Package org.apache.commons.collections.map

Class UnmodifiableMap

java.lang.Object

org.apache.commons.collections.map.AbstractMapDecorator

org.apache.commons.collections.map.UnmodifiableMap

All Implemented Interfaces:

Serializable, Map, IterableMap, Unmodifiable

public final class UnmodifiableMap
extends AbstractMapDecorator
implements IterableMap, Unmodifiable, Serializable

Decorates another Map to ensure it can't be altered.

This class is Serializable from Commons Collections 3.1.

Since:

Commons Collections 3.0

Version:

$Revision: 646777 $ $Date: 2008-04-10 14:33:15 +0200 (Thu, 10 Apr 2008) $

See Also:

• Serialized Form

Nested Class Summary

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

Map.Entry<K,V>

Field Summary

Fields

Modifier and Type	Field	Description
private static final long	serialVersionUID	Serialization version

Fields inherited from class org.apache.commons.collections.map.AbstractMapDecorator

map

Constructor Summary

Constructors

Modifier	Constructor	Description
private	UnmodifiableMap(Map map)	Constructor that wraps (not copies).

Method Summary

Modifier and Type	Method	Description
void	clear()
static Map	decorate(Map map)	Factory method to create an unmodifiable map.
Set	entrySet()
Set	keySet()
MapIterator	mapIterator()	Obtains a MapIterator over the map.
Object	put(Object key, Object value)
void	putAll(Map mapToCopy)
private void	readObject(ObjectInputStream in)	Read the map in using a custom routine.
Object	remove(Object key)
Collection	values()
private void	writeObject(ObjectOutputStream out)	Write the map out using a custom routine.

Methods inherited from class org.apache.commons.collections.map.AbstractMapDecorator

containsKey, containsValue, equals, get, getMap, hashCode, isEmpty, size, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Map

compute, computeIfAbsent, computeIfPresent, containsKey, containsValue, equals, forEach, get, getOrDefault, hashCode, isEmpty, merge, putIfAbsent, remove, replace, replace, replaceAll, size

Field Details

serialVersionUID

private static final long serialVersionUID

Serialization version

See Also:

• Constant Field Values

Constructor Details

UnmodifiableMap

private UnmodifiableMap(Map map)

Constructor that wraps (not copies).

Parameters:

map - the map to decorate, must not be null

Throws:

IllegalArgumentException - if map is null

Method Details

decorate

public static Map decorate(Map map)

Factory method to create an unmodifiable map.

Parameters:

map - the map to decorate, must not be null

Throws:

IllegalArgumentException - if map is null

writeObject

private void writeObject(ObjectOutputStream out)
                  throws IOException

Write the map out using a custom routine.

Parameters:

out - the output stream

Throws:

IOException

Since:

Commons Collections 3.1

readObject

private void readObject(ObjectInputStream in)
                 throws IOException,
ClassNotFoundException

Read the map in using a custom routine.

Parameters:

in - the input stream

Throws:

IOException

ClassNotFoundException

Since:

Commons Collections 3.1

clear

public void clear()

Specified by:

clear in interface Map

Overrides:

clear in class AbstractMapDecorator

put

public Object put(Object key,
 Object value)

Specified by:

put in interface Map

Overrides:

put in class AbstractMapDecorator

putAll

public void putAll(Map mapToCopy)

Specified by:

putAll in interface Map

Overrides:

putAll in class AbstractMapDecorator

remove

public Object remove(Object key)

Specified by:

remove in interface Map

Overrides:

remove in class AbstractMapDecorator

mapIterator

public MapIterator mapIterator()

Description copied from interface: IterableMap

Obtains a MapIterator over the map.

A map iterator is an efficient way of iterating over maps. There is no need to access the entry set or cast to Map Entry objects.

 IterableMap map = new HashedMap();
 MapIterator it = map.mapIterator();
 while (it.hasNext()) {
   Object key = it.next();
   Object value = it.getValue();
   it.setValue("newValue");
 }
 

Specified by:

mapIterator in interface IterableMap

Returns:

a map iterator

entrySet

public Set entrySet()

Specified by:

entrySet in interface Map

Overrides:

entrySet in class AbstractMapDecorator

keySet

public Set keySet()

Specified by:

keySet in interface Map

Overrides:

keySet in class AbstractMapDecorator

values

public Collection values()

Specified by:

values in interface Map

Overrides:

values in class AbstractMapDecorator