public class

PredicatedMap

extends AbstractMapDecorator
implements Serializable
java.lang.Object
   ↳ org.apache.commons.collections.map.AbstractMapDecorator
     ↳ org.apache.commons.collections.map.PredicatedMap
Known Direct Subclasses

Class Overview

Decorates another Map to validate that additions match a specified predicate.

This map exists to provide validation for the decorated map. It is normally created to decorate an empty map. If an object cannot be added to the map, an IllegalArgumentException is thrown.

One usage would be to ensure that no null keys are added to the map. 

Map map = PredicatedSet.decorate(new HashMap(), NotNullPredicate.INSTANCE, null);

Note that PredicatedMap is not synchronized and is not thread-safe. If you wish to use this map from multiple threads concurrently, you must use appropriate synchronization. The simplest approach is to wrap this map using synchronizedMap(Map). This class may throw exceptions when accessed by concurrent threads without synchronization.

This class is Serializable from Commons Collections 3.1.

Summary

Fields
protected final Predicate keyPredicate The key predicate to use
protected final Predicate valuePredicate The value predicate to use
[Expand]
Inherited Fields
From class org.apache.commons.collections.map.AbstractMapDecorator
Protected Constructors
PredicatedMap(Map map, Predicate keyPredicate, Predicate valuePredicate)
Constructor that wraps (not copies).
Public Methods
static Map decorate(Map map, Predicate keyPredicate, Predicate valuePredicate)
Factory method to create a predicated (validating) map.
Set entrySet()
Object put(Object key, Object value)
void putAll(Map mapToCopy)
Protected Methods
Object checkSetValue(Object value)
Override to validate an object set into the map via setValue.
boolean isSetValueChecking()
Override to only return true when there is a value transformer.
void validate(Object key, Object value)
Validates a key value pair.
[Expand]
Inherited Methods
From class org.apache.commons.collections.map.AbstractMapDecorator
From class java.lang.Object
From interface java.util.Map

Fields

protected final Predicate keyPredicate

The key predicate to use

protected final Predicate valuePredicate

The value predicate to use

Protected Constructors

protected PredicatedMap (Map map, Predicate keyPredicate, Predicate valuePredicate)

Constructor that wraps (not copies).

Parameters
map the map to decorate, must not be null
keyPredicate the predicate to validate the keys, null means no check
valuePredicate the predicate to validate to values, null means no check
Throws
IllegalArgumentException if the map is null

Public Methods

public static Map decorate (Map map, Predicate keyPredicate, Predicate valuePredicate)

Factory method to create a predicated (validating) map.

If there are any elements already in the list being decorated, they are validated.

Parameters
map the map to decorate, must not be null
keyPredicate the predicate to validate the keys, null means no check
valuePredicate the predicate to validate to values, null means no check
Throws
IllegalArgumentException if the map is null

public Set entrySet ()

public Object put (Object key, Object value)

public void putAll (Map mapToCopy)

Protected Methods

protected Object checkSetValue (Object value)

Override to validate an object set into the map via setValue.

Parameters
value the value to validate
Throws
IllegalArgumentException if invalid

protected boolean isSetValueChecking ()

Override to only return true when there is a value transformer.

Returns
  • true if a value predicate is in use

protected void validate (Object key, Object value)

Validates a key value pair.

Parameters
key the key to validate
value the value to validate
Throws
IllegalArgumentException if invalid