| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.apache.openjpa.lib.rop; |
| |
| import java.util.AbstractList; |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.ListIterator; |
| import java.util.NoSuchElementException; |
| |
| import org.apache.commons.lang.ObjectUtils; |
| |
| /** |
| * Abstract base class for random-access result lists. Unlike the |
| * {@link AbstractList}, this class doesn't rely on the |
| * {@link Collection#size} method. |
| * |
| * @author Abe White |
| * @nojavadoc |
| */ |
| public abstract class AbstractNonSequentialResultList |
| extends AbstractResultList { |
| |
| protected static final Object PAST_END = new Object(); |
| |
| /** |
| * Implement this method and {@link #size}. Return {@link #PAST_END} |
| * if the index is out of bounds. |
| */ |
| protected abstract Object getInternal(int index); |
| |
| public boolean contains(Object o) { |
| assertOpen(); |
| Object obj; |
| for (int i = 0; true; i++) { |
| obj = getInternal(i); |
| if (obj == PAST_END) |
| break; |
| if (ObjectUtils.equals(o, obj)) |
| return true; |
| } |
| return false; |
| } |
| |
| public boolean containsAll(Collection c) { |
| assertOpen(); |
| for (Iterator itr = c.iterator(); itr.hasNext();) |
| if (!contains(itr.next())) |
| return false; |
| return true; |
| } |
| |
| public Object get(int index) { |
| assertOpen(); |
| Object obj = getInternal(index); |
| if (obj == PAST_END) |
| throw new NoSuchElementException(); |
| return obj; |
| } |
| |
| public int indexOf(Object o) { |
| assertOpen(); |
| Object obj; |
| for (int i = 0; true; i++) { |
| obj = getInternal(i); |
| if (obj == PAST_END) |
| break; |
| if (ObjectUtils.equals(o, obj)) |
| return i; |
| } |
| return -1; |
| } |
| |
| public int lastIndexOf(Object o) { |
| assertOpen(); |
| int index = -1; |
| Object obj; |
| for (int i = 0; true; i++) { |
| obj = getInternal(i); |
| if (obj == PAST_END) |
| break; |
| if (ObjectUtils.equals(o, obj)) |
| index = i; |
| } |
| return index; |
| } |
| |
| public boolean isEmpty() { |
| assertOpen(); |
| return getInternal(0) == PAST_END; |
| } |
| |
| public Iterator iterator() { |
| return listIterator(); |
| } |
| |
| public ListIterator listIterator() { |
| return listIterator(0); |
| } |
| |
| public ListIterator listIterator(int index) { |
| return new ResultListIterator(new Itr(index), this); |
| } |
| |
| public Object[] toArray() { |
| assertOpen(); |
| ArrayList list = new ArrayList(); |
| Object obj; |
| for (int i = 0; true; i++) { |
| obj = getInternal(i); |
| if (obj == PAST_END) |
| break; |
| list.add(obj); |
| } |
| return list.toArray(); |
| } |
| |
| public Object[] toArray(Object[] a) { |
| assertOpen(); |
| ArrayList list = new ArrayList(); |
| Object obj; |
| for (int i = 0; true; i++) { |
| obj = getInternal(i); |
| if (obj == PAST_END) |
| break; |
| list.add(obj); |
| } |
| return list.toArray(a); |
| } |
| |
| public List subList(int fromIndex, int toIndex) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| private class Itr extends AbstractListIterator { |
| |
| private int _idx = 0; |
| private Object _next = PAST_END; |
| |
| public Itr(int index) { |
| _idx = index; |
| } |
| |
| public int nextIndex() { |
| return _idx; |
| } |
| |
| public int previousIndex() { |
| return _idx - 1; |
| } |
| |
| public boolean hasNext() { |
| _next = getInternal(_idx); |
| return _next != PAST_END; |
| } |
| |
| public boolean hasPrevious() { |
| return _idx > 0; |
| } |
| |
| public Object previous() { |
| if (_idx == 0) |
| throw new NoSuchElementException(); |
| return getInternal(--_idx); |
| } |
| |
| public Object next() { |
| if (!hasNext()) |
| throw new NoSuchElementException(); |
| _idx++; |
| return _next; |
| } |
| } |
| } |