org.apache.commons.collections.map
Class PredicatedMap

java.lang.Object
  |
  +--org.apache.commons.collections.map.AbstractMapDecorator
        |
        +--org.apache.commons.collections.map.AbstractInputCheckedMapDecorator
              |
              +--org.apache.commons.collections.map.PredicatedMap

All Implemented Interfaces:

Map, Serializable

Direct Known Subclasses:

PredicatedSortedMap

public class PredicatedMap

extends org.apache.commons.collections.map.AbstractInputCheckedMapDecorator

implements Serializable

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);

This class is Serializable from Commons Collections 3.1.

Since:

Commons Collections 3.0

Version:

$Revision: 1.14 $ $Date: 2004/06/07 22:14:42 $

Author:

Stephen Colebourne, Paul Jack

See Also:

Serialized Form

Field Summary

protected Predicate	keyPredicate The key predicate to use
protected Predicate	valuePredicate The value predicate to use

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

map

Constructor Summary

protected

PredicatedMap(Map map, Predicate keyPredicate, Predicate valuePredicate) Constructor that wraps (not copies).

Method Summary

protected Object	checkSetValue(Object value) Override to validate an object set into the map via setValue.
static Map	decorate(Map map, Predicate keyPredicate, Predicate valuePredicate) Factory method to create a predicated (validating) map.
Set	entrySet()
protected boolean	isSetValueChecking() Override to only return true when there is a value transformer.
Object	put(Object key, Object value)
void	putAll(Map mapToCopy)
protected void	validate(Object key, Object value) Validates a key value pair.

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

clear, containsKey, containsValue, equals, get, getMap, hashCode, isEmpty, keySet, remove, size, toString, values

Methods inherited from class java.lang.Object

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

Field Detail

keyPredicate

protected final Predicate keyPredicate

The key predicate to use

valuePredicate

protected final Predicate valuePredicate

The value predicate to use

Constructor Detail

PredicatedMap

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

Method Detail

decorate

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

validate

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

checkSetValue

protected Object checkSetValue(Object value)

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

Specified by:

checkSetValue in class org.apache.commons.collections.map.AbstractInputCheckedMapDecorator

Parameters:

value - the value to validate

Throws:

IllegalArgumentException - if invalid

Since:

Commons Collections 3.1

isSetValueChecking

protected boolean isSetValueChecking()

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

Overrides:

isSetValueChecking in class org.apache.commons.collections.map.AbstractInputCheckedMapDecorator

Returns:

true if a value predicate is in use

Since:

Commons Collections 3.1

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

entrySet

public Set entrySet()

Specified by:

entrySet in interface Map

Overrides:

entrySet in class AbstractMapDecorator