Package net.sf.saxon.ma.map

## Class DictionaryMap

- java.lang.Object
- - net.sf.saxon.ma.map.DictionaryMap

- All Implemented Interfaces:
    `Callable`, `MapItem`, `Function`, `GroundedValue`, `Item`, `Sequence`

      public class DictionaryMap
      extends java.lang.Object
      implements MapItem

  A simple implementation of MapItem where the strings are keys, and modification is unlikely. This implementation is used in a number of cases where it can be determined that it is suitable, for example when parsing JSON input, or when creating a fixed map to use in an options argument.

- - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `DictionaryMap()` | Create an empty dictionary, to which entries can be added using `initialPut(String, GroundedValue)`, provided this is done before the map is exposed to the outside world.

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `MapItem` | `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 keyType, SequenceType valueType, TypeHierarchy th)` | Ask whether the map conforms to a given map type
    `GroundedValue` | `get​(AtomicValue key)` | Get an entry from the Map
    `ItemType` | `getItemType​(TypeHierarchy th)` | Get the type of the map.
    `UType` | `getKeyUType()` | Get the lowest common item type of the keys in the map
    `void` | `initialAppend​(java.lang.String key, GroundedValue value)` | During initial construction of the map, append a value to a possibly existing key-value pair
    `void` | `initialPut​(java.lang.String key, GroundedValue value)` | During initial construction of the map, add a key-value pair
    `boolean` | `isEmpty()` | Ask whether the map is empty
    `AtomicIterator<StringValue>` | `keys()` | Get the set of all key values in the map.
    `java.lang.Iterable<KeyValuePair>` | `keyValuePairs()` | Get the set of all key-value pairs in the map
    `MapItem` | `remove​(AtomicValue key)` | Remove an entry from the map
    `int` | `size()` | Get the size of the map

    - ### Methods inherited from class java.lang.Object

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

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

      `asIterable, concatenate, containsNode, materialize`

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

      `getLength, head, isStreamed, iterate, reduce, subsequence`

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

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

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

      `makeRepeatable`

- - ### Constructor Detail

    - #### DictionaryMap

          public DictionaryMap()

      Create an empty dictionary, to which entries can be added using `initialPut(String, GroundedValue)`, provided this is done before the map is exposed to the outside world.

  - ### Method Detail

    - #### initialPut

          public void initialPut​(java.lang.String key,
                                 GroundedValue value)

      During initial construction of the map, add a key-value pair

    - #### initialAppend

          public void initialAppend​(java.lang.String key,
                                    GroundedValue value)

      During initial construction of the map, append a value to a possibly existing key-value pair

    - #### 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.

    - #### 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

    - #### keys

          public AtomicIterator<StringValue> keys()

      Get the set of all key values in the map.
      Specified by:
        `keys` in interface `MapItem`
      Returns:
        a set containing all the key values present in the map, in unpredictable order

    - #### keyValuePairs

          public java.lang.Iterable<KeyValuePair> keyValuePairs()

      Get the set of all key-value pairs in the map
      Specified by:
        `keyValuePairs` in interface `MapItem`
      Returns:
        an iterable containing all the key-value pairs

    - #### addEntry

          public MapItem 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

    - #### remove

          public MapItem 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

    - #### conforms

          public boolean conforms​(AtomicType keyType,
                                  SequenceType valueType,
                                  TypeHierarchy th)

      Ask whether the map conforms to a given map type
      Specified by:
        `conforms` in interface `MapItem`
      Parameters:
        `keyType` - the required keyType
        `valueType` - the required valueType
        `th` - the type hierarchy cache for the configuration
      Returns:
        true if the map conforms to the required type

    - #### getItemType

          public ItemType 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.
      Specified by:
        `getItemType` in interface `MapItem`
      Parameters:
        `th` - the type hierarchy cache
      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