Java tutorial
/* * $Id$ * * License Agreement. * * Rich Faces - Natural Ajax for Java Server Faces (JSF) * * Copyright (C) 2007 Exadel, Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License version 2.1 as published by the Free Software Foundation. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ package org.richfaces.cdk.model; import java.io.Serializable; import java.util.Collection; import java.util.Collections; import java.util.Comparator; import java.util.Iterator; import java.util.List; import java.util.NoSuchElementException; import java.util.Set; import com.google.common.base.Predicate; import com.google.common.collect.Iterables; import com.google.common.collect.Iterators; import com.google.common.collect.Lists; /** * <p class="changed_added_4_0"> * Base class for all model collections. This collection use {@link Mergeable#same(Object)} method instead of equals to lookup * objects in the {@link #contains(Object)} and {@link #remove(Object)} methods. In addition, it merges same objects instead of * replace in the {@link #add(ModelElement)} method. * </p> * * @author asmirnov@exadel.com */ public class ModelSet<E extends ModelElement<? super E>> implements ModelCollection<E>, Set<E>, Serializable { private static final long serialVersionUID = -1L; private final List<E> elements = Lists.newArrayList(); private Comparator<E> comparator; public static <T extends ModelElement<? super T>> ModelSet<T> create() { return new ModelSet<T>(); } public static <T extends ModelElement<? super T>> ModelSet<T> create(Comparator<T> comparator) { ModelSet<T> collection = new ModelSet<T>(); collection.setComparator(comparator); return collection; } /** * <p class="changed_added_4_0"> * </p> * * @return the comparator */ public Comparator<E> getComparator() { return this.comparator; } /** * <p class="changed_added_4_0"> * </p> * * @param comparator the comparator to set */ public void setComparator(Comparator<E> comparator) { this.comparator = comparator; } @Override public E find(final Predicate<? super E> predicate) { try { return Iterables.find(elements, predicate); } catch (NoSuchElementException e) { return null; } } @Override public boolean add(E e) { if (null == e) { throw new NullPointerException(); } for (E element : elements) { if (element.same(e)) { element.merge(e); return false; } } return elements.add(e); } @Override public boolean addAll(Collection<? extends E> c) { boolean changed = false; for (E e : c) { changed |= add(e); } return changed; } @Override public void clear() { elements.clear(); } @SuppressWarnings("unchecked") @Override public boolean contains(Object o) { if (null != o) { Class<? extends Object> clazz = o.getClass(); for (E element : elements) { if (clazz.isInstance(element) && element.same((E) o)) { return true; } } } return false; } @Override public boolean containsAll(Collection<?> c) { return elements.containsAll(c); } @Override public boolean isEmpty() { return elements.isEmpty(); } @Override public Iterator<E> iterator() { if (null == comparator) { return elements.iterator(); } else { List<E> list = Lists.newArrayList(elements); Collections.sort(list, comparator); return Iterators.unmodifiableIterator(list.iterator()); } } @Override public boolean remove(Object o) { if (null != o) { Class<? extends Object> clazz = o.getClass(); for (E element : elements) { if (clazz.isInstance(element) && element.same((E) o)) { elements.remove(element); return true; } } } return false; } @Override public boolean removeAll(Collection<?> c) { boolean changed = false; for (Object e : c) { changed |= remove(e); } return changed; } @Override public boolean retainAll(Collection<?> c) { return elements.retainAll(c); } @Override public int size() { return elements.size(); } @Override public Object[] toArray() { Object[] array = elements.toArray(); return array; } @Override public <T> T[] toArray(T[] a) { return elements.toArray(a); } @Override public <R, D> R accept(R result, Visitor<R, D> visitor, D data) { return null == result ? accept(visitor, data) : result; } public <R, D> R accept(Visitor<R, D> visitor, D data) { for (ModelElement element : elements) { R result = element.accept(visitor, data); if (null != result) { return result; } } return null; } }