LocalMap (Javolution 5.5.1 API)

java.lang.Object
- _templates.javolution.util.LocalMap

All Implemented Interfaces:

Map
```
public final class LocalMap
extends Object
implements Map
```
This class represents a map which can be temporarily modified without impacting other threads (scoped changes).

Operation on instances of this class are thread-safe. For example: public class XMLFormat { static LocalMap CLASS_TO_FORMAT = new LocalMap(); public static void setFormat(Class forClass, XMLFormat that) { CLASS_TO_FORMAT.put(forClass, that); // No synchronization required. } public static XMLFormat getInstance(Class forClass) { return CLASS_TO_FORMAT.get(forClass); // No synchronization required. } } public void main(String[] args) { // Sets default (global settings). XMLFormat.setFormat(Foo.class, xFormat); XMLFormat.setFormat(Bar.class, yFormat); } ... // Another thread. LocalContext.enter(); try { // Use of local context to avoid impacting other threads. XMLFormat.setFormat(Foo.class, zFormat); XMLFormat.getInstance(Foo.class); // Returns zFormat XMLFormat.getInstance(Bar.class); // Returns yFormat (inherited) } finally { LocalContext.exit(); } getInstance(Foo.class); // Returns xFormat [/code]

Note: Because key-value mappings are inherited, the semantic of remove(java.lang.Object) and clear() is slightly modified (association with null values instead of removing the entries).

Version:

3.7, January 27, 2005

Author:

Jean-Marie Dautelle

Nested Class Summary
- Nested classes/interfaces inherited from interface _templates.java.util.Map
  Map.Entry

Constructor Summary

Constructors
Constructor and Description

LocalMap()
Default constructor.

Constructors
Constructor and Description
`LocalMap()` Default constructor.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`clear()` Removes all mappings from this map (sets the local values to `null`).
`boolean`	`containsKey(Object key)` Indicates if this map contains a mapping for the specified key.
`boolean`	`containsValue(Object value)` Indicates if this map associates one or more keys to the specified value.
`Set`	`entrySet()` Returns a `FastCollection` view of the mappings contained in this map.
`Object`	`get(Object key)` Returns the value to which this map associates the specified key.
`Object`	`getDefault(Object key)` Returns the default value for the specified key.
`boolean`	`isEmpty()` Indicates if this map contains no key-value mappings.
`Set`	`keySet()` Returns a `FastCollection` view of the keys contained in this map.
`Object`	`put(Object key, Object value)` Associates the specified value with the specified key in this map.
`void`	`putAll(Map map)` Copies all of the mappings from the specified map to this map.
`Object`	`putDefault(Object key, Object defaultValue)` Sets the default value for the specified key (typically done at initialization).
`Object`	`remove(Object key)` Removes the mapping for this key from this map if present (sets the local value to `null`).
`LocalMap`	`setKeyComparator(FastComparator keyComparator)` Sets the key comparator for this local map.
`LocalMap`	`setValueComparator(FastComparator valueComparator)` Sets the value comparator for this local map.
`int`	`size()` Returns the number of key-value mappings in this map.
`Collection`	`values()` Returns a `FastCollection` view of the values contained in this map.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface _templates.java.util.Map
equals, hashCode

- Constructor Detail
  - LocalMap
```
public LocalMap()
```
    Default constructor.
- Method Detail
  - setKeyComparator
```
public LocalMap setKeyComparator(FastComparator keyComparator)
```
    Sets the key comparator for this local map.
    
    Parameters:
    
    keyComparator - the key comparator.
    
    Returns:
    
    this
  - setValueComparator
```
public LocalMap setValueComparator(FastComparator valueComparator)
```
    Sets the value comparator for this local map.
    
    Parameters:
    
    valueComparator - the value comparator.
    
    Returns:
    
    this
  - putDefault
```
public Object putDefault(Object key,
                         Object defaultValue)
```
    Sets the default value for the specified key (typically done at initialization).
    
    Parameters:
    
    key - the key with which the specified value is to be associated.
    
    defaultValue - the default value to be associated with the specified key.
    
    Returns:
    
    the previous default value associated with specified key, or null if there was no mapping for key. A null return can also indicate that the map previously associated null with the specified key.
    
    Throws:
    
    NullPointerException - if the key is null.
  - getDefault
```
public Object getDefault(Object key)
```
    Returns the default value for the specified key.
    
    Parameters:
    
    key - the key with which the default value is associated.
    
    Returns:
    
    the default value associated with specified key, or null if there was no mapping for the key.
    
    Throws:
    
    NullPointerException - if the key is null.
  - size
```
public int size()
```
    Returns the number of key-value mappings in this map.
    
    Specified by:
    
    size in interface Map
    
    Returns:
    
    this map's size.
  - isEmpty
```
public boolean isEmpty()
```
    Indicates if this map contains no key-value mappings.
    
    Specified by:
    
    isEmpty in interface Map
    
    Returns:
    
    true if this map contains no key-value mappings; false otherwise.
  - containsKey
```
public boolean containsKey(Object key)
```
    Indicates if this map contains a mapping for the specified key.
    
    Specified by:
    
    containsKey in interface Map
    
    Parameters:
    
    key - the key whose presence in this map is to be tested.
    
    Returns:
    
    true if this map contains a mapping for the specified key; false otherwise.
    
    Throws:
    
    NullPointerException - if the key is null.
  - containsValue
```
public boolean containsValue(Object value)
```
    Indicates if this map associates one or more keys to the specified value.
    
    Specified by:
    
    containsValue in interface Map
    
    Parameters:
    
    value - the value whose presence in this map is to be tested.
    
    Returns:
    
    true if this map maps one or more keys to the specified value.
    
    Throws:
    
    NullPointerException - if the key is null.
  - get
```
public Object get(Object key)
```
    Returns the value to which this map associates the specified key.
    
    Specified by:
    
    get in interface Map
    
    Parameters:
    
    key - the key whose associated value is to be returned.
    
    Returns:
    
    the value to which this map maps the specified key, or null if there is no mapping for the key.
    
    Throws:
    
    NullPointerException - if key is null.
  - put
```
public Object put(Object key,
                  Object value)
```
    Associates the specified value with the specified key in this map.
    
    Specified by:
    
    put in interface Map
    
    Parameters:
    
    key - the key with which the specified value is to be associated.
    
    value - the value to be associated with the specified key.
    
    Returns:
    
    the previous value associated with specified key, or null if there was no mapping for key. A null return can also indicate that the map previously associated null with the specified key.
    
    Throws:
    
    NullPointerException - if the key is null.
  - putAll
```
public void putAll(Map map)
```
    Copies all of the mappings from the specified map to this map.
    
    Specified by:
    
    putAll in interface Map
    
    Parameters:
    
    map - the mappings to be stored in this map.
    
    Throws:
    
    NullPointerException - the specified map is null, or the specified map contains null keys.
  - remove
```
public Object remove(Object key)
```
    Removes the mapping for this key from this map if present (sets the local value to null).
    
    Specified by:
    
    remove in interface Map
    
    Parameters:
    
    key - the key whose value is set to null
    
    Returns:
    
    put(key, null)
    
    Throws:
    
    NullPointerException - if the key is null.
  - clear
```
public void clear()
```
    Removes all mappings from this map (sets the local values to null).
    
    Specified by:
    
    clear in interface Map
  - keySet
```
public Set keySet()
```
    Returns a FastCollection view of the keys contained in this map.
    
    Specified by:
    
    keySet in interface Map
    
    Returns:
    
    a set view of the keys contained in this map (instance of FastCollection).
  - values
```
public Collection values()
```
    Returns a FastCollection view of the values contained in this map.
    
    Specified by:
    
    values in interface Map
    
    Returns:
    
    a collection view of the values contained in this map (instance of FastCollection).
  - entrySet
```
public Set entrySet()
```
    Returns a FastCollection view of the mappings contained in this map.
    
    Specified by:
    
    entrySet in interface Map
    
    Returns:
    
    a collection view of the mappings contained in this map (instance of FastCollection).

Class LocalMap

Nested Class Summary

Nested classes/interfaces inherited from interface _templates.java.util.Map

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface _templates.java.util.Map

Constructor Detail

LocalMap

Method Detail

setKeyComparator

setValueComparator

putDefault

getDefault

size

isEmpty

containsKey

containsValue

get

put

putAll

remove

clear

keySet

values

entrySet