| /* |
| * 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. |
| */ |
| |
| /* $Id$ */ |
| |
| package org.apache.fop.layoutmgr; |
| |
| import java.util.List; |
| import java.util.ListIterator; |
| import java.util.NoSuchElementException; |
| |
| /** An iterator for layout managers. */ |
| public class LMiter implements ListIterator<LayoutManager> { |
| |
| /** list of layout managers */ |
| protected List<LayoutManager> listLMs; |
| /** current position in iteration */ |
| protected int curPos; |
| /** The LayoutManager to which this LMiter is attached **/ |
| private LayoutManager lp; |
| |
| /** |
| * Construct a layout manager iterator. |
| * @param lp the associated layout manager (parent) |
| */ |
| public LMiter(LayoutManager lp) { |
| this.lp = lp; |
| listLMs = lp.getChildLMs(); |
| } |
| |
| /** {@inheritDoc} */ |
| public boolean hasNext() { |
| return (curPos < listLMs.size()) || lp.createNextChildLMs(curPos); |
| } |
| |
| /** {@inheritDoc} */ |
| public boolean hasPrevious() { |
| return (curPos > 0); |
| } |
| |
| /** {@inheritDoc} */ |
| public LayoutManager previous() throws NoSuchElementException { |
| if (curPos > 0) { |
| return listLMs.get(--curPos); |
| } else { |
| throw new NoSuchElementException(); |
| } |
| } |
| |
| /** {@inheritDoc} */ |
| public LayoutManager next() throws NoSuchElementException { |
| if (curPos < listLMs.size()) { |
| return listLMs.get(curPos++); |
| } else { |
| throw new NoSuchElementException(); |
| } |
| } |
| |
| /** {@inheritDoc} */ |
| public void remove() throws NoSuchElementException { |
| if (curPos > 0) { |
| listLMs.remove(--curPos); |
| // Note: doesn't actually remove it from the base! |
| } else { |
| throw new NoSuchElementException(); |
| } |
| } |
| |
| |
| /** {@inheritDoc} */ |
| public void add(LayoutManager lm) throws UnsupportedOperationException { |
| throw new UnsupportedOperationException("LMiter doesn't support add"); |
| } |
| |
| /** {@inheritDoc} */ |
| public void set(LayoutManager lm) throws UnsupportedOperationException { |
| throw new UnsupportedOperationException("LMiter doesn't support set"); |
| } |
| |
| /** {@inheritDoc} */ |
| public int nextIndex() { |
| return curPos; |
| } |
| |
| /** {@inheritDoc} */ |
| public int previousIndex() { |
| return curPos - 1; |
| } |
| |
| } |