# Class: LocalMap

## vertx-js/local_map~ LocalMap

#### new LocalMap()

  Local maps can be used to share data safely in a single Vert.x instance.

  Source:
    - local_map.js, line 29

### Methods

#### clear()

  Clear all entries in the map
  Source:
    - local_map.js, line 83

#### close()

  Close and release the map
  Source:
    - local_map.js, line 185

#### get(key) → {Object}

  Get a value from the map

  ##### Parameters:

  Name | Type | Description
  --- | --- | ---
  `key` | Object | the key

  Source:
    - local_map.js, line 41

  ##### Returns:

  the value, or null if none
  Type
    Object

#### isEmpty() → {boolean}

  Source:
    - local_map.js, line 111

  ##### Returns:

  - true if there are zero entries in the map
  - Type
      boolean

#### put(key, value) → {Object}

  Put an entry in the map

  ##### Parameters:

  Name | Type | Description
  --- | --- | ---
  `key` | Object | the key
  `value` | Object | the value

  Source:
    - local_map.js, line 56

  ##### Returns:

  return the old value, or null if none
  Type
    Object

#### putIfAbsent(key, value) → {Object}

  Put the entry only if there is no existing entry for that key

  ##### Parameters:

  Name | Type | Description
  --- | --- | ---
  `key` | Object | the key
  `value` | Object | the value

  Source:
    - local_map.js, line 126

  ##### Returns:

  the old value or null, if none
  Type
    Object

#### remove(key) → {Object}

  Remove an entry from the map

  ##### Parameters:

  Name | Type | Description
  --- | --- | ---
  `key` | Object | the key

  Source:
    - local_map.js, line 70

  ##### Returns:

  the old value
  Type
    Object

#### removeIfPresent(key, value) → {boolean}

  Remove the entry only if there is an entry with the specified key and value

  ##### Parameters:

  Name | Type | Description
  --- | --- | ---
  `key` | Object | the key
  `value` | Object | the value

  Source:
    - local_map.js, line 141

  ##### Returns:

  true if removed
  Type
    boolean

#### replace(key, value) → {Object}

  Replace the entry only if there is an existing entry with the key

  ##### Parameters:

  Name | Type | Description
  --- | --- | ---
  `key` | Object | the key
  `value` | Object | the new value

  Source:
    - local_map.js, line 172

  ##### Returns:

  the old value
  Type
    Object

#### replaceIfPresent(key, oldValue, newValue) → {boolean}

  Replace the entry only if there is an existing entry with the specified key and value

  ##### Parameters:

  Name | Type | Description
  --- | --- | ---
  `key` | Object | the key
  `oldValue` | Object | the old value
  `newValue` | Object | the new value

  Source:
    - local_map.js, line 157

  ##### Returns:

  true if removed
  Type
    boolean

#### size() → {number}

  Get the size of the map
  Source:
    - local_map.js, line 97

  ##### Returns:

  the number of entries in the map
  Type
    number