Class HashTrieMap

java.lang.Object
net.sf.saxon.ma.map.MapItem
net.sf.saxon.ma.map.HashTrieMap
All Implemented Interfaces:
Callable, FunctionItem, GroundedValue, Item, Sequence

public class HashTrieMap extends MapItem
An immutable map. This implementation, which uses a hash trie, was introduced in Saxon 9.6
  • Constructor Details

    • HashTrieMap

      public HashTrieMap()
      Create an empty map
    • HashTrieMap

      public HashTrieMap(ImmutableMap<AtomicMatchKey,KeyValuePair> imap)
      Create a map whose contents are a copy of an existing immutable map
      Parameters:
      imap - the map to be copied
  • Method Details

    • singleton

      public static HashTrieMap singleton(AtomicValue key, GroundedValue value)
      Create a singleton map with a single key and value
      Parameters:
      key - the key value
      value - the associated value
      Returns:
      a singleton map
    • copy

      public static HashTrieMap copy(MapItem map)
      Create a map whose entries are copies of the entries in an existing MapItem
      Parameters:
      map - the existing map to be copied
      Returns:
      the new map
    • size

      public int size()
      Get the size of the map
      Specified by:
      size in class MapItem
      Returns:
      the number of keys/entries present in this map
    • isEmpty

      public boolean isEmpty()
      Ask whether the map is empty
      Overrides:
      isEmpty in class MapItem
      Returns:
      true if and only if the size of the map is zero
    • conforms

      public boolean conforms(PlainType requiredKeyType, SequenceType requiredValueType, TypeHierarchy th)
      Ask whether the map conforms to a given map type
      Specified by:
      conforms in class MapItem
      Parameters:
      requiredKeyType - the required keyType
      requiredValueType - the required valueType
      th - the type hierarchy cache for the configuration
      Returns:
      true if the map conforms to the required type
    • getItemType

      public MapType getItemType(TypeHierarchy th)
      Get the type of the map. This method is used largely for diagnostics, to report the type of a map when it differs from the required type. This method has the side-effect of updating the internal type information held within the map.
      Specified by:
      getItemType in class MapItem
      Parameters:
      th - The type hierarchy cache for the configuration
      Returns:
      the type of this map
    • getKeyUType

      public UType getKeyUType()
      Get the lowest common item type of the keys in the map
      Specified by:
      getKeyUType in class MapItem
      Returns:
      the most specific type to which all the keys belong. If the map is empty, return UType.VOID (the type with no instances)
    • addEntry

      public HashTrieMap addEntry(AtomicValue key, GroundedValue value)
      Create a new map containing the existing entries in the map plus an additional entry, without modifying the original. If there is already an entry with the specified key, this entry is replaced by the new entry.
      Specified by:
      addEntry in class MapItem
      Parameters:
      key - the key of the new entry
      value - the value associated with the new entry
      Returns:
      the new map containing the additional entry
    • initialPut

      public boolean initialPut(AtomicValue key, GroundedValue value)
      Add a new entry to this map. Since the map is supposed to be immutable, this method must only be called while initially populating the map, and must not be called if anyone else might already be using the map.
      Parameters:
      key - the key of the new entry. Any existing entry with this key is replaced.
      value - the value associated with the new entry
      Returns:
      true if an existing entry with the same key was replaced
    • remove

      public HashTrieMap remove(AtomicValue key)
      Remove an entry from the map
      Specified by:
      remove in class MapItem
      Parameters:
      key - the key of the entry to be removed
      Returns:
      a new map in which the requested entry has been removed; or this map unchanged if the specified key was not present
    • get

      public GroundedValue get(AtomicValue key)
      Get an entry from the Map
      Specified by:
      get in class MapItem
      Parameters:
      key - the value of the key
      Returns:
      the value associated with the given key, or null if the key is not present in the map
    • getKeyValuePair

      public KeyValuePair getKeyValuePair(AtomicValue key)
      Get an key/value pair from the Map
      Parameters:
      key - the value of the key
      Returns:
      the key-value-pair associated with the given key, or null if the key is not present in the map
    • keys

      public AtomicIterator keys()
      Get the set of all key values in the map
      Specified by:
      keys in class MapItem
      Returns:
      an iterator over the keys, in undefined order
    • keyValuePairs

      public Iterable<KeyValuePair> keyValuePairs()
      Get the set of all key-value pairs in the map
      Specified by:
      keyValuePairs in class MapItem
      Returns:
      an iterator over the key-value pairs
    • diagnosticDump

      public void diagnosticDump()
    • toString

      public String toString()
      Overrides:
      toString in class Object