Package com.carrotsearch.hppc

Class IntObjectHashMap<VType>

    • Field Detail

      • keys

        public int[] keys
        The array holding keys.

      • values

        public Object[] values
        The array holding values.

      • keyMixer

        protected int keyMixer
        We perturb hash values with a container-unique seed to avoid problems with nearly-sorted-by-hash values on iterations.
        See Also:
        hashKey(int), "http://issues.carrot2.org/browse/HPPC-80", "http://issues.carrot2.org/browse/HPPC-103"

      • assigned

        protected int assigned
        The number of stored keys (assigned key slots), excluding the special "empty" key, if any (use size() instead).
        See Also:
        size()

      • mask

        protected int mask
        Mask for slot scans in keys.

      • resizeAt

        protected int resizeAt
        Expand (rehash) keys when assigned hits this value.

      • hasEmptyKey

        protected boolean hasEmptyKey
        Special treatment for the "empty slot" key marker.

      • loadFactor

        protected double loadFactor
        The load factor for keys.

    • Constructor Detail

      • IntObjectHashMap

        public IntObjectHashMap()
        New instance with sane defaults.

      • IntObjectHashMap

        public IntObjectHashMap​(int expectedElements)
        New instance with sane defaults.
        Parameters:
        expectedElements - The expected number of elements guaranteed not to cause buffer expansion (inclusive).

      • IntObjectHashMap

        public IntObjectHashMap​(int expectedElements,
                        double loadFactor)
        New instance with sane defaults.
        Parameters:
        expectedElements - The expected number of elements guaranteed not to cause buffer expansion (inclusive).
        loadFactor - The load factor for internal buffers. Insane load factors (zero, full capacity) are rejected by verifyLoadFactor(double).

      • IntObjectHashMap

        public IntObjectHashMap​(int expectedElements,
                        double loadFactor,
                        HashOrderMixingStrategy orderMixer)
        New instance with the provided defaults.
        Parameters:
        expectedElements - The expected number of elements guaranteed not to cause a rehash (inclusive).
        loadFactor - The load factor for internal buffers. Insane load factors (zero, full capacity) are rejected by verifyLoadFactor(double).
        orderMixer - Hash key order mixing strategy. See HashOrderMixing for predefined implementations. Use constant mixers only if you understand the potential consequences.

      • IntObjectHashMap

        public IntObjectHashMap​(IntObjectAssociativeContainer<? extends VType> container)
        Create a hash map from all key-value pairs of another container.

    • Method Detail

      • put

        public VType put​(int key,
                 VType value)
        Place a given key and value in the container.
        Specified by:
        put in interface IntObjectMap<VType>
        Returns:
        The value previously stored under the given key in the map is returned.

      • putAll

        public int putAll​(IntObjectAssociativeContainer<? extends VType> container)
        Puts all keys from another container to this map, replacing the values of existing keys, if such keys are present.
        Specified by:
        putAll in interface IntObjectMap<VType>
        Returns:
        Returns the number of keys added to the map as a result of this call (not previously present in the map). Values of existing keys are overwritten.

      • putAll

        public int putAll​(Iterable<? extends IntObjectCursor<? extends VType>> iterable)
        Puts all key/value pairs from a given iterable into this map.
        Specified by:
        putAll in interface IntObjectMap<VType>
        Returns:
        Returns the number of keys added to the map as a result of this call (not previously present in the map). Values of existing keys are overwritten.

      • putIfAbsent

        public boolean putIfAbsent​(int key,
                           VType value)
        Trove-inspired API method. An equivalent of the following code: 
         if (!map.containsKey(key)) map.put(value);
        Parameters:
        key - The key of the value to check.
        value - The value to put if key does not exist.
        Returns:
        true if key did not exist and value was placed in the map.

      • remove

        public VType remove​(int key)
        Remove all values at the given key. The default value for the key type is returned if the value does not exist in the map.
        Specified by:
        remove in interface IntObjectMap<VType>

      • removeAll

        public int removeAll​(IntContainer other)
        Removes all keys (and associated values) present in a given container. An alias to: 
         keys().removeAll(container)
        but with no additional overhead.
        Specified by:
        removeAll in interface IntObjectAssociativeContainer<VType>
        Returns:
        Returns the number of elements actually removed as a result of this call.

      • removeAll

        public int removeAll​(IntPredicate predicate)
        Removes all keys (and associated values) for which the predicate returns true.
        Specified by:
        removeAll in interface IntObjectAssociativeContainer<VType>
        Returns:
        Returns the number of elements actually removed as a result of this call.

      • get

        public VType get​(int key)
        Specified by:
        get in interface IntObjectMap<VType>
        Returns:
        Returns the value associated with the given key or the default value for the value type, if the key is not associated with any value. For numeric value types, this default value is 0, for object types it is null.

      • getOrDefault

        public VType getOrDefault​(int key,
                          VType defaultValue)
        Specified by:
        getOrDefault in interface IntObjectMap<VType>
        Returns:
        Returns the value associated with the given key or the provided default value if the key is not associated with any value.

      • indexOf

        public int indexOf​(int key)
        Returns a logical "index" of a given key that can be used to speed up follow-up value setters or getters in certain scenarios (conditional logic). The semantics of "indexes" are not strictly defined. Indexes may (and typically won't be) contiguous. The index is valid only between map modifications (it will not be affected by read-only operations like iteration or value retrievals).
        Specified by:
        indexOf in interface IntObjectMap<VType>
        Parameters:
        key - The key to locate in the map.
        Returns:
        A non-negative value of the logical "index" of the key in the map or a negative value if the key did not exist.
        See Also:
        IntObjectMap.indexExists(int), IntObjectMap.indexGet(int), IntObjectMap.indexInsert(int, int, VType), IntObjectMap.indexReplace(int, VType)

      • indexExists

        public boolean indexExists​(int index)
        Specified by:
        indexExists in interface IntObjectMap<VType>
        Parameters:
        index - The index of a given key, as returned from IntObjectMap.indexOf(int).
        Returns:
        Returns true if the index corresponds to an existing key or false otherwise. This is equivalent to checking whether the index is a positive value (existing keys) or a negative value (non-existing keys).
        See Also:
        IntObjectMap.indexOf(int)

      • indexGet

        public VType indexGet​(int index)
        Returns the value associated with an existing key.
        Specified by:
        indexGet in interface IntObjectMap<VType>
        Parameters:
        index - The index of an existing key.
        Returns:
        Returns the value currently associated with the key.
        See Also:
        IntObjectMap.indexOf(int)

      • indexReplace

        public VType indexReplace​(int index,
                          VType newValue)
        Replaces the value associated with an existing key and returns any previous value stored for that key.
        Specified by:
        indexReplace in interface IntObjectMap<VType>
        Parameters:
        index - The index of an existing key.
        Returns:
        Returns the previous value associated with the key.
        See Also:
        IntObjectMap.indexOf(int)

      • indexInsert

        public void indexInsert​(int index,
                        int key,
                        VType value)
        Inserts a key-value pair for a key that is not present in the map. This method may help in avoiding double recalculation of the key's hash.
        Specified by:
        indexInsert in interface IntObjectMap<VType>
        Parameters:
        index - The index of a previously non-existing key, as returned from IntObjectMap.indexOf(int).
        See Also:
        IntObjectMap.indexOf(int)

      • release

        public void release()
        Removes all elements from the collection and additionally releases any internal buffers. Typically, if the object is to be reused, a simple IntObjectMap.clear() should be a better alternative since it'll avoid reallocation.
        Specified by:
        release in interface IntObjectMap<VType>
        See Also:
        IntObjectMap.clear()

      • hashCode

        public int hashCode()
        Specified by:
        hashCode in interface IntObjectMap<VType>
        Overrides:
        hashCode in class Object
        Returns:
        A hash code of elements stored in the map. The hash code is defined as a sum of hash codes of keys and values stored within the set). Because sum is commutative, this ensures that different order of elements in a set does not affect the hash code.

      • equals

        public boolean equals​(Object obj)
        Compares the specified object with this set for equality. Returns true if and only if the specified object is also a IntObjectMap and both objects contains exactly the same key-value pairs.
        Specified by:
        equals in interface IntObjectMap<VType>
        Overrides:
        equals in class Object

      • equalElements

        protected boolean equalElements​(IntObjectHashMap<?> other)
        Return true if all keys of some other container exist in this container. Values are compared using Object.equals(Object) method.

      • ensureCapacity

        public void ensureCapacity​(int expectedElements)
        Ensure this container can hold at least the given number of keys (entries) without resizing its buffers.
        Specified by:
        ensureCapacity in interface Preallocable
        Parameters:
        expectedElements - The total number of keys, inclusive.

      • iterator

        public Iterator<IntObjectCursor<VType>> iterator()
        Returns a cursor over the entries (key-value pairs) in this map. The iterator is implemented as a cursor and it returns the same cursor instance on every call to Iterator.next(). To read the current key and value use the cursor's public fields. An example is shown below. 
         for (IntShortCursor c : intShortMap) {
   System.out.println("index=" + c.index + " key=" + c.key + " value=" + c.value);
 }

        The index field inside the cursor gives the internal index inside the container's implementation. The interpretation of this index depends on to the container.

        Specified by:
        iterator in interface IntObjectAssociativeContainer<VType>
        Specified by:
        iterator in interface Iterable<VType>

      • forEach

        public <T extends IntObjectProcedure<? super VType>> T forEach​(T procedure)
        Applies a given procedure to all keys-value pairs in this container. Returns the argument (any subclass of IntObjectProcedure. This lets the caller to call methods of the argument by chaining the call (even if the argument is an anonymous type) to retrieve computed values, for example.
        Specified by:
        forEach in interface IntObjectAssociativeContainer<VType>

      • forEach

        public <T extends IntObjectPredicate<? super VType>> T forEach​(T predicate)
        Applies a given predicate to all keys-value pairs in this container. Returns the argument (any subclass of IntObjectPredicate. This lets the caller to call methods of the argument by chaining the call (even if the argument is an anonymous type) to retrieve computed values, for example. The iteration is continued as long as the predicate returns true.
        Specified by:
        forEach in interface IntObjectAssociativeContainer<VType>

      • values

        public ObjectCollection<VType> values()
        Description copied from interface: IntObjectAssociativeContainer
        Returns a container view of all values present in this container. The returned collection is a view over the key set and any modifications (if allowed) introduced to the collection will propagate to the associative container immediately.
        Specified by:
        values in interface IntObjectAssociativeContainer<VType>
        Returns:
        Returns a container with all values stored in this map.

      • toString

        public String toString()
        Convert the contents of this map to a human-friendly string.
        Overrides:
        toString in class Object

      • visualizeKeyDistribution

        public String visualizeKeyDistribution​(int characters)
        Description copied from interface: IntObjectMap
        Visually depict the distribution of keys.
        Specified by:
        visualizeKeyDistribution in interface IntObjectMap<VType>
        Parameters:
        characters - The number of characters to "squeeze" the entire buffer into.
        Returns:
        Returns a sequence of characters where '.' depicts an empty fragment of the internal buffer and 'X' depicts full or nearly full capacity within the buffer's range and anything between 1 and 9 is between.

      • from

        public static <VType> IntObjectHashMap<VType> from​(int[] keys,
                                                   VType[] values)
        Creates a hash map from two index-aligned arrays of key-value pairs.

      • hashKey

        protected int hashKey​(int key)
        Returns a hash code for the given key.

        The default implementation mixes the hash of the key with 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.

      • verifyLoadFactor

        protected double verifyLoadFactor​(double loadFactor)
        Validate load factor range and return it. Override and suppress if you need insane load factors.

      • rehash

        protected void rehash​(int[] fromKeys,
                      VType[] fromValues)
        Rehash from old buffers to new buffers.

      • allocateBuffers

        protected void allocateBuffers​(int arraySize)
        Allocate new internal buffers. This method attempts to allocate and assign internal buffers atomically (either allocations succeed or not).

      • allocateThenInsertThenRehash

        protected void allocateThenInsertThenRehash​(int slot,
                                            int pendingKey,
                                            VType pendingValue)
        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.

      • shiftConflictingKeys

        protected void shiftConflictingKeys​(int gapSlot)
        Shift all the slot-conflicting keys and values allocated to (and including) slot.