| /* |
| * 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.Collections; |
| import java.util.Iterator; |
| import java.util.LinkedList; |
| |
| import org.apache.fop.events.EventBroadcaster; |
| |
| /** |
| * Class to find the restart layoutmanager for changing IPD |
| */ |
| class RestartAtLM { |
| protected boolean invalidPosition; |
| |
| protected LayoutManager getRestartAtLM(AbstractBreaker breaker, PageBreakingAlgorithm alg, |
| boolean ipdChangesOnNextPage, boolean onLastPageAndIPDChanges, |
| boolean visitedBefore, AbstractBreaker.BlockSequence blockList, int start) { |
| BreakingAlgorithm.KnuthNode optimalBreak = ipdChangesOnNextPage ? alg.getBestNodeBeforeIPDChange() : alg |
| .getBestNodeForLastPage(); |
| if (onLastPageAndIPDChanges && visitedBefore && breaker.originalRestartAtLM == null) { |
| optimalBreak = null; |
| } |
| int positionIndex = findPositionIndex(breaker, optimalBreak, alg, start); |
| if (ipdChangesOnNextPage || (breaker.positionAtBreak != null && breaker.positionAtBreak.getIndex() > -1)) { |
| breaker.firstElementsForRestart = Collections.EMPTY_LIST; |
| if (ipdChangesOnNextPage) { |
| if (breaker.containsNonRestartableLM(breaker.positionAtBreak)) { |
| if (alg.getIPDdifference() > 0) { |
| EventBroadcaster eventBroadcaster = breaker.getCurrentChildLM().getFObj() |
| .getUserAgent().getEventBroadcaster(); |
| BlockLevelEventProducer eventProducer = BlockLevelEventProducer.Provider |
| .get(eventBroadcaster); |
| eventProducer.nonRestartableContentFlowingToNarrowerPage(this); |
| } |
| breaker.firstElementsForRestart = new LinkedList(); |
| boolean boxFound = false; |
| Iterator iter = blockList.listIterator(positionIndex + 1); |
| Position position = null; |
| while (iter.hasNext() |
| && (position == null || breaker.containsNonRestartableLM(position))) { |
| positionIndex++; |
| KnuthElement element = (KnuthElement) iter.next(); |
| position = element.getPosition(); |
| if (element.isBox()) { |
| boxFound = true; |
| breaker.firstElementsForRestart.add(element); |
| } else if (boxFound) { |
| breaker.firstElementsForRestart.add(element); |
| } |
| } |
| if (position instanceof SpaceResolver.SpaceHandlingBreakPosition) { |
| /* Retrieve the original position wrapped into this space position */ |
| breaker.positionAtBreak = position.getPosition(); |
| } else { |
| breaker.positionAtBreak = null; |
| } |
| } |
| } |
| } |
| LayoutManager restartAtLM = null; |
| if (ipdChangesOnNextPage || !(breaker.positionAtBreak != null && breaker.positionAtBreak.getIndex() > -1)) { |
| if (breaker.positionAtBreak != null && breaker.positionAtBreak.getIndex() == -1) { |
| Position position; |
| Iterator iter = blockList.listIterator(positionIndex + 1); |
| do { |
| KnuthElement nextElement = (KnuthElement) iter.next(); |
| position = nextElement.getPosition(); |
| } while (position == null |
| || position instanceof SpaceResolver.SpaceHandlingPosition |
| || position instanceof SpaceResolver.SpaceHandlingBreakPosition |
| && position.getPosition().getIndex() == -1); |
| LayoutManager surroundingLM = breaker.positionAtBreak.getLM(); |
| while (position.getLM() != surroundingLM) { |
| position = position.getPosition(); |
| } |
| if (position.getPosition() == null) { |
| position.getLM().getFObj().setForceKeepTogether(true); |
| invalidPosition = true; |
| return null; |
| } |
| restartAtLM = position.getPosition().getLM(); |
| } |
| if (onLastPageAndIPDChanges && restartAtLM != null) { |
| if (breaker.originalRestartAtLM == null) { |
| breaker.originalRestartAtLM = restartAtLM; |
| } else { |
| restartAtLM = breaker.originalRestartAtLM; |
| } |
| breaker.firstElementsForRestart = Collections.EMPTY_LIST; |
| } |
| } |
| if (onLastPageAndIPDChanges && !visitedBefore && breaker.positionAtBreak.getPosition() != null) { |
| restartAtLM = breaker.positionAtBreak.getPosition().getLM(); |
| } |
| return restartAtLM; |
| } |
| |
| private int findPositionIndex(AbstractBreaker breaker, BreakingAlgorithm.KnuthNode optimalBreak, |
| PageBreakingAlgorithm alg, int start) { |
| int positionIndex = (optimalBreak != null) ? optimalBreak.position : start; |
| for (int i = positionIndex; i < alg.par.size(); i++) { |
| KnuthElement elementAtBreak = alg.getElement(i); |
| if (elementAtBreak.getPosition() == null) { |
| elementAtBreak = alg.getElement(0); |
| } |
| breaker.positionAtBreak = elementAtBreak.getPosition(); |
| /* Retrieve the original position wrapped into this space position */ |
| breaker.positionAtBreak = breaker.positionAtBreak.getPosition(); |
| if (breaker.positionAtBreak != null) { |
| return i; |
| } |
| } |
| return positionIndex; |
| } |
| } |