Package com.carrotsearch.hppc

Class ObjectObjectHashMap<KType,​VType>

    • Field Detail

      • keys

        public Object[] 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(KType), "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

      • ObjectObjectHashMap

        public ObjectObjectHashMap()
        New instance with sane defaults.

      • ObjectObjectHashMap

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

      • ObjectObjectHashMap

        public ObjectObjectHashMap​(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).

      • ObjectObjectHashMap

        public ObjectObjectHashMap​(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.

    • Method Detail

      • put

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

      • putAll

        public int putAll​(ObjectObjectAssociativeContainer<? extends KType,​? 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 ObjectObjectMap<KType,​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 ObjectObjectCursor<? extends KType,​? extends VType>> iterable)
        Puts all key/value pairs from a given iterable into this map.
        Specified by:
        putAll in interface ObjectObjectMap<KType,​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​(KType 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​(KType 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 ObjectObjectMap<KType,​VType>

      • removeAll

        public int removeAll​(ObjectContainer<? super KType> 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 ObjectObjectAssociativeContainer<KType,​VType>
        Returns:
        Returns the number of elements actually removed as a result of this call.

      • get

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

      • 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 ObjectObjectMap<KType,​VType>
        Parameters:
        index - The index of an existing key.
        Returns:
        Returns the previous value associated with the key.
        See Also:
        ObjectObjectMap.indexOf(KType)

      • hashCode

        public int hashCode()
        Specified by:
        hashCode in interface ObjectObjectMap<KType,​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 ObjectObjectMap and both objects contains exactly the same key-value pairs.
        Specified by:
        equals in interface ObjectObjectMap<KType,​VType>
        Overrides:
        equals in class Object

      • 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<ObjectObjectCursor<KType,​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 Iterable<KType>
        Specified by:
        iterator in interface ObjectObjectAssociativeContainer<KType,​VType>

      • forEach

        public <T extends ObjectObjectPredicate<? super KType,​? super VType>> T forEach​(T predicate)
        Applies a given predicate to all keys-value pairs in this container. Returns the argument (any subclass of ObjectObjectPredicate. 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 ObjectObjectAssociativeContainer<KType,​VType>

      • values

        public ObjectCollection<VType> values()
        Description copied from interface: ObjectObjectAssociativeContainer
        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 ObjectObjectAssociativeContainer<KType,​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: ObjectObjectMap
        Visually depict the distribution of keys.
        Specified by:
        visualizeKeyDistribution in interface ObjectObjectMap<KType,​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 <KType,​VType> ObjectObjectHashMap<KType,​VType> from​(KType[] keys,
                                                                              VType[] values)
        Creates a hash map from two index-aligned arrays of key-value pairs.

      • hashKey

        protected int hashKey​(KType 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​(KType[] 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,
                                            KType 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.

      • equals

        protected boolean equals​(Object v1,
                         Object v2)