net.sf.saxon.ma.map

Class HashTrieMap

java.lang.Object

net.sf.saxon.ma.map.HashTrieMap

All Implemented Interfaces:

Iterable<Function>, Callable, MapItem, Function, GroundedValue<Function>, Item<Function>, Sequence<Function>

public class HashTrieMap
extends Object
implements MapItem

An immutable map. This implementation, which uses a hash trie, was introduced in Saxon 9.6

Field Summary

Fields

Modifier and Type	Field and Description
static SequenceType	SINGLE_MAP_TYPE

Constructor Summary

Constructors

Constructor and Description
HashTrieMap() Create an empty map
HashTrieMap(ImmutableMap<AtomicMatchKey,KeyValuePair> imap) Create a map whose contents are a copy of an existing immutable map

Method Summary

Modifier and Type	Method and Description
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.
boolean	conforms(AtomicType requiredKeyType, SequenceType requiredValueType, TypeHierarchy th) Ask whether the map conforms to a given map type
static HashTrieMap	copy(MapItem map) Create a map whose entries are copies of the entries in an existing MapItem
void	diagnosticDump()
GroundedValue<?>	get(AtomicValue key) Get an entry from the Map
MapType	getItemType(TypeHierarchy th) Get the type of the map.
UType	getKeyUType() Get the lowest common item type of the keys in the map
KeyValuePair	getKeyValuePair(AtomicValue key) Get an key/value pair from the Map
boolean	initialPut(AtomicValue key, GroundedValue<?> value) Add a new entry to this map.
boolean	isEmpty() Ask whether the map is empty
AtomicIterator	keys() Get the set of all key values in the map
Iterable<KeyValuePair>	keyValuePairs() Get the set of all key-value pairs in the map
HashTrieMap	remove(AtomicValue key) Remove an entry from the map
static HashTrieMap	singleton(AtomicValue key, GroundedValue<?> value) Create a singleton map with a single key and value
int	size() Get the size of the map
String	toShortString() Provide a short string showing the contents of the item, suitable for use in error messages
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface net.sf.saxon.ma.map.MapItem

atomize, call, deepEquals, effectiveBooleanValue, export, getAnnotations, getArity, getDescription, getFunctionItemType, getFunctionName, getGenre, getItemTypeOfSequence, getOperandRoles, getStringValue, getStringValueCS, getTypedValue, isArray, isKnownToConform, isMap, isTrustedResultType, itemAt, makeNewContext, mapToString

Methods inherited from interface net.sf.saxon.om.Function

argumentArray

Methods inherited from interface net.sf.saxon.om.Item

getLength, head, isStreamed, iterate, iterator, reduce, subsequence, toGroundedValue

Methods inherited from interface net.sf.saxon.om.GroundedValue

asIterable, materialize

Methods inherited from interface net.sf.saxon.om.Sequence

makeRepeatable

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Detail

SINGLE_MAP_TYPE

public static final SequenceType SINGLE_MAP_TYPE

Constructor Detail

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 Detail

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 interface MapItem

Returns:

the number of keys/entries present in this map

isEmpty

public boolean isEmpty()

Ask whether the map is empty

Specified by:

isEmpty in interface MapItem

Returns:

true if and only if the size of the map is zero

conforms

public boolean conforms(AtomicType requiredKeyType,
                        SequenceType requiredValueType,
                        TypeHierarchy th)

Ask whether the map conforms to a given map type

Specified by:

conforms in interface 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 interface 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 interface 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 interface 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 interface 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 interface 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 interface 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 interface MapItem

Returns:

an iterator over the key-value pairs

diagnosticDump

public void diagnosticDump()

toShortString

public String toShortString()

Description copied from interface: MapItem

Provide a short string showing the contents of the item, suitable for use in error messages

Specified by:

toShortString in interface MapItem

Specified by:

toShortString in interface Function

Specified by:

toShortString in interface GroundedValue<Function>

Specified by:

toShortString in interface Item<Function>

Returns:

a depiction of the item suitable for use in error messages

toString

public String toString()

Overrides:

toString in class Object