public class PredicatedCollection extends AbstractSerializableCollectionDecorator
Collection to validate that additions
match a specified predicate.
This collection exists to provide validation for the decorated collection. It is normally created to decorate an empty collection. If an object cannot be added to the collection, an IllegalArgumentException is thrown.
One usage would be to ensure that no null entries are added to the collection.
Collection coll = PredicatedCollection.decorate(new ArrayList(), NotNullPredicate.INSTANCE);
This class is Serializable from Commons Collections 3.1.
| Modifier and Type | Field and Description |
|---|---|
protected Predicate |
predicate
The predicate to use
|
collection| Modifier | Constructor and Description |
|---|---|
protected |
PredicatedCollection(Collection coll,
Predicate predicate)
Constructor that wraps (not copies).
|
| Modifier and Type | Method and Description |
|---|---|
boolean |
add(Object object)
Override to validate the object being added to ensure it matches
the predicate.
|
boolean |
addAll(Collection coll)
Override to validate the objects being added to ensure they match
the predicate.
|
static Collection |
decorate(Collection coll,
Predicate predicate)
Factory method to create a predicated (validating) collection.
|
protected void |
validate(Object object)
Validates the object being added to ensure it matches the predicate.
|
protected final Predicate predicate
protected PredicatedCollection(Collection coll, Predicate predicate)
If there are any elements already in the collection being decorated, they are validated.
coll - the collection to decorate, must not be nullpredicate - the predicate to use for validation, must not be nullIllegalArgumentException - if collection or predicate is nullIllegalArgumentException - if the collection contains invalid elementspublic static Collection decorate(Collection coll, Predicate predicate)
If there are any elements already in the collection being decorated, they are validated.
coll - the collection to decorate, must not be nullpredicate - the predicate to use for validation, must not be nullIllegalArgumentException - if collection or predicate is nullIllegalArgumentException - if the collection contains invalid elementsprotected void validate(Object object)
The predicate itself should not throw an exception, but return false to indicate that the object cannot be added.
object - the object being addedIllegalArgumentException - if the add is invalidpublic boolean add(Object object)
add in interface Collectionadd in class AbstractCollectionDecoratorobject - the object being addedIllegalArgumentException - if the add is invalidpublic boolean addAll(Collection coll)
addAll in interface CollectionaddAll in class AbstractCollectionDecoratorcoll - the collection being addedIllegalArgumentException - if the add is invalidCopyright © 2001–2015 The Apache Software Foundation. All rights reserved.