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 *      http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.commons.collections.collection;

import java.util.Collection;
import java.util.Iterator;

Decorates another Collection to provide additional behaviour.

Each method call made on this Collection is forwarded to the decorated Collection. This class is used as a framework on which to build to extensions such as synchronized and unmodifiable behaviour. The main advantage of decoration is that one decorator can wrap any implementation of Collection, whereas sub-classing requires a new class to be written for each implementation.

This implementation does not perform any special processing with iterator(). Instead it simply returns the value from the wrapped collection. This may be undesirable, for example if you are trying to write an unmodifiable implementation it might provide a loophole.

Author:Stephen Colebourne, Paul Jack
Since:Commons Collections 3.0
Version:$Revision: 646777 $ $Date: 2008-04-10 14:33:15 +0200 (Thu, 10 Apr 2008) $
/** * Decorates another <code>Collection</code> to provide additional behaviour. * <p> * Each method call made on this <code>Collection</code> is forwarded to the * decorated <code>Collection</code>. This class is used as a framework on which * to build to extensions such as synchronized and unmodifiable behaviour. The * main advantage of decoration is that one decorator can wrap any implementation * of <code>Collection</code>, whereas sub-classing requires a new class to be * written for each implementation. * <p> * This implementation does not perform any special processing with * {@link #iterator()}. Instead it simply returns the value from the * wrapped collection. This may be undesirable, for example if you are trying * to write an unmodifiable implementation it might provide a loophole. * * @since Commons Collections 3.0 * @version $Revision: 646777 $ $Date: 2008-04-10 14:33:15 +0200 (Thu, 10 Apr 2008) $ * * @author Stephen Colebourne * @author Paul Jack */
public abstract class AbstractCollectionDecorator implements Collection {
The collection being decorated
/** The collection being decorated */
protected Collection collection;
Constructor only used in deserialization, do not use otherwise.
Since:Commons Collections 3.1
/** * Constructor only used in deserialization, do not use otherwise. * @since Commons Collections 3.1 */
protected AbstractCollectionDecorator() { super(); }
Constructor that wraps (not copies).
Params:
  • coll – the collection to decorate, must not be null
Throws:
/** * Constructor that wraps (not copies). * * @param coll the collection to decorate, must not be null * @throws IllegalArgumentException if the collection is null */
protected AbstractCollectionDecorator(Collection coll) { if (coll == null) { throw new IllegalArgumentException("Collection must not be null"); } this.collection = coll; }
Gets the collection being decorated.
Returns:the decorated collection
/** * Gets the collection being decorated. * * @return the decorated collection */
protected Collection getCollection() { return collection; } //----------------------------------------------------------------------- public boolean add(Object object) { return collection.add(object); } public boolean addAll(Collection coll) { return collection.addAll(coll); } public void clear() { collection.clear(); } public boolean contains(Object object) { return collection.contains(object); } public boolean isEmpty() { return collection.isEmpty(); } public Iterator iterator() { return collection.iterator(); } public boolean remove(Object object) { return collection.remove(object); } public int size() { return collection.size(); } public Object[] toArray() { return collection.toArray(); } public Object[] toArray(Object[] object) { return collection.toArray(object); } public boolean containsAll(Collection coll) { return collection.containsAll(coll); } public boolean removeAll(Collection coll) { return collection.removeAll(coll); } public boolean retainAll(Collection coll) { return collection.retainAll(coll); } public boolean equals(Object object) { if (object == this) { return true; } return collection.equals(object); } public int hashCode() { return collection.hashCode(); } public String toString() { return collection.toString(); } }