Class KeyComparatorHashMap<K,V>

java.lang.Object
java.util.AbstractMap<K,V>
org.glassfish.jersey.internal.util.collection.KeyComparatorHashMap<K,V>
Type Parameters:
K - Type of keys
V - Type of values
All Implemented Interfaces:
Serializable, Cloneable, Map<K,V>
Direct Known Subclasses:
KeyComparatorLinkedHashMap

public class KeyComparatorHashMap<K,V> extends AbstractMap<K,V> implements Map<K,V>, Cloneable, Serializable
A implementation similar to HashMap but supports the comparison of keys using a KeyComparator.
See Also:
  • Field Details

    • serialVersionUID

      private static final long serialVersionUID
      See Also:
    • DEFAULT_INITIAL_CAPACITY

      static final int DEFAULT_INITIAL_CAPACITY
      The default initial capacity - MUST be a power of two.
      See Also:
    • MAXIMUM_CAPACITY

      static final int MAXIMUM_CAPACITY
      The maximum capacity, used if a higher value is implicitly specified by either of the constructors with arguments. MUST be a power of two <= 1<<30.
      See Also:
    • DEFAULT_LOAD_FACTOR

      static final float DEFAULT_LOAD_FACTOR
      The load factor used when none specified in constructor.
      See Also:
    • table

      transient KeyComparatorHashMap.Entry<K,V>[] table
      The table, resized as necessary. Length MUST Always be a power of two.
    • size

      transient int size
      The number of key-value mappings contained in this identity hash map.
    • threshold

      int threshold
      The next ss value at which to resize (capacity * load factor).
    • loadFactor

      final float loadFactor
      The load factor for the hash table.
    • modCount

      transient volatile int modCount
      The number of times this HashMap has been structurally modified Structural modifications are those that change the number of mappings in the HashMap or otherwise modify its internal structure (e.g., rehash). This field is used to make iterators on Collection-views of the HashMap fail-fast. (See ConcurrentModificationException).
    • keyComparator

      final KeyComparator<K> keyComparator
    • NULL_KEY

      static final Object NULL_KEY
      Value representing null keys inside tables.
    • entrySet

      private transient Set<Map.Entry<K,V>> entrySet
  • Constructor Details

    • KeyComparatorHashMap

      public KeyComparatorHashMap(int initialCapacity, float loadFactor, KeyComparator<K> keyComparator)
      Constructs an empty HashMap with the specified initial capacity and load factor.
      Parameters:
      initialCapacity - The initial capacity.
      loadFactor - The load factor.
      keyComparator - the map key comparator.
      Throws:
      IllegalArgumentException - if the initial capacity is negative or the load factor is nonpositive.
    • KeyComparatorHashMap

      public KeyComparatorHashMap(int initialCapacity, KeyComparator<K> keyComparator)
      Constructs an empty HashMap with the specified initial capacity and the default load factor (0.75).
      Parameters:
      initialCapacity - the initial capacity.
      keyComparator - the map key comparator.
      Throws:
      IllegalArgumentException - if the initial capacity is negative.
    • KeyComparatorHashMap

      public KeyComparatorHashMap(KeyComparator<K> keyComparator)
      Constructs an empty HashMap with the default initial capacity (16) and the default load factor (0.75).
      Parameters:
      keyComparator - the map key comparator.
    • KeyComparatorHashMap

      public KeyComparatorHashMap(Map<? extends K,? extends V> m, KeyComparator<K> keyComparator)
      Constructs a new HashMap with the same mappings as the specified Map. The HashMap is created with default load factor (0.75) and an initial capacity sufficient to hold the mappings in the specified Map.
      Parameters:
      m - the map whose mappings are to be placed in this map.
      keyComparator - the comparator
      Throws:
      NullPointerException - if the specified map is null.
  • Method Details

    • getModCount

      public int getModCount()
      Get the number of times this HashMap has been structurally modified Structural modifications are those that change the number of mappings in the HashMap or otherwise modify its internal structure (e.g., rehash).
      Returns:
      return the modification count.
    • init

      void init()
      Initialization hook for subclasses.

      This method is called in all pseudo-constructors (clone, readObject) after HashMap has been initialized but before any entries have been inserted. (In the absence of this method, readObject would require explicit knowledge of subclasses.)

    • maskNull

      static <T> T maskNull(T key)
      Returns internal representation for key. Use NULL_KEY if key is null.
    • isNull

      static <T> boolean isNull(T key)
    • unmaskNull

      static <T> T unmaskNull(T key)
      Returns key represented by specified internal representation.
    • hash

      static int hash(Object x)
      Returns a hash value for the specified object. In addition to the object's own hashCode, this method applies a "supplemental hash function," which defends against poor quality hash functions. This is critical because HashMap uses power-of two length hash tables.

      The shift distances in this function were chosen as the result of an automated search over the entire four-dimensional search space.

    • eq

      static boolean eq(Object x, Object y)
      Check for equality of non-null reference x and possibly-null y.
    • indexFor

      static int indexFor(int h, int length)
      Returns index for hash code h.
    • size

      public int size()
      Returns the number of key-value mappings in this map.
      Specified by:
      size in interface Map<K,V>
      Overrides:
      size in class AbstractMap<K,V>
      Returns:
      the number of key-value mappings in this map.
    • isEmpty

      public boolean isEmpty()
      Returns true if this map contains no key-value mappings.
      Specified by:
      isEmpty in interface Map<K,V>
      Overrides:
      isEmpty in class AbstractMap<K,V>
      Returns:
      true if this map contains no key-value mappings.
    • keyComparatorHash

      int keyComparatorHash(K k)
    • hash

      int hash(int h)
    • keyComparatorEq

      boolean keyComparatorEq(K x, K y)
      Check for equality of non-null reference x and possibly-null y.
    • get

      public V get(Object key)
      Returns the value to which the specified key is mapped in this identity hash map, or null if the map contains no mapping for this key. A return value of null does not necessarily indicate that the map contains no mapping for the key; it is also possible that the map explicitly maps the key to null. The containsKey method may be used to distinguish these two cases.
      Specified by:
      get in interface Map<K,V>
      Overrides:
      get in class AbstractMap<K,V>
      Parameters:
      key - the key whose associated value is to be returned.
      Returns:
      the value to which this map maps the specified key, or null if the map contains no mapping for this key.
      See Also:
    • containsKey

      public boolean containsKey(Object key)
      Returns true if this map contains a mapping for the specified key.
      Specified by:
      containsKey in interface Map<K,V>
      Overrides:
      containsKey in class AbstractMap<K,V>
      Parameters:
      key - The key whose presence in this map is to be tested
      Returns:
      true if this map contains a mapping for the specified key.
    • getEntry

      KeyComparatorHashMap.Entry<K,V> getEntry(K key)
      Returns the entry associated with the specified key in the HashMap. Returns null if the HashMap contains no mapping for this key.
    • put

      public V put(K key, V value)
      Associates the specified value with the specified key in this map. If the map previously contained a mapping for this key, the old value is replaced.
      Specified by:
      put in interface Map<K,V>
      Overrides:
      put in class AbstractMap<K,V>
      Parameters:
      key - key with which the specified value is to be associated.
      value - value to be associated with the specified key.
      Returns:
      previous value associated with specified key, or null if there was no mapping for key. A null return can also indicate that the HashMap previously associated null with the specified key.
    • putForCreate

      private void putForCreate(K key, V value)
      This method is used instead of put by constructors and pseudoconstructors (clone, readObject). It does not resize the table, check for comodification, etc. It calls createEntry rather than addEntry.
    • putAllForCreate

      private void putAllForCreate(Map<? extends K,? extends V> m)
    • resize

      void resize(int newCapacity)
      Rehashes the contents of this map into a new array with a larger capacity. This method is called automatically when the number of keys in this map reaches its threshold.

      If current capacity is MAXIMUM_CAPACITY, this method does not resize the map, but sets threshold to Integer.MAX_VALUE. This has the effect of preventing future calls.

      Parameters:
      newCapacity - the new capacity, MUST be a power of two; must be greater than current capacity unless current capacity is MAXIMUM_CAPACITY (in which case value is irrelevant).
    • transfer

      void transfer(KeyComparatorHashMap.Entry<K,V>[] newTable)
      Transfer all entries from current table to newTable.
    • putAll

      public void putAll(Map<? extends K,? extends V> m)
      Copies all of the mappings from the specified map to this map These mappings will replace any mappings that this map had for any of the keys currently in the specified map.
      Specified by:
      putAll in interface Map<K,V>
      Overrides:
      putAll in class AbstractMap<K,V>
      Parameters:
      m - mappings to be stored in this map.
      Throws:
      NullPointerException - if the specified map is null.
    • remove

      public V remove(Object key)
      Removes the mapping for this key from this map if present.
      Specified by:
      remove in interface Map<K,V>
      Overrides:
      remove in class AbstractMap<K,V>
      Parameters:
      key - key whose mapping is to be removed from the map.
      Returns:
      previous value associated with specified key, or null if there was no mapping for key. A null return can also indicate that the map previously associated null with the specified key.
    • removeEntryForKey

      KeyComparatorHashMap.Entry<K,V> removeEntryForKey(Object key)
      Removes and returns the entry associated with the specified key in the HashMap. Returns null if the HashMap contains no mapping for this key.
    • removeMapping

      KeyComparatorHashMap.Entry<K,V> removeMapping(Object o)
      Special version of remove for EntrySet.
    • clear

      public void clear()
      Removes all mappings from this map.
      Specified by:
      clear in interface Map<K,V>
      Overrides:
      clear in class AbstractMap<K,V>
    • containsValue

      public boolean containsValue(Object value)
      Returns true if this map maps one or more keys to the specified value.
      Specified by:
      containsValue in interface Map<K,V>
      Overrides:
      containsValue in class AbstractMap<K,V>
      Parameters:
      value - value whose presence in this map is to be tested.
      Returns:
      true if this map maps one or more keys to the specified value.
    • containsNullValue

      private boolean containsNullValue()
      Special-case code for containsValue with null argument
    • clone

      public Object clone()
      Returns a shallow copy of this HashMap instance: the keys and values themselves are not cloned.
      Overrides:
      clone in class AbstractMap<K,V>
      Returns:
      a shallow copy of this map.
    • addEntry

      void addEntry(int hash, K key, V value, int bucketIndex)
      Add a new entry with the specified key, value and hash code to the specified bucket. It is the responsibility of this method to resize the table if appropriate.

      Subclass overrides this to alter the behavior of put method.

    • createEntry

      void createEntry(int hash, K key, V value, int bucketIndex)
      Like addEntry except that this version is used when creating entries as part of Map construction or "pseudo-construction" (cloning, deserialization). This version needn't worry about resizing the table.

      Subclass overrides this to alter the behavior of HashMap(Map), clone, and readObject.

    • newKeyIterator

      Iterator<K> newKeyIterator()
    • newValueIterator

      Iterator<V> newValueIterator()
    • newEntryIterator

      Iterator<Map.Entry<K,V>> newEntryIterator()
    • entrySet

      public Set<Map.Entry<K,V>> entrySet()
      Returns a collection view of the mappings contained in this map. Each element in the returned collection is a Map.Entry. The collection is backed by the map, so changes to the map are reflected in the collection, and vice-versa. The collection supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Collection.remove, removeAll, retainAll, and clear operations. It does not support the add or addAll operations.
      Specified by:
      entrySet in interface Map<K,V>
      Specified by:
      entrySet in class AbstractMap<K,V>
      Returns:
      a collection view of the mappings contained in this map.
    • writeObject

      private void writeObject(ObjectOutputStream s) throws IOException
      Save the state of the HashMap instance to a stream (i.e., serialize it).
      Throws:
      IOException
    • readObject

      private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException
      Reconstitute the HashMap instance from a stream (i.e., deserialize it).
      Throws:
      IOException
      ClassNotFoundException
    • capacity

      int capacity()
    • loadFactor

      float loadFactor()