[slot] = value; return previousValue; } slot = (slot + 1) & mask; } if (assigned == resizeAt) { allocateThenInsertThenRehash(slot, key, value); } else { keys[slot] = key; values[slot] = value; } assigned++; return ((short) 0); } } /** * {@inheritDoc} */ @Override public int putAll(ShortShortAssociativeContainer container) { final int count = size(); for (ShortShortCursor c : container) { put(c.key, c.value); } return size() - count; } /** * Puts all key/value pairs from a given iterable into this map. */ @Override public int putAll(Iterable iterable){ final int count = size(); for (ShortShortCursor c : iterable) { put(c.key, c.value); } return size() - count; } /** * Trove-inspired API method. An equivalent * of the following code: *
   * if (!map.containsKey(key)) map.put(value);
   * 
* * @param key The key of the value to check. * @param value The value to put if key does not exist. * @return true if key did not exist and value * was placed in the map. */ public boolean putIfAbsent(short key, short value) { int keyIndex = indexOf(key); if (!indexExists(keyIndex)) { indexInsert(keyIndex, key, value); return true; } else { return false; } } /** * If key exists, putValue is inserted into the map, * otherwise any existing value is incremented by additionValue. * * @param key * The key of the value to adjust. * @param putValue * The value to put if key does not exist. * @param incrementValue * The value to add to the existing value if key exists. * @return Returns the current value associated with key (after * changes). */ @Override public short putOrAdd(short key, short putValue, short incrementValue) { assert assigned < mask + 1; int keyIndex = indexOf(key); if (indexExists(keyIndex)) { putValue = ((short) (( values[keyIndex]) + (incrementValue))); indexReplace(keyIndex, putValue); } else { indexInsert(keyIndex, key, putValue); } return putValue; } /** * Adds incrementValue to any existing value for the given key * or inserts incrementValue if key did not previously exist. * * @param key The key of the value to adjust. * @param incrementValue The value to put or add to the existing value if key exists. * @return Returns the current value associated with key (after changes). */ @Override public short addTo(short key, short incrementValue) { return putOrAdd(key, incrementValue, incrementValue); } /** * {@inheritDoc} */ @Override public short remove(short key) { final int mask = this.mask; if (((key) == 0)) { hasEmptyKey = false; short previousValue = values[mask + 1]; values[mask + 1] = ((short) 0); return previousValue; } else { final short[] keys = this.keys; int slot = hashKey(key) & mask; short existing; while (!((existing = keys[slot]) == 0)) { if (((existing) == ( key))) { final short previousValue = values[slot]; shiftConflictingKeys(slot); return previousValue; } slot = (slot + 1) & mask; } return ((short) 0); } } /** * {@inheritDoc} */ @Override public int removeAll(ShortContainer other) { final int before = size(); // Try to iterate over the smaller set of values or // over the container that isn't implementing // efficient contains() lookup. if (other.size() >= size() && other instanceof ShortLookupContainer) { if (hasEmptyKey) { if (other.contains(((short) 0))) { hasEmptyKey = false; values[mask + 1] = ((short) 0); } } final short[] keys = this.keys; for (int slot = 0, max = this.mask; slot <= max;) { short existing; if (!((existing = keys[slot]) == 0) && other.contains(existing)) { // Shift, do not increment slot. shiftConflictingKeys(slot); } else { slot++; } } } else { for (ShortCursor c : other) { this.remove( c.value); } } return before - size(); } /** * {@inheritDoc} */ @Override public int removeAll(ShortShortPredicate predicate) { final int before = size(); final int mask = this.mask; if (hasEmptyKey) { if (predicate.apply(((short) 0), values[mask + 1])) { hasEmptyKey = false; values[mask + 1] = ((short) 0); } } final short[] keys = this.keys; final short[] values = this.values; for (int slot = 0; slot <= mask;) { short existing; if (!((existing = keys[slot]) == 0) && predicate.apply(existing, values[slot])) { // Shift, do not increment slot. shiftConflictingKeys(slot); } else { slot++; } } return before - size(); } /** * {@inheritDoc} */ @Override public int removeAll(ShortPredicate predicate) { final int before = size(); if (hasEmptyKey) { if (predicate.apply(((short) 0))) { hasEmptyKey = false; values[mask + 1] = ((short) 0); } } final short[] keys = this.keys; for (int slot = 0, max = this.mask; slot <= max;) { short existing; if (!((existing = keys[slot]) == 0) && predicate.apply(existing)) { // Shift, do not increment slot. shiftConflictingKeys(slot); } else { slot++; } } return before - size(); } /** * {@inheritDoc} */ @Override public short get(short key) { if (((key) == 0)) { return hasEmptyKey ? values[mask + 1] : ((short) 0); } else { final short[] keys = this.keys; final int mask = this.mask; int slot = hashKey(key) & mask; short existing; while (!((existing = keys[slot]) == 0)) { if (((existing) == ( key))) { return values[slot]; } slot = (slot + 1) & mask; } return ((short) 0); } } /** * {@inheritDoc} */ @Override public short getOrDefault(short key, short defaultValue) { if (((key) == 0)) { return hasEmptyKey ? values[mask + 1] : defaultValue; } else { final short[] keys = this.keys; final int mask = this.mask; int slot = hashKey(key) & mask; short existing; while (!((existing = keys[slot]) == 0)) { if (((existing) == ( key))) { return values[slot]; } slot = (slot + 1) & mask; } return defaultValue; } } /** * {@inheritDoc} */ @Override public boolean containsKey(short key) { if (((key) == 0)) { return hasEmptyKey; } else { final short[] keys = this.keys; final int mask = this.mask; int slot = hashKey(key) & mask; short existing; while (!((existing = keys[slot]) == 0)) { if (((existing) == ( key))) { return true; } slot = (slot + 1) & mask; } return false; } } /** * {@inheritDoc} */ @Override public int indexOf(short key) { final int mask = this.mask; if (((key) == 0)) { return hasEmptyKey ? mask + 1 : ~(mask + 1); } else { final short[] keys = this.keys; int slot = hashKey(key) & mask; short existing; while (!((existing = keys[slot]) == 0)) { if (((existing) == ( key))) { return slot; } slot = (slot + 1) & mask; } return ~slot; } } /** * {@inheritDoc} */ @Override public boolean indexExists(int index) { assert index < 0 || (index >= 0 && index <= mask) || (index == mask + 1 && hasEmptyKey); return index >= 0; } /** * {@inheritDoc} */ @Override public short indexGet(int index) { assert index >= 0 : "The index must point at an existing key."; assert index <= mask || (index == mask + 1 && hasEmptyKey); return values[index]; } /** * {@inheritDoc} */ @Override public short indexReplace(int index, short newValue) { assert index >= 0 : "The index must point at an existing key."; assert index <= mask || (index == mask + 1 && hasEmptyKey); short previousValue = values[index]; values[index] = newValue; return previousValue; } /** * {@inheritDoc} */ @Override public void indexInsert(int index, short key, short value) { assert index < 0 : "The index must not point at an existing key."; index = ~index; if (((key) == 0)) { assert index == mask + 1; values[index] = value; hasEmptyKey = true; } else { assert ((keys[index]) == 0); if (assigned == resizeAt) { allocateThenInsertThenRehash(index, key, value); } else { keys[index] = key; values[index] = value; } assigned++; } } /** * {@inheritDoc} */ @Override public void clear() { assigned = 0; hasEmptyKey = false; Arrays.fill(keys, ((short) 0)); /* */ } /** * {@inheritDoc} */ @Override public void release() { assigned = 0; hasEmptyKey = false; keys = null; values = null; ensureCapacity(Containers.DEFAULT_EXPECTED_ELEMENTS); } /** * {@inheritDoc} */ @Override public int size() { return assigned + (hasEmptyKey ? 1 : 0); } /** * {@inheritDoc} */ public boolean isEmpty() { return size() == 0; } /** * {@inheritDoc} */ @Override public int hashCode() { int h = hasEmptyKey ? 0xDEADBEEF : 0; for (ShortShortCursor c : this) { h += BitMixer.mix(c.key) + BitMixer.mix(c.value); } return h; } /** * {@inheritDoc} */ @Override public boolean equals(Object obj) { return obj != null && getClass() == obj.getClass() && equalElements(getClass().cast(obj)); } /** * Return true if all keys of some other container exist in this container. */ protected boolean equalElements(ShortShortHashMap other) { if (other.size() != size()) { return false; } for (ShortShortCursor c : other) { short key = c.key; if (!containsKey(key) || !((get(key)) == (c.value))) { return false; } } return true; } /** * Ensure this container can hold at least the * given number of keys (entries) without resizing its buffers. * * @param expectedElements The total number of keys, inclusive. */ @Override public void ensureCapacity(int expectedElements) { if (expectedElements > resizeAt || keys == null) { final short[] prevKeys = this.keys; final short[] prevValues = this.values; allocateBuffers(minBufferSize(expectedElements, loadFactor)); if (prevKeys != null && !isEmpty()) { rehash(prevKeys, prevValues); } } } /** * An iterator implementation for {@link #iterator}. */ private final class EntryIterator extends AbstractIterator { private final ShortShortCursor cursor; private final int max = mask + 1; private int slot = -1; public EntryIterator() { cursor = new ShortShortCursor(); } @Override protected ShortShortCursor fetch() { if (slot < max) { short existing; for (slot++; slot < max; slot++) { if (!((existing = keys[slot]) == 0)) { cursor.index = slot; cursor.key = existing; cursor.value = values[slot]; return cursor; } } } if (slot == max && hasEmptyKey) { cursor.index = slot; cursor.key = ((short) 0); cursor.value = values[max]; slot++; return cursor; } return done(); } } /** * {@inheritDoc} */ @Override public Iterator iterator() { return new EntryIterator(); } /** * {@inheritDoc} */ @Override public T forEach(T procedure) { final short[] keys = this.keys; final short[] values = this.values; if (hasEmptyKey) { procedure.apply(((short) 0), values[mask + 1]); } for (int slot = 0, max = this.mask; slot <= max; slot++) { if (!((keys[slot]) == 0)) { procedure.apply(keys[slot], values[slot]); } } return procedure; } /** * {@inheritDoc} */ @Override public T forEach(T predicate) { final short[] keys = this.keys; final short[] values = this.values; if (hasEmptyKey) { if (!predicate.apply(((short) 0), values[mask + 1])) { return predicate; } } for (int slot = 0, max = this.mask; slot <= max; slot++) { if (!((keys[slot]) == 0)) { if (!predicate.apply(keys[slot], values[slot])) { break; } } } return predicate; } /** * Returns a specialized view of the keys of this associated container. The * view additionally implements {@link ObjectLookupContainer}. */ public KeysContainer keys() { return new KeysContainer(); } /** * A view of the keys inside this hash map. */ public final class KeysContainer extends AbstractShortCollection implements ShortLookupContainer { private final ShortShortHashMap owner = ShortShortHashMap.this; @Override public boolean contains(short e) { return owner.containsKey(e); } @Override public T forEach(final T procedure) { owner.forEach(new ShortShortProcedure() { @Override public void apply(short key, short value) { procedure.apply(key); } }); return procedure; } @Override public T forEach(final T predicate) { owner.forEach(new ShortShortPredicate() { @Override public boolean apply(short key, short value) { return predicate.apply(key); } }); return predicate; } @Override public boolean isEmpty() { return owner.isEmpty(); } @Override public Iterator iterator() { return new KeysIterator(); } @Override public int size() { return owner.size(); } @Override public void clear() { owner.clear(); } @Override public void release() { owner.release(); } @Override public int removeAll(ShortPredicate predicate) { return owner.removeAll(predicate); } @Override public int removeAll(final short e) { final boolean hasKey = owner.containsKey(e); if (hasKey) { owner.remove(e); return 1; } else { return 0; } } }; /** * An iterator over the set of assigned keys. */ private final class KeysIterator extends AbstractIterator { private final ShortCursor cursor; private final int max = mask + 1; private int slot = -1; public KeysIterator() { cursor = new ShortCursor(); } @Override protected ShortCursor fetch() { if (slot < max) { short existing; for (slot++; slot < max; slot++) { if (!((existing = keys[slot]) == 0)) { cursor.index = slot; cursor.value = existing; return cursor; } } } if (slot == max && hasEmptyKey) { cursor.index = slot; cursor.value = ((short) 0); slot++; return cursor; } return done(); } } /** * @return Returns a container with all values stored in this map. */ @Override public ShortCollection values() { return new ValuesContainer(); } /** * A view over the set of values of this map. */ private final class ValuesContainer extends AbstractShortCollection { private final ShortShortHashMap owner = ShortShortHashMap.this; @Override public int size() { return owner.size(); } @Override public boolean isEmpty() { return owner.isEmpty(); } @Override public boolean contains(short value) { for (ShortShortCursor c : owner) { if (((c.value) == (value))) { return true; } } return false; } @Override public T forEach(T procedure) { for (ShortShortCursor c : owner) { procedure.apply(c.value); } return procedure; } @Override public T forEach(T predicate) { for (ShortShortCursor c : owner) { if (!predicate.apply(c.value)) { break; } } return predicate; } @Override public Iterator iterator() { return new ValuesIterator(); } @Override public int removeAll(final short e) { return owner.removeAll(new ShortShortPredicate() { @Override public boolean apply(short key, short value) { return ((value) == (e)); } }); } @Override public int removeAll(final ShortPredicate predicate) { return owner.removeAll(new ShortShortPredicate() { @Override public boolean apply(short key, short value) { return predicate.apply(value); } }); } @Override public void clear() { owner.clear(); } @Override public void release() { owner.release(); } } /** * An iterator over the set of assigned values. */ private final class ValuesIterator extends AbstractIterator { private final ShortCursor cursor; private final int max = mask + 1; private int slot = -1; public ValuesIterator() { cursor = new ShortCursor(); } @Override protected ShortCursor fetch() { if (slot < max) { for (slot++; slot < max; slot++) { if (!(( keys[slot]) == 0)) { cursor.index = slot; cursor.value = values[slot]; return cursor; } } } if (slot == max && hasEmptyKey) { cursor.index = slot; cursor.value = values[max]; slot++; return cursor; } return done(); } } /** * {@inheritDoc} */ @Override public ShortShortHashMap clone() { try { /* */ ShortShortHashMap cloned = (ShortShortHashMap) super.clone(); cloned.keys = keys.clone(); cloned.values = values.clone(); cloned.hasEmptyKey = cloned.hasEmptyKey; cloned.orderMixer = orderMixer.clone(); return cloned; } catch (CloneNotSupportedException e) { throw new RuntimeException(e); } } /** * Convert the contents of this map to a human-friendly string. */ @Override public String toString() { final StringBuilder buffer = new StringBuilder(); buffer.append("["); boolean first = true; for (ShortShortCursor cursor : this) { if (!first) { buffer.append(", "); } buffer.append(cursor.key); buffer.append("=>"); buffer.append(cursor.value); first = false; } buffer.append("]"); return buffer.toString(); } @Override public String visualizeKeyDistribution(int characters) { return ShortBufferVisualizer.visualizeKeyDistribution(keys, mask, characters); } /** * Creates a hash map from two index-aligned arrays of key-value pairs. */ public static ShortShortHashMap from(short[] keys, short[] values) { if (keys.length != values.length) { throw new IllegalArgumentException("Arrays of keys and values must have an identical length."); } ShortShortHashMap map = new ShortShortHashMap(keys.length); for (int i = 0; i < keys.length; i++) { map.put(keys[i], values[i]); } return map; } /** * Returns a hash code for the given key. * *

The default implementation mixes the hash of the key with {@link #keyMixer} * to differentiate hash order of keys between hash containers. Helps * alleviate problems resulting from linear conflict resolution in open * addressing.

* *

The output from this function should evenly distribute keys across the * entire integer range.

*/ protected int hashKey(short key) { assert !((key) == 0); // Handled as a special case (empty slot marker). return BitMixer.mix(key, this.keyMixer); } /** * Validate load factor range and return it. Override and suppress if you need * insane load factors. */ protected double verifyLoadFactor(double loadFactor) { checkLoadFactor(loadFactor, MIN_LOAD_FACTOR, MAX_LOAD_FACTOR); return loadFactor; } /** * Rehash from old buffers to new buffers. */ protected void rehash(short[] fromKeys, short[] fromValues) { assert fromKeys.length == fromValues.length && HashContainers.checkPowerOfTwo(fromKeys.length - 1); // Rehash all stored key/value pairs into the new buffers. final short[] keys = this.keys; final short[] values = this.values; final int mask = this.mask; short existing; // Copy the zero element's slot, then rehash everything else. int from = fromKeys.length - 1; keys[keys.length - 1] = fromKeys[from]; values[values.length - 1] = fromValues[from]; while (--from >= 0) { if (!((existing = fromKeys[from]) == 0)) { int slot = hashKey(existing) & mask; while (!((keys[slot]) == 0)) { slot = (slot + 1) & mask; } keys[slot] = existing; values[slot] = fromValues[from]; } } } /** * Allocate new internal buffers. This method attempts to allocate * and assign internal buffers atomically (either allocations succeed or not). */ protected void allocateBuffers(int arraySize) { assert Integer.bitCount(arraySize) == 1; // Compute new hash mixer candidate before expanding. final int newKeyMixer = this.orderMixer.newKeyMixer(arraySize); // Ensure no change is done if we hit an OOM. short[] prevKeys = this.keys; short[] prevValues = this.values; try { int emptyElementSlot = 1; this.keys = (new short [arraySize + emptyElementSlot]); this.values = (new short [arraySize + emptyElementSlot]); } catch (OutOfMemoryError e) { this.keys = prevKeys; this.values = prevValues; throw new BufferAllocationException( "Not enough memory to allocate buffers for rehashing: %,d -> %,d", e, this.mask + 1, arraySize); } this.resizeAt = expandAtCount(arraySize, loadFactor); this.keyMixer = newKeyMixer; this.mask = arraySize - 1; } /** * This method is invoked when there is a new key/ value pair to be inserted into * the buffers but there is not enough empty slots to do so. * * New buffers are allocated. If this succeeds, we know we can proceed * with rehashing so we assign the pending element to the previous buffer * (possibly violating the invariant of having at least one empty slot) * and rehash all keys, substituting new buffers at the end. */ protected void allocateThenInsertThenRehash(int slot, short pendingKey, short pendingValue) { assert assigned == resizeAt && (( keys[slot]) == 0) && !((pendingKey) == 0); // Try to allocate new buffers first. If we OOM, we leave in a consistent state. final short[] prevKeys = this.keys; final short[] prevValues = this.values; allocateBuffers(nextBufferSize(mask + 1, size(), loadFactor)); assert this.keys.length > prevKeys.length; // We have succeeded at allocating new data so insert the pending key/value at // the free slot in the old arrays before rehashing. prevKeys[slot] = pendingKey; prevValues[slot] = pendingValue; // Rehash old keys, including the pending key. rehash(prevKeys, prevValues); } /** * Shift all the slot-conflicting keys and values allocated to * (and including) slot. */ protected void shiftConflictingKeys(int gapSlot) { final short[] keys = this.keys; final short[] values = this.values; final int mask = this.mask; // Perform shifts of conflicting keys to fill in the gap. int distance = 0; while (true) { final int slot = (gapSlot + (++distance)) & mask; final short existing = keys[slot]; if (((existing) == 0)) { break; } final int idealSlot = hashKey(existing); final int shift = (slot - idealSlot) & mask; if (shift >= distance) { // Entry at this position was originally at or before the gap slot. // Move the conflict-shifted entry to the gap's position and repeat the procedure // for any entries to the right of the current position, treating it // as the new gap. keys[gapSlot] = existing; values[gapSlot] = values[slot]; gapSlot = slot; distance = 0; } } // Mark the last found gap slot without a conflict as empty. keys[gapSlot] = ((short) 0); values[gapSlot] = ((short) 0); assigned--; } }




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