| /* ==================================================================== |
| 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.poi.xdgf.usermodel.section; |
| |
| import java.util.Collections; |
| import java.util.Iterator; |
| import java.util.Map.Entry; |
| import java.util.NoSuchElementException; |
| import java.util.Set; |
| import java.util.SortedMap; |
| |
| /** |
| * An iterator used to iterate over the base and master items |
| * |
| * @param <T> |
| */ |
| public class CombinedIterable<T> implements Iterable<T> { |
| |
| final SortedMap<Long, T> _baseItems; |
| final SortedMap<Long, T> _masterItems; |
| |
| public CombinedIterable(SortedMap<Long, T> baseItems, |
| SortedMap<Long, T> masterItems) { |
| _baseItems = baseItems; |
| _masterItems = masterItems; |
| } |
| |
| @Override |
| public Iterator<T> iterator() { |
| |
| final Iterator<Entry<Long, T>> vmasterI; |
| |
| if (_masterItems != null) { |
| vmasterI = _masterItems.entrySet().iterator(); |
| } else { |
| final Set<Entry<Long, T>> empty = Collections.emptySet(); |
| vmasterI = empty.iterator(); |
| } |
| |
| return new Iterator<T>() { |
| |
| Long lastI = Long.MIN_VALUE; |
| |
| Entry<Long, T> currentBase; |
| Entry<Long, T> currentMaster; |
| |
| // grab the iterator for both |
| Iterator<Entry<Long, T>> baseI = _baseItems.entrySet().iterator(); |
| Iterator<Entry<Long, T>> masterI = vmasterI; |
| |
| @Override |
| public boolean hasNext() { |
| return currentBase != null || currentMaster != null |
| || baseI.hasNext() || masterI.hasNext(); |
| } |
| |
| @Override |
| public T next() { |
| |
| // TODO: This seems far more complex than it needs to be |
| |
| long baseIdx = Long.MAX_VALUE; |
| long masterIdx = Long.MAX_VALUE; |
| |
| if (currentBase == null) { |
| while (baseI.hasNext()) { |
| currentBase = baseI.next(); |
| if (currentBase.getKey() > lastI) { |
| baseIdx = currentBase.getKey(); |
| break; |
| } |
| } |
| } else { |
| baseIdx = currentBase.getKey(); |
| } |
| |
| if (currentMaster == null) { |
| while (masterI.hasNext()) { |
| currentMaster = masterI.next(); |
| if (currentMaster.getKey() > lastI) { |
| masterIdx = currentMaster.getKey(); |
| break; |
| } |
| } |
| } else { |
| masterIdx = currentMaster.getKey(); |
| } |
| |
| T val; |
| |
| if (currentBase != null) { |
| |
| if (baseIdx <= masterIdx) { |
| lastI = baseIdx; |
| val = currentBase.getValue(); |
| |
| // discard master if same as base |
| if (masterIdx == baseIdx) { |
| currentMaster = null; |
| } |
| |
| currentBase = null; |
| |
| } else { |
| lastI = masterIdx; |
| val = (currentMaster != null) ? currentMaster.getValue() : null; |
| currentMaster = null; |
| } |
| |
| } else if (currentMaster != null) { |
| lastI = currentMaster.getKey(); |
| val = currentMaster.getValue(); |
| |
| currentMaster = null; |
| } else { |
| throw new NoSuchElementException(); |
| } |
| |
| return val; |
| } |
| |
| @Override |
| public void remove() { |
| throw new UnsupportedOperationException(); |
| } |
| }; |
| } |
| |
| } |