Module flare.commons
Package flare.commons

Class WeakIdentityHashMap<K,V>

java.lang.Object
java.util.AbstractMap<K,V>
flare.commons.WeakIdentityHashMap<K,V>
All Implemented Interfaces:
Map<K,V>
public class WeakIdentityHashMap<K,V> extends AbstractMap<K,V> implements Map<K,V>

  • Constructor Details

    • WeakIdentityHashMap

      public WeakIdentityHashMap(int initialCapacity, float loadFactor)
      Constructs a new, empty WeakIdentityHashMap with the given initial capacity and the given load factor.
      Parameters:
      initialCapacity - The initial capacity of the WeakIdentityHashMap
      loadFactor - The load factor of the WeakIdentityHashMap
      Throws:
      IllegalArgumentException - if the initial capacity is negative, or if the load factor is nonpositive.

    • WeakIdentityHashMap

      public WeakIdentityHashMap(int initialCapacity)
      Constructs a new, empty WeakIdentityHashMap with the given initial capacity and the default load factor (0.75).
      Parameters:
      initialCapacity - The initial capacity of the WeakIdentityHashMap
      Throws:
      IllegalArgumentException - if the initial capacity is negative

    • WeakIdentityHashMap

      public WeakIdentityHashMap()
      Constructs a new, empty WeakIdentityHashMap with the default initial capacity (16) and load factor (0.75).

    • WeakIdentityHashMap

      public WeakIdentityHashMap(Map<? extends K,? extends V> m)
      Constructs a new WeakIdentityHashMap with the same mappings as the specified map. The WeakIdentityHashMap is created with the 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
      Throws:
      NullPointerException - if the specified map is null
      Since:
      1.3

  • Method Details

    • size

      public int size()
      Returns the number of key-value mappings in this map. This result is a snapshot, and may not reflect unprocessed entries that will be removed before next attempted access because they are no longer referenced.
      Specified by:
      size in interface Map<K,V>
      Overrides:
      size in class AbstractMap<K,V>

    • isEmpty

      public boolean isEmpty()
      Returns true if this map contains no key-value mappings. This result is a snapshot, and may not reflect unprocessed entries that will be removed before next attempted access because they are no longer referenced.
      Specified by:
      isEmpty in interface Map<K,V>
      Overrides:
      isEmpty in class AbstractMap<K,V>

    • get

      public V get(Object key)
      Returns the value to which the specified key is mapped, or null if this map contains no mapping for the key.

      More formally, if this map contains a mapping from a key k to a value v such that (key==null ? k==null : key.equals(k)), then this method returns v; otherwise it returns null. (There can be at most one such mapping.)

      A return value of null does not necessarily indicate that the map contains no mapping for the key; it's also possible that the map explicitly maps the key to null. The containsKey operation may be used to distinguish these two cases.

      Specified by:
      get in interface Map<K,V>
      Overrides:
      get in class AbstractMap<K,V>
      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 there is a mapping for key; false otherwise

    • 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:
      the previous value associated with key, or null if there was no mapping for key. (A null return can also indicate that the map previously associated null with key.)

    • 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 a key from this weak hash map if it is present. More formally, if this map contains a mapping from key k to value v such that (key==null ? k==null : key.equals(k)), that mapping is removed. (The map can contain at most one such mapping.)

      Returns the value to which this map previously associated the key, or null if the map contained no mapping for the key. A return value of null does not necessarily indicate that the map contained no mapping for the key; it's also possible that the map explicitly mapped the key to null.

      The map will not contain a mapping for the specified key once the call returns.

      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:
      the previous value associated with key, or null if there was no mapping for key

    • clear

      public void clear()
      Removes all of the mappings from this map. The map will be empty after this call returns.
      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

    • keySet

      public Set<K> keySet()
      Returns a Set view of the keys contained in this map. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. If the map is modified while an iteration over the set is in progress (except through the iterator's own remove operation), the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Set.remove, removeAll, retainAll, and clear operations. It does not support the add or addAll operations.
      Specified by:
      keySet in interface Map<K,V>
      Overrides:
      keySet in class AbstractMap<K,V>

    • values

      public Collection<V> values()
      Returns a Collection view of the values contained in this map. The collection is backed by the map, so changes to the map are reflected in the collection, and vice-versa. If the map is modified while an iteration over the collection is in progress (except through the iterator's own remove operation), the results of the iteration are undefined. 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:
      values in interface Map<K,V>
      Overrides:
      values in class AbstractMap<K,V>

    • entrySet

      public Set<Map.Entry<K,V>> entrySet()
      Returns a Set view of the mappings contained in this map. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. If the map is modified while an iteration over the set is in progress (except through the iterator's own remove operation, or through the setValue operation on a map entry returned by the iterator) the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Set.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>

    • forEach

      public void forEach(BiConsumer<? super K,? super V> action)
      Specified by:
      forEach in interface Map<K,V>

    • replaceAll

      public void replaceAll(BiFunction<? super K,? super V,? extends V> function)
      Specified by:
      replaceAll in interface Map<K,V>