org.apache.fop.layoutmgr.RestartAtLM Maven / Gradle / Ivy
/*
* 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;
}
}