org.apache.commons.collections.buffer
Class PredicatedBuffer

java.lang.Object
  org.apache.commons.collections.collection.AbstractCollectionDecorator
      org.apache.commons.collections.collection.AbstractSerializableCollectionDecorator
          org.apache.commons.collections.collection.PredicatedCollection
              org.apache.commons.collections.buffer.PredicatedBuffer

All Implemented Interfaces:

java.io.Serializable, java.lang.Iterable, java.util.Collection, Buffer

public class PredicatedBuffer
extends PredicatedCollection
implements Buffer

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

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

One usage would be to ensure that no null entries are added to the buffer.

Buffer buffer = PredicatedBuffer.decorate(new UnboundedFifoBuffer(), NotNullPredicate.INSTANCE);

This class is Serializable from Commons Collections 3.1.

Since:

Commons Collections 3.0

Version:

$Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $

Author:

Stephen Colebourne, Paul Jack

See Also:

Serialized Form

Field Summary

Fields inherited from class org.apache.commons.collections.collection.PredicatedCollection

predicate

Fields inherited from class org.apache.commons.collections.collection.AbstractCollectionDecorator

collection

Constructor Summary

protected

PredicatedBuffer(Buffer buffer, Predicate predicate) Constructor that wraps (not copies).

Method Summary

static Buffer	decorate(Buffer buffer, Predicate predicate) Factory method to create a predicated (validating) buffer.
java.lang.Object	get() Gets the next object from the buffer without removing it.
protected Buffer	getBuffer() Gets the buffer being decorated.
java.lang.Object	remove() Gets and removes the next object from the buffer.

Methods inherited from class org.apache.commons.collections.collection.PredicatedCollection

add, addAll, decorate, validate

Methods inherited from class org.apache.commons.collections.collection.AbstractCollectionDecorator

clear, contains, containsAll, equals, getCollection, hashCode, isEmpty, iterator, remove, removeAll, retainAll, size, toArray, toArray, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Collection

add, addAll, clear, contains, containsAll, equals, hashCode, isEmpty, iterator, remove, removeAll, retainAll, size, toArray, toArray

Constructor Detail

PredicatedBuffer

protected PredicatedBuffer(Buffer buffer,
                           Predicate predicate)

Constructor that wraps (not copies).

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

Parameters:

buffer - the buffer to decorate, must not be null

predicate - the predicate to use for validation, must not be null

Throws:

java.lang.IllegalArgumentException - if buffer or predicate is null

java.lang.IllegalArgumentException - if the buffer contains invalid elements

Method Detail

decorate

public static Buffer decorate(Buffer buffer,
                              Predicate predicate)

Factory method to create a predicated (validating) buffer.

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

Parameters:

buffer - the buffer to decorate, must not be null

predicate - the predicate to use for validation, must not be null

Returns:

a new predicated Buffer

Throws:

java.lang.IllegalArgumentException - if buffer or predicate is null

java.lang.IllegalArgumentException - if the buffer contains invalid elements

getBuffer

protected Buffer getBuffer()

Gets the buffer being decorated.

Returns:

the decorated buffer

get

public java.lang.Object get()

Description copied from interface: Buffer

Gets the next object from the buffer without removing it.

Specified by:

get in interface Buffer

Returns:

the next object in the buffer, which is not removed

remove

public java.lang.Object remove()

Description copied from interface: Buffer

Gets and removes the next object from the buffer.

Specified by:

remove in interface Buffer

Returns:

the next object in the buffer, which is also removed