| /* |
| * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code 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 General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package com.sun.xml.internal.xsom.util; |
| |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.NoSuchElementException; |
| |
| /** |
| * {@link Collection} that returns the view of objects which are actually fetched |
| * lazily from an {@link Iterator}. |
| * |
| * @author Kohsuke Kawaguchi |
| */ |
| public class DeferedCollection<T> implements Collection<T> { |
| /** |
| * The iterator that lazily evaluates SCD query. |
| */ |
| private final Iterator<T> result; |
| |
| /** |
| * Stores values that are already fetched from {@link #result}. |
| */ |
| private final List<T> archive = new ArrayList<T>(); |
| |
| public DeferedCollection(Iterator<T> result) { |
| this.result = result; |
| } |
| |
| public boolean isEmpty() { |
| if(archive.isEmpty()) |
| fetch(); |
| return archive.isEmpty(); |
| } |
| |
| public int size() { |
| fetchAll(); |
| return archive.size(); |
| } |
| |
| public boolean contains(Object o) { |
| if(archive.contains(o)) |
| return true; |
| while(result.hasNext()) { |
| T value = result.next(); |
| archive.add(value); |
| if(value.equals(o)) |
| return true; |
| } |
| return false; |
| } |
| |
| public boolean containsAll(Collection<?> c) { |
| for (Object o : c) { |
| if(!contains(o)) |
| return false; |
| } |
| return true; |
| } |
| |
| public Iterator<T> iterator() { |
| return new Iterator<T>() { |
| int idx=0; |
| public boolean hasNext() { |
| if(idx<archive.size()) |
| return true; |
| return result.hasNext(); |
| } |
| |
| public T next() { |
| if(idx==archive.size()) |
| fetch(); |
| if(idx==archive.size()) |
| throw new NoSuchElementException(); |
| return archive.get(idx++); |
| } |
| |
| public void remove() { |
| // TODO |
| } |
| }; |
| } |
| |
| public Object[] toArray() { |
| fetchAll(); |
| return archive.toArray(); |
| } |
| |
| public <T>T[] toArray(T[] a) { |
| fetchAll(); |
| return archive.toArray(a); |
| } |
| |
| |
| |
| private void fetchAll() { |
| while(result.hasNext()) |
| archive.add(result.next()); |
| } |
| |
| /** |
| * Fetches another item from {@link |
| */ |
| private void fetch() { |
| if(result.hasNext()) |
| archive.add(result.next()); |
| } |
| |
| // mutation methods are unsupported |
| public boolean add(T o) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| public boolean remove(Object o) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| public boolean addAll(Collection<? extends T> c) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| public boolean removeAll(Collection<?> c) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| public boolean retainAll(Collection<?> c) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| public void clear() { |
| throw new UnsupportedOperationException(); |
| } |
| } |