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High Performance Primitive Collections Realtime
(fork of HPPC from Carrotsearch)
Fundamental data structures (maps, sets, lists, queues, heaps, sorts) generated for
combinations of object and primitive types to conserve JVM memory and speed
up execution. The Realtime fork intends to extend the existing collections, by tweaking to remove any dynamic allocations at runtime,
and to obtain low variance execution times whatever the input nature.
The newest version!
package com.carrotsearch.hppcrt.maps;
import com.carrotsearch.hppcrt.*;
import com.carrotsearch.hppcrt.cursors.*;
import com.carrotsearch.hppcrt.predicates.*;
import com.carrotsearch.hppcrt.procedures.*;
import com.carrotsearch.hppcrt.hash.*;
// If RH is defined, RobinHood Hashing is in effect :
/**
* A hash map of Object to short, implemented using open
* addressing with linear probing for collision resolution.
*
* In addition, the hashing strategy can be changed
* by overriding ({@link #equalKeys(Object, Object)} and {@link #hashKey(Object)}) together,
* which then replaces the usual ({@link #equals(Object)} and {@link #hashCode()}) from the keys themselves.
* This is useful to define the equivalence of keys when the user has no control over the keys implementation.
*
*
* The internal buffers of this implementation ({@link #keys}, {@link #values}),
* are always allocated to the nearest size that is a power of two. When
* the capacity exceeds the given load factor, the buffer size is doubled.
*
*
* This implementation supports null keys.
*
* Important note. The implementation uses power-of-two tables and linear
* probing, which may cause poor performance (many collisions) if hash values are
* not properly distributed.
*
*
*
*
*
Robin-Hood hashing algorithm is also used to minimize variance
* in insertion and search-related operations, for an all-around smother operation at the cost
* of smaller peak performance:
* - Pedro Celis (1986) for the original Robin-Hood hashing paper,
* - MoonPolySoft/Cliff Moon for the initial Robin-hood on HPPC implementation,
* - Vincent Sonnier for the present implementation using cached hashes.
*
*/
@javax.annotation.Generated(
date = "2017-07-11T19:16:27+0200",
value = "KTypeVTypeHashMap.java")
public class ObjectShortHashMap
implements ObjectShortMap, Cloneable
{
protected short defaultValue = ((short)0);
/**
* Hash-indexed array holding all keys.
*
* Direct map iteration: iterate {keys[i], values[i]} for i in [0; keys.length[ where keys[i] != 0/null, then also
* {0/null, {@link #allocatedDefaultKeyValue} } is in the map if {@link #allocatedDefaultKey} = true.
*
*/
public
Object[]
keys;
/**
* Hash-indexed array holding all values associated to the keys.
* stored in {@link #keys}.
*/
public short []
values;
/**
* * Caches the hash value = hash(keys[i]) & mask, if keys[i] != 0/null,
* for every index i.
* * @see #assigned
*/
protected int[] hash_cache;
/**
* True if key = 0/null is in the map.
*/
public boolean allocatedDefaultKey = false;
/**
* if allocatedDefaultKey = true, contains the associated V to the key = 0/null
*/
public short allocatedDefaultKeyValue;
/**
* Cached number of assigned slots in {@link #keys}.
*/
protected int assigned;
/**
* The load factor for this map (fraction of allocated slots
* before the buffers must be rehashed or reallocated).
*/
protected final double loadFactor;
/**
* Resize buffers when {@link #keys} hits this value.
*/
private int resizeAt;
/**
* Per-instance size perturbation
* introduced in rehashing to create a unique key distribution.
*/
private final int perturbation = Containers.randomSeed32();
/**
* Override this method, together with {@link #equalKeys(Object, Object)}
* to customize the hashing strategy. Note that this method is guaranteed
* to be called with a non-null key argument.
* By default, this method calls key.{@link #hashCode()}.
* @param key Object to be hashed.
* @return the hashed value of key, following the same semantic
* as {@link #hashCode()};
* @see #hashCode()
* @see #equalKeys(Object, Object)
*/
protected int hashKey(final KType key) {
//default maps on Object.hashCode()
return key.hashCode();
}
/**
* Override this method together with {@link #hashKey(Object)}
* to customize the hashing strategy. Note that this method is guaranteed
* to be called with both non-null arguments.
* By default, this method calls a.{@link #equals(b)}.
* @param a not-null Object to be compared
* @param b not-null Object to be compared
* @return true if a and b are considered equal, following the same
* semantic as {@link #equals(Object)}.
* @see #equals(Object)
* @see #hashKey(Object)
*/
protected boolean equalKeys(final KType a, final KType b) {
//default maps on Object.equals()
return ((a).equals((b)));
}
/**
* Default constructor: Creates a hash map with the default capacity of {@link Containers#DEFAULT_EXPECTED_ELEMENTS},
* load factor of {@link HashContainers#DEFAULT_LOAD_FACTOR}.
*
* See class notes about hash distribution importance.
*/
public ObjectShortHashMap() {
this(Containers.DEFAULT_EXPECTED_ELEMENTS);
}
/**
* Creates a hash map with the given initial capacity, default load factor of
* {@link HashContainers#DEFAULT_LOAD_FACTOR}.
*
* See class notes about hash distribution importance.
*
* @param initialCapacity Initial capacity (greater than zero and automatically
* rounded to the next power of two).
*/
public ObjectShortHashMap(final int initialCapacity) {
this(initialCapacity, HashContainers.DEFAULT_LOAD_FACTOR);
}
/**
* Creates a hash map with the given initial capacity,
* load factor.
*
* @param loadFactor The load factor (greater than zero and smaller than 1).
*/
public ObjectShortHashMap(final int initialCapacity, final double loadFactor) {
this.loadFactor = loadFactor;
//take into account of the load factor to guarantee no reallocations before reaching initialCapacity.
allocateBuffers(HashContainers.minBufferSize(initialCapacity, loadFactor));
}
/**
* Create a hash map from all key-value pairs of another container.
*/
public ObjectShortHashMap(final ObjectShortAssociativeContainer container) {
this(container.size());
putAll(container);
}
/**
* {@inheritDoc}
*/
@Override
public short put(KType key, short value) {
if (((key) == null)) {
if (this.allocatedDefaultKey) {
final short previousValue = this.allocatedDefaultKeyValue;
this.allocatedDefaultKeyValue = value;
return previousValue;
}
this.allocatedDefaultKeyValue = value;
this.allocatedDefaultKey = true;
return this.defaultValue;
}
final int mask = this.keys.length - 1;
final KType[] keys = ((KType[])(this.keys));
int slot = (BitMixer.mix(hashKey((key)) , this.perturbation)) & mask;
KType existing;
final short[] values = ((this.values));
final int[] cached = this.hash_cache;
KType tmpKey;
short tmpValue;
int tmpAllocated;
int initial_slot = slot;
int dist = 0;
int existing_distance = 0;
while (!((existing = keys[slot]) == null)) {
existing_distance = probe_distance(slot, cached);
//When first entering the while loop, then key == original key to search.
//So either:
//1) key is immediately found and the routine bail out,
//or
//2) If the Robin-hood criteria of distance is not met, we search the next slot, (usual linear probing)
//or
//3) else the criteria of distance is met, then (key,value) is swapped with the ones in
//slot position which becomes the new (key,value) to consider. This is OK because keys are swapped only if dist > existing_distance,
//i.e only if the key to add is NOT in the map, see containsKey(). So we steal the rich (a previously entered key, favored because having being inserted
//in a less crowed array) to give to the poor, the now inserted key. Then, we start searching again in the next slot.
// Robin-hood shortcut: if key exists, it can only be found in dist <= existing_distance range.
//indeed we should expect to never see an existing element with a shorter probe count (existing_distance)
//than our current count (dist): if that had happened, there would’ve been a swap during insertion, see below.
//also see containsKey(), get() and remove() for the same trick.
if ( dist <= existing_distance && (equalKeys((key), (existing)))) {
final short oldValue = ((this.values[slot]));
this.values[slot] = value;
return oldValue;
}
//re-shuffle keys to minimize variance
//we actually enter here only if the key to add is NOT in the map.
if (dist > existing_distance) {
//swap current (key, value, initial_slot) with slot places
tmpKey = keys[slot];
keys[slot] = key;
key = tmpKey;
tmpAllocated = cached[slot];
cached[slot] = initial_slot;
initial_slot = tmpAllocated;
tmpValue = values[slot];
values[slot] = value;
value = tmpValue;
dist = existing_distance;
}
slot = (slot + 1) & mask;
dist++;
} //end while
// Check if we need to grow. If so, reallocate new data, fill in the last element
// and rehash.
if (this.assigned == this.resizeAt) {
expandAndPut(key, value, slot);
} else {
this.assigned++;
cached[slot] = initial_slot;
keys[slot] = key;
values[slot] = value;
}
return this.defaultValue;
}
/**
* {@inheritDoc}
*/
@Override
public int putAll(final ObjectShortAssociativeContainer container) {
return putAll((Iterable>) container);
}
/**
* {@inheritDoc}
*/
@Override
public int putAll(final Iterable> iterable) {
final int count = this.size();
for (final ObjectShortCursor c : iterable) {
put(c.key, c.value);
}
return this.size() - count;
}
/**
* {@inheritDoc}
*/
@Override
public boolean putIfAbsent(final KType key, final short value) {
if (!containsKey(key)) {
put(key, value);
return true;
}
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).
*/
@SuppressWarnings("cast")
@Override
public short putOrAdd(final KType key, short putValue, final short incrementValue) {
if (containsKey(key)) {
putValue = get(key);
putValue = (short) (((putValue) + (incrementValue)));
}
put(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(final KType key, final short incrementValue)
{
return putOrAdd(key, incrementValue, incrementValue);
}
/**
* Expand the internal storage buffers (capacity) and rehash.
*/
private void expandAndPut(final KType pendingKey, final short pendingValue, final int freeSlot) {
assert this.assigned == this.resizeAt;
//default sentinel value is never in the keys[] array, so never trigger reallocs
assert !((pendingKey) == null);
// Try to allocate new buffers first. If we OOM, it'll be now without
// leaving the data structure in an inconsistent state.
final KType[] oldKeys = ((KType[])(this.keys));
final short[] oldValues = ((this.values));
allocateBuffers(HashContainers.nextBufferSize(this.keys.length, this.assigned, this.loadFactor));
// We have succeeded at allocating new data so insert the pending key/value at
// the free slot in the old arrays before rehashing.
this.assigned++;
oldKeys[freeSlot] = pendingKey;
oldValues[freeSlot] = pendingValue;
//for inserts
final int mask = this.keys.length - 1;
KType key = (null);
short value = ((short)0);
int slot = -1;
final KType[] keys = ((KType[])(this.keys));
final short[] values = ((this.values));
final int[] cached = this.hash_cache;
KType tmpKey = (null);
short tmpValue = ((short)0);
int tmpAllocated = -1;
int initial_slot = -1;
int dist = -1;
int existing_distance = -1;
//iterate all the old arrays to add in the newly allocated buffers
//It is important to iterate backwards to minimize the conflict chain length !
final int perturb = this.perturbation;
for (int i = oldKeys.length; --i >= 0;) {
//only consider non-empty slots, of course
if (!((key = oldKeys[i]) == null)) {
value = oldValues[i];
slot = (BitMixer.mix(hashKey((key)) , (perturb))) & mask;
initial_slot = slot;
dist = 0;
//similar to put(), except all inserted keys are known to be unique.
while ((!(((keys)[(slot)]) == null))) {
//re-shuffle keys to minimize variance
existing_distance = probe_distance(slot, cached);
if (dist > existing_distance) {
//swap current (key, value, initial_slot) with slot places
tmpKey = keys[slot];
keys[slot] = key;
key = tmpKey;
tmpAllocated = cached[slot];
cached[slot] = initial_slot;
initial_slot = tmpAllocated;
tmpValue = values[slot];
values[slot] = value;
value = tmpValue;
dist = existing_distance;
}
slot = (slot + 1) & mask;
dist++;
} //end while
cached[slot] = initial_slot;
keys[slot] = key;
values[slot] = value;
}
}
}
/**
* Allocate internal buffers for a given capacity.
*
* @param capacity New capacity (must be a power of two).
*/
@SuppressWarnings("boxing")
private void allocateBuffers(final int capacity) {
try {
final KType[] keys = ((KType[])new Object[(capacity)]);
final short[] values = (new short[(capacity)]);
final int[] cached = new int[capacity];
this.keys = keys;
this.values = values;
this.hash_cache = cached;
//allocate so that there is at least one slot that remains allocated = false
//this is compulsory to guarantee proper stop in searching loops
this.resizeAt = HashContainers.expandAtCount(capacity, this.loadFactor);
} catch (final OutOfMemoryError e) {
throw new BufferAllocationException(
"Not enough memory to allocate buffers to grow from %d -> %d elements",
e,
(this.keys == null) ? 0 : this.keys.length,
capacity);
}
}
/**
* {@inheritDoc}
*/
@Override
public short remove(final KType key) {
if (((key) == null)) {
if (this.allocatedDefaultKey) {
final short previousValue = this.allocatedDefaultKeyValue;
this.allocatedDefaultKey = false;
return previousValue;
}
return this.defaultValue;
}
final int mask = this.keys.length - 1;
final KType[] keys = ((KType[])(this.keys));
int slot = (BitMixer.mix(hashKey((key)) , this.perturbation)) & mask;
KType existing;
int dist = 0;
final int[] cached = this.hash_cache;
while (!((existing = keys[slot]) == null)
&& dist <= probe_distance(slot, cached) ) {
if ((equalKeys((key), (existing)))) {
final short value = ((this.values[slot]));
shiftConflictingKeys(slot);
return value;
}
slot = (slot + 1) & mask;
dist++;
} //end while true
return this.defaultValue;
}
/**
* Shift all the slot-conflicting keys allocated to (and including) slot.
*/
private void shiftConflictingKeys(int gapSlot) {
final int mask = this.keys.length - 1;
final KType[] keys = ((KType[])(this.keys));
final short[] values = ((this.values));
final int[] cached = this.hash_cache;
// Perform shifts of conflicting keys to fill in the gap.
int distance = 0;
while (true) {
final int slot = (gapSlot + (++distance)) & mask;
final KType existing = keys[slot];
final short existingValue = values[slot];
if (((existing) == null)) {
break;
}
//use the cached value, no need to recompute
final int idealSlotModMask = cached[slot];
//original HPPC code: shift = (slot - idealSlot) & mask;
//equivalent to shift = (slot & mask - idealSlot & mask) & mask;
//since slot and idealSlotModMask are already folded, we have :
final int shift = (slot - idealSlotModMask) & 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] = existingValue;
cached[gapSlot] = idealSlotModMask;
gapSlot = slot;
distance = 0;
}
} //end while
// Mark the last found gap slot without a conflict as empty.
keys[gapSlot] = (null);
/* */
this.assigned--;
}
/**
* {@inheritDoc}
*/
@SuppressWarnings("unchecked")
@Override
public int removeAll(final ObjectContainer other) {
final int before = this.size();
//1) other is a ObjectLookupContainer, so with fast lookup guarantees
//and is bigger than this, so take advantage of both and iterate over this
//and test other elements by their contains().
if (other.size() >= before && other instanceof ObjectLookupContainer) {
if (this.allocatedDefaultKey) {
if (other.contains((null))) {
this.allocatedDefaultKey = false;
}
}
final KType[] keys = ((KType[])(this.keys));
for (int i = 0; i < keys.length;) {
KType existing;
if (!((existing = keys[i]) == null) && other.contains(existing)) {
shiftConflictingKeys(i);
// Shift, do not increment slot.
} else {
i++;
}
}
} else {
//2) Do not use contains() from container, which may lead to O(n**2) execution times,
//so it iterate linearly and call remove() from map which is O(1).
for (final ObjectCursor c : other) {
remove(((KType)(c.value)));
}
}
return before - this.size();
}
/**
* {@inheritDoc}
*/
@Override
public int removeAll(final ObjectPredicate predicate) {
final int before = this.size();
if (this.allocatedDefaultKey) {
if (predicate.apply((null))) {
this.allocatedDefaultKey = false;
}
}
final KType[] keys = ((KType[])(this.keys));
for (int i = 0; i < keys.length;) {
KType existing;
if (!((existing = keys[i]) == null) && predicate.apply(existing)) {
shiftConflictingKeys(i);
// Shift, do not increment slot.
} else {
i++;
}
}
return before - this.size();
}
/**
* {@inheritDoc}
*/
@Override
public int removeAll(final ObjectShortPredicate predicate) {
final int before = this.size();
if (this.allocatedDefaultKey) {
if (predicate.apply((null), this.allocatedDefaultKeyValue)) {
this.allocatedDefaultKey = false;
}
}
final KType[] keys = ((KType[])(this.keys));
final short[] values = ((this.values));
for (int i = 0; i < keys.length;) {
KType existing;
if (!((existing = keys[i]) == null) && predicate.apply(existing, values[i])) {
shiftConflictingKeys(i);
// Shift, do not increment slot.
} else {
i++;
}
}
return before - this.size();
}
/**
* {@inheritDoc}
*/
@Override
public short get(final KType key) {
if (((key) == null)) {
if (this.allocatedDefaultKey) {
return this.allocatedDefaultKeyValue;
}
return this.defaultValue;
}
final int mask = this.keys.length - 1;
final KType[] keys = ((KType[])(this.keys));
int slot = (BitMixer.mix(hashKey((key)) , this.perturbation)) & mask;
KType existing;
int dist = 0;
final int[] cached = this.hash_cache;
while (!((existing = keys[slot]) == null)
&& dist <= probe_distance(slot, cached) ) {
if ((equalKeys((key), (existing)))) {
return ((this.values[slot]));
}
slot = (slot + 1) & mask;
dist++;
} //end while true
return this.defaultValue;
}
/**
* {@inheritDoc}
*/
@Override
public boolean containsKey(final KType key) {
if (((key) == null)) {
return this.allocatedDefaultKey;
}
final int mask = this.keys.length - 1;
final KType[] keys = ((KType[])(this.keys));
int slot = (BitMixer.mix(hashKey((key)) , this.perturbation)) & mask;
KType existing;
int dist = 0;
final int[] cached = this.hash_cache;
while (!((existing = keys[slot]) == null)
&& dist <= probe_distance(slot, cached) ) {
if ((equalKeys((key), (existing)))) {
return true;
}
slot = (slot + 1) & mask;
dist++;
} //end while true
return false;
}
/**
* {@inheritDoc}
*/
@Override
public void clear() {
this.assigned = 0;
// States are always cleared.
this.allocatedDefaultKey = false;
//Faster than Arrays.fill(keys, null); // Help the GC.
ObjectArrays.blankArray(this.keys, 0, this.keys.length);
}
/**
* {@inheritDoc}
*/
@Override
public int size() {
return this.assigned + (this.allocatedDefaultKey ? 1 : 0);
}
/**
* {@inheritDoc}
*/
@Override
public int capacity() {
return this.resizeAt;
}
/**
* {@inheritDoc}
*
* Note that an empty container may still contain many deleted keys (that occupy buffer
* space). Adding even a single element to such a container may cause rehashing.
*/
@Override
public boolean isEmpty() {
return size() == 0;
}
/**
* {@inheritDoc}
*/
@Override
public int hashCode() {
int h = 0;
if (this.allocatedDefaultKey) {
h += BitMixer.mix(this.allocatedDefaultKeyValue);
}
final KType[] keys = ((KType[])(this.keys));
final short[] values = ((this.values));
for (int i = keys.length; --i >= 0;) {
KType existing;
if (!((existing = keys[i]) == null)) {
h += BitMixer.mix(existing) ^ BitMixer.mix(values[i]);
}
}
return h;
}
/**
* {@inheritDoc}
*/
@Override
public boolean equals(final Object obj) {
if (obj != null) {
if (obj == this) {
return true;
}
//must be of the same class, subclasses are not comparable
if (obj.getClass() != this.getClass()) {
return false;
}
/* */
@SuppressWarnings("unchecked")
final/* */
ObjectShortHashMap other = (ObjectShortHashMap) obj;
//must be of the same size
if (other.size() != this.size()) {
return false;
}
final EntryIterator it = this.iterator();
while (it.hasNext()) {
final ObjectShortCursor c = it.next();
if (!other.containsKey(c.key)) {
//recycle
it.release();
return false;
}
final short otherValue = other.get(c.key);
if (!((c.value) == (otherValue))) {
//recycle
it.release();
return false;
}
} //end while
return true;
}
return false;
}
/**
* An iterator implementation for {@link #iterator}.
* Holds a ObjectShortCursor returning
* (key, value, index) = (Object key, short value, index the position in keys {@link ObjectShortHashMap#keys}, or keys.length for key = 0/null)
*/
public final class EntryIterator extends AbstractIterator>
{
public final ObjectShortCursor cursor;
public EntryIterator() {
this.cursor = new ObjectShortCursor();
this.cursor.index = -2;
}
/**
* Iterate backwards w.r.t the buffer, to
* minimize collision chains when filling another hash container (ex. with putAll())
*/
@Override
protected ObjectShortCursor fetch() {
if (this.cursor.index == ObjectShortHashMap.this.keys.length + 1) {
if (ObjectShortHashMap.this.allocatedDefaultKey) {
this.cursor.index = ObjectShortHashMap.this.keys.length;
this.cursor.key = (null);
this.cursor.value = ObjectShortHashMap.this.allocatedDefaultKeyValue;
return this.cursor;
}
//no value associated with the default key, continue iteration...
this.cursor.index = ObjectShortHashMap.this.keys.length;
}
int i = this.cursor.index - 1;
while (i >= 0 && !(!(((((KType[])(ObjectShortHashMap.this.keys)))[(i)]) == null))) {
i--;
}
if (i == -1) {
return done();
}
this.cursor.index = i;
this.cursor.key = ((KType)(ObjectShortHashMap.this.keys[i]));
this.cursor.value = ((ObjectShortHashMap.this.values[i]));
return this.cursor;
}
}
/**
* internal pool of EntryIterator
*/
protected final IteratorPool, EntryIterator> entryIteratorPool = new IteratorPool, EntryIterator>(
new ObjectFactory() {
@Override
public EntryIterator create() {
return new EntryIterator();
}
@Override
public void initialize(final EntryIterator obj) {
obj.cursor.index = ObjectShortHashMap.this.keys.length + 1;
}
@Override
public void reset(final EntryIterator obj) {
obj.cursor.key = null;
}
});
/**
* {@inheritDoc}
*/
@Override
public EntryIterator iterator() {
//return new EntryIterator();
return this.entryIteratorPool.borrow();
}
/**
* {@inheritDoc}
*/
@Override
public > T forEach(final T procedure) {
if (this.allocatedDefaultKey) {
procedure.apply((null), this.allocatedDefaultKeyValue);
}
final KType[] keys = ((KType[])(this.keys));
final short[] values = ((this.values));
//Iterate in reverse for side-stepping the longest conflict chain
//in another hash, in case apply() is actually used to fill another hash container.
for (int i = keys.length - 1; i >= 0; i--) {
KType existing;
if (!((existing = keys[i]) == null)) {
procedure.apply(existing, values[i]);
}
}
return procedure;
}
/**
* {@inheritDoc}
*/
@Override
public > T forEach(final T predicate) {
if (this.allocatedDefaultKey) {
if (!predicate.apply((null), this.allocatedDefaultKeyValue)) {
return predicate;
}
}
final KType[] keys = ((KType[])(this.keys));
final short[] values = ((this.values));
//Iterate in reverse for side-stepping the longest conflict chain
//in another hash, in case apply() is actually used to fill another hash container.
for (int i = keys.length - 1; i >= 0; i--) {
KType existing;
if (!((existing = keys[i]) == null)) {
if (!predicate.apply(existing, values[i])) {
break;
}
}
} //end for
return predicate;
}
/**
* {@inheritDoc}
* @return a new KeysCollection view of the keys of this map.
*/
@Override
public KeysCollection keys() {
return new KeysCollection();
}
/**
* A view of the keys inside this map.
*/
public final class KeysCollection extends AbstractObjectCollection implements ObjectLookupContainer
{
private final ObjectShortHashMap owner = ObjectShortHashMap.this;
@Override
public boolean contains(final KType e) {
return containsKey(e);
}
@Override
public > T forEach(final T procedure) {
if (this.owner.allocatedDefaultKey) {
procedure.apply((null));
}
final KType[] keys = ((KType[])(this.owner.keys));
//Iterate in reverse for side-stepping the longest conflict chain
//in another hash, in case apply() is actually used to fill another hash container.
for (int i = keys.length - 1; i >= 0; i--) {
KType existing;
if (!((existing = keys[i]) == null)) {
procedure.apply(existing);
}
}
return procedure;
}
@Override
public > T forEach(final T predicate) {
if (this.owner.allocatedDefaultKey) {
if (!predicate.apply((null))) {
return predicate;
}
}
final KType[] keys = ((KType[])(this.owner.keys));
//Iterate in reverse for side-stepping the longest conflict chain
//in another hash, in case apply() is actually used to fill another hash container.
for (int i = keys.length - 1; i >= 0; i--) {
KType existing;
if (!((existing = keys[i]) == null)) {
if (!predicate.apply(existing)) {
break;
}
}
}
return predicate;
}
/**
* {@inheritDoc}
*/
@Override
public KeysIterator iterator() {
//return new KeysIterator();
return this.keyIteratorPool.borrow();
}
/**
* {@inheritDoc}
*/
@Override
public int size() {
return this.owner.size();
}
/**
* {@inheritDoc}
*/
@Override
public int capacity() {
return this.owner.capacity();
}
@Override
public void clear() {
this.owner.clear();
}
@Override
public int removeAll(final ObjectPredicate predicate) {
return this.owner.removeAll(predicate);
}
@Override
public int removeAll(final KType e) {
final boolean hasKey = this.owner.containsKey(e);
int result = 0;
if (hasKey) {
this.owner.remove(e);
result = 1;
}
return result;
}
/**
* internal pool of KeysIterator
*/
protected final IteratorPool, KeysIterator> keyIteratorPool = new IteratorPool, KeysIterator>(
new ObjectFactory() {
@Override
public KeysIterator create() {
return new KeysIterator();
}
@Override
public void initialize(final KeysIterator obj) {
obj.cursor.index = ObjectShortHashMap.this.keys.length + 1;
}
@Override
public void reset(final KeysIterator obj) {
obj.cursor.value = null;
}
});
@Override
public KType[] toArray(final KType[] target) {
int count = 0;
if (this.owner.allocatedDefaultKey) {
target[count++] = (null);
}
final KType[] keys = ((KType[])(this.owner.keys));
for (int i = 0; i < keys.length; i++) {
KType existing;
if (!((existing = keys[i]) == null)) {
target[count++] = existing;
}
}
assert count == this.owner.size();
return target;
}
};
/**
* An iterator over the set of keys.
* Holds a ObjectCursor returning (value, index) = (Object key, index the position in buffer {@link ObjectShortHashMap#keys}, or keys.length for key = 0/null.)
*/
public final class KeysIterator extends AbstractIterator>
{
public final ObjectCursor cursor;
public KeysIterator() {
this.cursor = new ObjectCursor();
this.cursor.index = -2;
}
/**
* Iterate backwards w.r.t the buffer, to
* minimize collision chains when filling another hash container (ex. with putAll())
*/
@Override
protected ObjectCursor fetch() {
if (this.cursor.index == ObjectShortHashMap.this.keys.length + 1) {
if (ObjectShortHashMap.this.allocatedDefaultKey) {
this.cursor.index = ObjectShortHashMap.this.keys.length;
this.cursor.value = (null);
return this.cursor;
}
//no value associated with the default key, continue iteration...
this.cursor.index = ObjectShortHashMap.this.keys.length;
}
int i = this.cursor.index - 1;
while (i >= 0 && !(!(((((KType[])(ObjectShortHashMap.this.keys)))[(i)]) == null))) {
i--;
}
if (i == -1) {
return done();
}
this.cursor.index = i;
this.cursor.value = ((KType)(ObjectShortHashMap.this.keys[i]));
return this.cursor;
}
}
/**
* {@inheritDoc}
* @return a new ValuesCollection view of the values of this map.
*/
@Override
public ValuesCollection values() {
return new ValuesCollection();
}
/**
* A view over the set of values of this map.
*/
public final class ValuesCollection extends AbstractShortCollection
{
private final ObjectShortHashMap owner = ObjectShortHashMap.this;
/**
* {@inheritDoc}
*/
@Override
public int size() {
return this.owner.size();
}
/**
* {@inheritDoc}
*/
@Override
public int capacity() {
return this.owner.capacity();
}
@Override
public boolean contains(final short value) {
if (this.owner.allocatedDefaultKey && ((value) == (this.owner.allocatedDefaultKeyValue))) {
return true;
}
// This is a linear scan over the values, but it's in the contract, so be it.
final KType[] keys = ((KType[])(this.owner.keys));
final short[] values = ((this.owner.values));
for (int slot = 0; slot < keys.length; slot++) {
if ((!(((keys)[(slot)]) == null)) && ((value) == (values[slot]))) {
return true;
}
}
return false;
}
@Override
public T forEach(final T procedure) {
if (this.owner.allocatedDefaultKey) {
procedure.apply(this.owner.allocatedDefaultKeyValue);
}
final KType[] keys = ((KType[])(this.owner.keys));
final short[] values = ((this.owner.values));
for (int slot = 0; slot < keys.length; slot++) {
if ((!(((keys)[(slot)]) == null))) {
procedure.apply(values[slot]);
}
}
return procedure;
}
@Override
public T forEach(final T predicate) {
if (this.owner.allocatedDefaultKey) {
if (!predicate.apply(this.owner.allocatedDefaultKeyValue)) {
return predicate;
}
}
final KType[] keys = ((KType[])(this.owner.keys));
final short[] values = ((this.owner.values));
for (int slot = 0; slot < keys.length; slot++) {
if ((!(((keys)[(slot)]) == null))) {
if (!predicate.apply(values[slot])) {
break;
}
}
}
return predicate;
}
@Override
public ValuesIterator iterator() {
// return new ValuesIterator();
return this.valuesIteratorPool.borrow();
}
/**
* {@inheritDoc}
* Indeed removes all the (key,value) pairs matching
* (key ? , e) with the same e, from the map.
*/
@Override
public int removeAll(final short e) {
final int before = this.owner.size();
if (this.owner.allocatedDefaultKey) {
if (((e) == (this.owner.allocatedDefaultKeyValue))) {
this.owner.allocatedDefaultKey = false;
}
}
final KType[] keys = ((KType[])(this.owner.keys));
final short[] values = ((this.owner.values));
for (int slot = 0; slot < keys.length;) {
if ((!(((keys)[(slot)]) == null)) && ((e) == (values[slot]))) {
shiftConflictingKeys(slot);
// Shift, do not increment slot.
} else {
slot++;
}
}
return before - this.owner.size();
}
/**
* {@inheritDoc}
* Indeed removes all the (key,value) pairs matching
* the predicate for the values, from the map.
*/
@Override
public int removeAll(final ShortPredicate predicate) {
final int before = this.owner.size();
if (this.owner.allocatedDefaultKey) {
if (predicate.apply(this.owner.allocatedDefaultKeyValue)) {
this.owner.allocatedDefaultKey = false;
}
}
final KType[] keys = ((KType[])(this.owner.keys));
final short[] values = ((this.owner.values));
for (int slot = 0; slot < keys.length;) {
if ((!(((keys)[(slot)]) == null)) && predicate.apply(values[slot])) {
shiftConflictingKeys(slot);
// Shift, do not increment slot.
} else {
slot++;
}
}
return before - this.owner.size();
}
/**
* {@inheritDoc}
* Alias for clear() the whole map.
*/
@Override
public void clear() {
this.owner.clear();
}
/**
* internal pool of ValuesIterator
*/
protected final IteratorPool valuesIteratorPool = new IteratorPool(
new ObjectFactory() {
@Override
public ValuesIterator create() {
return new ValuesIterator();
}
@Override
public void initialize(final ValuesIterator obj) {
obj.cursor.index = ObjectShortHashMap.this.keys.length + 1;
}
@Override
public void reset(final ValuesIterator obj) {
}
});
@Override
public short[] toArray(final short[] target) {
int count = 0;
if (this.owner.allocatedDefaultKey) {
target[count++] = this.owner.allocatedDefaultKeyValue;
}
final KType[] keys = ((KType[])(this.owner.keys));
final short[] values = ((this.owner.values));
for (int i = 0; i < values.length; i++) {
if ((!(((keys)[(i)]) == null))) {
target[count++] = values[i];
}
}
assert count == this.owner.size();
return target;
}
}
/**
* An iterator over the set of values.
* Holds a ObjectCursor returning (value, index) = (short value, index the position in buffer {@link ObjectShortHashMap#values},
* or values.length for value = {@link ObjectShortHashMap#allocatedDefaultKeyValue}).
*/
public final class ValuesIterator extends AbstractIterator
{
public final ShortCursor cursor;
public ValuesIterator() {
this.cursor = new ShortCursor();
this.cursor.index = -2;
}
/**
* Iterate backwards w.r.t the buffer, to
* minimize collision chains when filling another hash container (ex. with putAll())
*/
@Override
protected ShortCursor fetch() {
if (this.cursor.index == ObjectShortHashMap.this.values.length + 1) {
if (ObjectShortHashMap.this.allocatedDefaultKey) {
this.cursor.index = ObjectShortHashMap.this.values.length;
this.cursor.value = ObjectShortHashMap.this.allocatedDefaultKeyValue;
return this.cursor;
}
//no value associated with the default key, continue iteration...
this.cursor.index = ObjectShortHashMap.this.keys.length;
}
int i = this.cursor.index - 1;
while (i >= 0 && !(!(((((KType[])(ObjectShortHashMap.this.keys)))[(i)]) == null))) {
i--;
}
if (i == -1) {
return done();
}
this.cursor.index = i;
this.cursor.value = ((ObjectShortHashMap.this.values[i]));
return this.cursor;
}
}
/**
* {@inheritDoc}
*/
@Override
public ObjectShortHashMap clone() {
//clone to size() to prevent some cases of exponential sizes,
final ObjectShortHashMap cloned = new ObjectShortHashMap(this.size(), this.loadFactor);
//We must NOT clone because of independent perturbations seeds
cloned.putAll(this);
return cloned;
}
/**
* 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 (final ObjectShortCursor cursor : this) {
if (!first) {
buffer.append(", ");
}
buffer.append(cursor.key);
buffer.append("=>");
buffer.append(cursor.value);
first = false;
}
buffer.append("]");
return buffer.toString();
}
/**
* Creates a hash map from two index-aligned arrays of key-value pairs. Default load factor is used.
*/
public static ObjectShortHashMap from(final KType[] keys, final short[] values) {
if (keys.length != values.length) {
throw new IllegalArgumentException("Arrays of keys and values must have an identical length.");
}
final ObjectShortHashMap map = new ObjectShortHashMap(keys.length);
for (int i = 0; i < keys.length; i++) {
map.put(keys[i], values[i]);
}
return map;
}
/**
* Create a hash map from another associative container. (constructor shortcut) Default load factor is used.
*/
public static ObjectShortHashMap from(
final ObjectShortAssociativeContainer container) {
return new ObjectShortHashMap(container);
}
/**
* Create a new hash map without providing the full generic signature
* (constructor shortcut).
*/
public static ObjectShortHashMap newInstance() {
return new ObjectShortHashMap();
}
/**
* Create a new hash map with initial capacity and load factor control.
* (constructor shortcut).
*/
public static ObjectShortHashMap newInstance(final int initialCapacity,
final double loadFactor) {
return new ObjectShortHashMap(initialCapacity, loadFactor);
}
/**
* Returns the "default value" value used in containers methods returning
* "default value"
*/
@Override
public short getDefaultValue() {
return this.defaultValue;
}
/**
* Set the "default value" value to be used in containers methods returning
* "default value"
*/
@Override
public void setDefaultValue(final short defaultValue) {
this.defaultValue = defaultValue;
}
//Test for existence in template
private int probe_distance(final int slot, final int[] cache) {
final int rh = cache[slot];
if (slot < rh) {
//wrap around
return slot - rh + cache.length;
}
return slot - rh;
}
}