package com.planet_ink.coffee_mud.core.collections; import java.util.ArrayList; import java.util.Collection; import java.util.Enumeration; import java.util.Iterator; import java.util.LinkedList; import java.util.List; import java.util.ListIterator; import java.util.NoSuchElementException; import java.util.Vector; /* Copyright 2016-2016 Bo Zimmerman Licensed 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. */ public class MultiListListIterator<K> implements ListIterator<K> { private final List<ListIterator<K>> iters=new ArrayList<ListIterator<K>>(); private volatile ListIterator<K> iter=null; private volatile int listIndex = 0; private volatile int itemIndex = 0; public MultiListListIterator(ListIterator<K>[] esets) { if((esets==null)||(esets.length==0)) return; for(final ListIterator<K> I : esets) iters.add(I); } public MultiListListIterator(Collection<ListIterator<K>> esets) { if((esets==null)||(esets.size()==0)) return; iters.addAll(esets); for(final ListIterator<K> I : esets) iters.add(I); } public MultiListListIterator(List<K>[] esets) { if((esets==null)||(esets.length==0)) return; for(final List<K> I : esets) iters.add(I.listIterator()); } public MultiListListIterator(List<? extends List<K>> esets) { if(esets==null) return; for(final List<K> I : esets) iters.add(I.listIterator()); } public MultiListListIterator() { } public void add(ListIterator<K> eset) { iters.add(eset); } @Override public boolean hasNext() { boolean hasNext = (iter != null) && iter.hasNext(); while(!hasNext) { if((iters.size()==0) ||(listIndex<0) ||(listIndex>=iters.size())) { iter=null; return false; } iter=iters.get(listIndex++); hasNext = (iter != null) && iter.hasNext(); } return hasNext; } @Override public K next() { if(!hasNext()) throw new NoSuchElementException(); itemIndex++; return iter.next(); } @Override public void remove() { if(iter != null) iter.remove(); } @Override public boolean hasPrevious() { boolean hasPrevious = (iter != null) && iter.hasPrevious(); while(!hasPrevious) { if((iters.size()==0) ||(listIndex<0) ||(listIndex>=iters.size())) { iter=null; return false; } iter=iters.get(listIndex--); hasPrevious = (iter != null) && iter.hasPrevious(); } return hasPrevious; } @Override public K previous() { if(!hasPrevious()) throw new NoSuchElementException(); itemIndex--; return iter.previous(); } @Override public int nextIndex() { return itemIndex; } @Override public int previousIndex() { return itemIndex-1; } @Override public void set(K e) { if(hasNext()) iter.set(e); else if(hasPrevious()) iter.set(e); } @Override public void add(K e) { if(hasNext()) iter.add(e); else if(hasPrevious()) iter.add(e); } }