Package com.carrotsearch.hppc

Class IntIntHashMap

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      class  IntIntHashMap.KeysContainer
      A view of the keys inside this hash map.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      protected int assigned
      The number of stored keys (assigned key slots), excluding the special "empty" key, if any (use size() instead).
      protected boolean hasEmptyKey
      Special treatment for the "empty slot" key marker.
      protected int iterationSeed
      Seed used to ensure the hash iteration order is different from an iteration to another.
      int[] keys
      The array holding keys.
      protected double loadFactor
      The load factor for keys.
      protected int mask
      Mask for slot scans in keys.
      protected int resizeAt
      Expand (rehash) keys when assigned hits this value.
      int[] values
      The array holding values.

    • Constructor Summary

      Constructors 
      Constructor Description
      IntIntHashMap()
      New instance with sane defaults.
      IntIntHashMap​(int expectedElements)
      New instance with sane defaults.
      IntIntHashMap​(int expectedElements, double loadFactor)
      New instance with the provided defaults.
      IntIntHashMap​(IntIntAssociativeContainer container)
      Create a hash map from all key-value pairs of another container.

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      int addTo​(int key, int incrementValue)
      Adds incrementValue to any existing value for the given key or inserts incrementValue if key did not previously exist.
      protected void allocateBuffers​(int arraySize)
      Allocate new internal buffers.
      protected void allocateThenInsertThenRehash​(int slot, int pendingKey, int 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.
      void clear()
      Clear all keys and values in the container.
      IntIntHashMap clone()
      boolean containsKey​(int key)
      Returns true if this container has an association to a value for the given key.
      void ensureCapacity​(int expectedElements)
      Ensure this container can hold at least the given number of keys (entries) without resizing its buffers.
      protected boolean equalElements​(IntIntHashMap other)
      Return true if all keys of some other container exist in this container.
      boolean equals​(java.lang.Object obj)
      Compares the specified object with this set for equality.
      <T extends IntIntProcedure>
      T      		 forEach​(T procedure)
      Applies a given procedure to all keys-value pairs in this container.
      static IntIntHashMap from​(int[] keys, int[] values)
      Creates a hash map from two index-aligned arrays of key-value pairs.
      int get​(int key)
      int getOrDefault​(int key, int defaultValue)
      int hashCode()
      protected int hashKey​(int key)
      Returns a hash code for the given key.
      boolean indexExists​(int index)
      int indexGet​(int index)
      Returns the value associated with an existing key.
      void indexInsert​(int index, int key, int value)
      Inserts a key-value pair for a key that is not present in the map.
      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).
      int indexRemove​(int index)
      Removes a key-value pair at an index previously acquired from IntIntMap.indexOf(int).
      int indexReplace​(int index, int newValue)
      Replaces the value associated with an existing key and returns any previous value stored for that key.
      boolean isEmpty()
      java.util.Iterator<IntIntCursor> iterator()
      Returns a cursor over the entries (key-value pairs) in this map.
      IntIntHashMap.KeysContainer keys()
      Returns a specialized view of the keys of this associated container.
      protected int nextIterationSeed()
      Provides the next iteration seed used to build the iteration starting slot and offset increment.
      int put​(int key, int value)
      Place a given key and value in the container.
      int putAll​(IntIntAssociativeContainer container)
      Puts all keys from another container to this map, replacing the values of existing keys, if such keys are present.
      int putAll​(java.lang.Iterable<? extends IntIntCursor> iterable)
      Puts all key/value pairs from a given iterable into this map.
      boolean putIfAbsent​(int key, int value)
      Trove-inspired API method.
      int putOrAdd​(int key, int putValue, int incrementValue)
      If key exists, putValue is inserted into the map, otherwise any existing value is incremented by additionValue.
      long ramBytesAllocated()
      Allocated memory estimation
      long ramBytesUsed()
      Bytes that is actually been used
      protected void rehash​(int[] fromKeys, int[] fromValues)
      Rehash from old buffers to new buffers.
      void release()
      Removes all elements from the collection and additionally releases any internal buffers.
      int remove​(int key)
      Remove all values at the given key.
      int removeAll​(IntContainer other)
      Removes all keys (and associated values) present in a given container.
      int removeAll​(IntIntPredicate predicate)
      Removes all keys (and associated values) for which the predicate returns true.
      int removeAll​(IntPredicate predicate)
      Removes all keys (and associated values) for which the predicate returns true.
      protected void shiftConflictingKeys​(int gapSlot)
      Shift all the slot-conflicting keys and values allocated to (and including) slot.
      int size()
      java.lang.String toString()
      Convert the contents of this map to a human-friendly string.
      IntCollection values()
      Returns a container view of all values present in this container.
      protected double verifyLoadFactor​(double loadFactor)
      Validate load factor range and return it.
      java.lang.String visualizeKeyDistribution​(int characters)
      Visually depict the distribution of keys.

      • Methods inherited from class java.lang.Object

        finalize, getClass, notify, notifyAll, wait, wait, wait

      • Methods inherited from interface java.lang.Iterable

        forEach, spliterator

    • Field Detail

      • keys

        public int[] keys
        The array holding keys.

      • values

        public int[] values
        The array holding values.

      • 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.

      • iterationSeed

        protected int iterationSeed
        Seed used to ensure the hash iteration order is different from an iteration to another.

    • Constructor Detail

      • IntIntHashMap

        public IntIntHashMap()
        New instance with sane defaults.

      • IntIntHashMap

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

      • IntIntHashMap

        public IntIntHashMap​(int expectedElements,
                     double loadFactor)
        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).

      • IntIntHashMap

        public IntIntHashMap​(IntIntAssociativeContainer container)
        Create a hash map from all key-value pairs of another container.

    • Method Detail

      • put

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

      • putAll

        public int putAll​(IntIntAssociativeContainer 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 IntIntMap
        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​(java.lang.Iterable<? extends IntIntCursor> iterable)
        Puts all key/value pairs from a given iterable into this map.
        Specified by:
        putAll in interface IntIntMap
        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,
                           int 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.

      • putOrAdd

        public int putOrAdd​(int key,
                    int putValue,
                    int incrementValue)
        If key exists, putValue is inserted into the map, otherwise any existing value is incremented by additionValue.
        Specified by:
        putOrAdd in interface IntIntMap
        Parameters:
        key - The key of the value to adjust.
        putValue - The value to put if key does not exist.
        incrementValue - The value to add to the existing value if key exists.
        Returns:
        Returns the current value associated with key (after changes).

      • addTo

        public int addTo​(int key,
                 int incrementValue)
        Adds incrementValue to any existing value for the given key or inserts incrementValue if key did not previously exist.
        Specified by:
        addTo in interface IntIntMap
        Parameters:
        key - The key of the value to adjust.
        incrementValue - The value to put or add to the existing value if key exists.
        Returns:
        Returns the current value associated with key (after changes).

      • remove

        public int 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 IntIntMap

      • 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 IntIntAssociativeContainer
        Returns:
        Returns the number of elements actually removed as a result of this call.

      • removeAll

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

      • get

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

      • containsKey

        public boolean containsKey​(int key)
        Returns true if this container has an association to a value for the given key.
        Specified by:
        containsKey in interface IntIntAssociativeContainer

      • 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 IntIntMap
        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:
        IntIntMap.indexExists(int), IntIntMap.indexGet(int), IntIntMap.indexInsert(int, int, int), IntIntMap.indexReplace(int, int)

      • indexExists

        public boolean indexExists​(int index)
        Specified by:
        indexExists in interface IntIntMap
        Parameters:
        index - The index of a given key, as returned from IntIntMap.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:
        IntIntMap.indexOf(int)

      • indexGet

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

      • indexReplace

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

      • indexInsert

        public void indexInsert​(int index,
                        int key,
                        int 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 IntIntMap
        Parameters:
        index - The index of a previously non-existing key, as returned from IntIntMap.indexOf(int).
        See Also:
        IntIntMap.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 IntIntMap.clear() should be a better alternative since it'll avoid reallocation.
        Specified by:
        release in interface IntIntMap
        See Also:
        IntIntMap.clear()

      • size

        public int size()
        Specified by:
        size in interface IntIntAssociativeContainer
        Returns:
        Returns the current size (number of assigned keys) in the container.

      • isEmpty

        public boolean isEmpty()
        Specified by:
        isEmpty in interface IntIntAssociativeContainer
        Returns:
        Return true if this hash map contains no assigned keys.

      • hashCode

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

      • equalElements

        protected boolean equalElements​(IntIntHashMap other)
        Return true if all keys of some other container exist in this container.

      • 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.

      • ramBytesAllocated

        public long ramBytesAllocated()
        Description copied from interface: Accountable
        Allocated memory estimation
        Specified by:
        ramBytesAllocated in interface Accountable
        Returns:
        Ram allocated in bytes

      • ramBytesUsed

        public long ramBytesUsed()
        Description copied from interface: Accountable
        Bytes that is actually been used
        Specified by:
        ramBytesUsed in interface Accountable
        Returns:
        Ram used in bytes

      • nextIterationSeed

        protected int nextIterationSeed()
        Provides the next iteration seed used to build the iteration starting slot and offset increment. This method does not need to be synchronized, what matters is that each thread gets a sequence of varying seeds.

      • iterator

        public java.util.Iterator<IntIntCursor> 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 IntIntAssociativeContainer
        Specified by:
        iterator in interface java.lang.Iterable<IntIntCursor>

      • forEach

        public <T extends IntIntProcedure> T forEach​(T procedure)
        Applies a given procedure to all keys-value pairs in this container. Returns the argument (any subclass of IntIntProcedure. 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 IntIntAssociativeContainer

      • forEach

        public <T extends IntIntPredicate> T forEach​(T predicate)
        Applies a given predicate to all keys-value pairs in this container. Returns the argument (any subclass of IntIntPredicate. 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 IntIntAssociativeContainer

      • values

        public IntCollection values()
        Description copied from interface: IntIntAssociativeContainer
        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 IntIntAssociativeContainer
        Returns:
        Returns a container with all values stored in this map.

      • clone

        public IntIntHashMap clone()
        Overrides:
        clone in class java.lang.Object

      • toString

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

      • visualizeKeyDistribution

        public java.lang.String visualizeKeyDistribution​(int characters)
        Description copied from interface: IntIntMap
        Visually depict the distribution of keys.
        Specified by:
        visualizeKeyDistribution in interface IntIntMap
        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 IntIntHashMap from​(int[] keys,
                                 int[] 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 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,
                      int[] 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,
                                            int 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.