123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394 |
- /*
- * 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.ArrayList;
- import java.util.LinkedList;
- import java.util.List;
- import java.util.ListIterator;
- import java.util.Map;
-
- import org.apache.commons.logging.Log;
- import org.apache.commons.logging.LogFactory;
-
- import org.apache.fop.area.Area;
- import org.apache.fop.area.PageViewport;
- import org.apache.fop.fo.Constants;
- import org.apache.fop.fo.FONode;
- import org.apache.fop.fo.FObj;
- import org.apache.fop.fo.flow.RetrieveMarker;
-
- /**
- * The base class for most LayoutManagers.
- */
- public abstract class AbstractLayoutManager extends AbstractBaseLayoutManager
- implements Constants {
-
- /**
- * logging instance
- */
- private static Log log = LogFactory.getLog(AbstractLayoutManager.class);
-
- /** Parent LayoutManager for this LayoutManager */
- protected LayoutManager parentLM = null;
- /** List of child LayoutManagers */
- protected List childLMs = null;
- /** Iterator for child LayoutManagers */
- protected ListIterator fobjIter = null;
- /** Marker map for markers related to this LayoutManager */
- private Map markers = null;
-
- /** True if this LayoutManager has handled all of its content. */
- private boolean bFinished = false;
-
- /** child LM during getNextKnuthElement phase */
- protected LayoutManager curChildLM = null;
-
- /** child LM iterator during getNextKnuthElement phase */
- protected ListIterator childLMiter = null;
-
- private int lastGeneratedPosition = -1;
- private int smallestPosNumberChecked = Integer.MAX_VALUE;
-
- /**
- * Abstract layout manager.
- */
- public AbstractLayoutManager() {
- }
-
- /**
- * Abstract layout manager.
- *
- * @param fo the formatting object for this layout manager
- */
- public AbstractLayoutManager(FObj fo) {
- super(fo);
- if (fo == null) {
- throw new IllegalStateException("Null formatting object found.");
- }
- markers = fo.getMarkers();
- fobjIter = fo.getChildNodes();
- childLMiter = new LMiter(this);
- }
-
- /** {@inheritDoc} */
- public void setParent(LayoutManager lm) {
- this.parentLM = lm;
- }
-
- /** {@inheritDoc} */
- public LayoutManager getParent() {
- return this.parentLM;
- }
-
- /** {@inheritDoc} */
- public void initialize() {
- // Empty
- }
-
- /**
- * Return currently active child LayoutManager or null if
- * all children have finished layout.
- * Note: child must implement LayoutManager! If it doesn't, skip it
- * and print a warning.
- * @return the current child LayoutManager
- */
- protected LayoutManager getChildLM() {
- if (curChildLM != null && !curChildLM.isFinished()) {
- return curChildLM;
- }
- if (childLMiter.hasNext()) {
- curChildLM = (LayoutManager) childLMiter.next();
- curChildLM.initialize();
- return curChildLM;
- }
- return null;
- }
-
- /**
- * Return indication if getChildLM will return another LM.
- * @return true if another child LM is still available
- */
- protected boolean hasNextChildLM() {
- return childLMiter.hasNext();
- }
-
- /**
- * Tell whether this LayoutManager has handled all of its content.
- * @return True if there are no more break possibilities,
- * ie. the last one returned represents the end of the content.
- */
- public boolean isFinished() {
- return bFinished;
- }
-
- /**
- * Set the flag indicating the LayoutManager has handled all of its content.
- * @param fin the flag value to be set
- */
- public void setFinished(boolean fin) {
- bFinished = fin;
- }
-
- /**
- * {@inheritDoc}
- */
- public void addAreas(PositionIterator posIter, LayoutContext context) {
- }
-
- /**
- * {@inheritDoc}
- */
- public LinkedList getNextKnuthElements(LayoutContext context,
- int alignment) {
- log.warn("null implementation of getNextKnuthElements() called!");
- setFinished(true);
- return null;
- }
-
- /**
- * {@inheritDoc}
- */
- public LinkedList getChangedKnuthElements(List oldList,
- int alignment) {
- log.warn("null implementation of getChangeKnuthElement() called!");
- return null;
- }
-
- /**
- * Return an Area which can contain the passed childArea. The childArea
- * may not yet have any content, but it has essential traits set.
- * In general, if the LayoutManager already has an Area it simply returns
- * it. Otherwise, it makes a new Area of the appropriate class.
- * It gets a parent area for its area by calling its parent LM.
- * Finally, based on the dimensions of the parent area, it initializes
- * its own area. This includes setting the content IPD and the maximum
- * BPD.
- * @param childArea the child area for which the parent area is wanted
- * @return the parent area for the given child
- */
- public Area getParentArea(Area childArea) {
- return null;
- }
-
- /**
- * Add a child area to the current area. If this causes the maximum
- * dimension of the current area to be exceeded, the parent LM is called
- * to add it.
- * @param childArea the child area to be added
- */
- public void addChildArea(Area childArea) {
- }
-
- /**
- * Create the LM instances for the children of the
- * formatting object being handled by this LM.
- * @param size the requested number of child LMs
- * @return the list with the preloaded child LMs
- */
- protected List createChildLMs(int size) {
- if (fobjIter == null) {
- return null;
- }
- List newLMs = new ArrayList(size);
- while (fobjIter.hasNext() && newLMs.size() < size ) {
- Object theobj = fobjIter.next();
- if (theobj instanceof FONode) {
- FONode foNode = (FONode) theobj;
- if (foNode instanceof RetrieveMarker) {
- foNode = getPSLM().resolveRetrieveMarker(
- (RetrieveMarker) foNode);
- }
- if (foNode != null) {
- getPSLM().getLayoutManagerMaker().
- makeLayoutManagers(foNode, newLMs);
- }
- }
- }
- return newLMs;
- }
-
- /** {@inheritDoc} */
- public PageSequenceLayoutManager getPSLM() {
- return parentLM.getPSLM();
- }
-
- /**
- * @see PageSequenceLayoutManager#getCurrentPage()
- * @return the {@link Page} instance corresponding to the current page
- */
- public Page getCurrentPage() {
- return getPSLM().getCurrentPage();
- }
-
- /** @return the current page viewport */
- public PageViewport getCurrentPV() {
- return getPSLM().getCurrentPage().getPageViewport();
- }
-
- /**
- * {@inheritDoc}
- */
- public boolean createNextChildLMs(int pos) {
- List newLMs = createChildLMs(pos + 1 - childLMs.size());
- addChildLMs(newLMs);
- return pos < childLMs.size();
- }
-
- /**
- * {@inheritDoc}
- */
- public List getChildLMs() {
- if (childLMs == null) {
- childLMs = new java.util.ArrayList(10);
- }
- return childLMs;
- }
-
- /**
- * {@inheritDoc}
- */
- public void addChildLM(LayoutManager lm) {
- if (lm == null) {
- return;
- }
- lm.setParent(this);
- if (childLMs == null) {
- childLMs = new java.util.ArrayList(10);
- }
- childLMs.add(lm);
- log.trace(this.getClass().getName()
- + ": Adding child LM " + lm.getClass().getName());
- }
-
- /**
- * {@inheritDoc}
- */
- public void addChildLMs(List newLMs) {
- if (newLMs == null || newLMs.size() == 0) {
- return;
- }
- ListIterator iter = newLMs.listIterator();
- while (iter.hasNext()) {
- LayoutManager lm = (LayoutManager) iter.next();
- addChildLM(lm);
- }
- }
-
- /**
- * Adds a Position to the Position participating in the first|last determination by assigning
- * it a unique position index.
- * @param pos the Position
- * @return the same Position but with a position index
- */
- public Position notifyPos(Position pos) {
- if (pos.getIndex() >= 0) {
- throw new IllegalStateException("Position already got its index");
- }
- lastGeneratedPosition++;
- pos.setIndex(lastGeneratedPosition);
- return pos;
- }
-
- /**
- * Indicates whether the given Position is the first area-generating Position of this LM.
- * @param pos the Position (must be one with a position index)
- * @return True if it is the first Position
- */
- public boolean isFirst(Position pos) {
- //log.trace("isFirst() smallestPosNumberChecked=" + smallestPosNumberChecked + " " + pos);
- if (pos == null || pos.getIndex() < 0) {
- throw new IllegalArgumentException("Only non-null Positions with an index can be checked");
- }
- if (pos.getIndex() == this.smallestPosNumberChecked) {
- return true;
- } else if (pos.getIndex() < this.smallestPosNumberChecked) {
- this.smallestPosNumberChecked = pos.getIndex();
- return true;
- } else {
- return false;
- }
- }
-
- /**
- * Indicates whether the given Position is the last area-generating Position of this LM.
- * @param pos the Position (must be one with a position index)
- * @return True if it is the last Position
- */
- public boolean isLast(Position pos) {
- //log.trace("isLast() lastGenPos=" + lastGeneratedPosition + " " + pos);
- if (pos == null || pos.getIndex() < 0) {
- throw new IllegalArgumentException("Only non-null Positions with an index can be checked");
- }
- return (pos.getIndex() == this.lastGeneratedPosition
- && isFinished());
- }
-
- /**
- * Transfers foreign attributes from the formatting object to the area.
- * @param targetArea the area to set the attributes on
- */
- protected void transferForeignAttributes(Area targetArea) {
- Map atts = fobj.getForeignAttributes();
- targetArea.setForeignAttributes(atts);
- }
-
- /**
- * Registers the FO's markers on the current PageViewport
- *
- * @param isStarting boolean indicating whether the markers qualify as 'starting'
- * @param isFirst boolean indicating whether the markers qualify as 'first'
- * @param isLast boolean indicating whether the markers qualify as 'last'
- */
- protected void addMarkersToPage(boolean isStarting, boolean isFirst, boolean isLast) {
- if (this.markers != null) {
- getCurrentPV().addMarkers(
- this.markers,
- isStarting,
- isFirst,
- isLast);
- }
- }
-
- /**
- * Registers the FO's id on the current PageViewport
- */
- protected void addId() {
- if (fobj != null) {
- getPSLM().addIDToPage(fobj.getId());
- }
- }
-
- /**
- * Notifies the {@link PageSequenceLayoutManager} that layout
- * for this LM has ended.
- */
- protected void notifyEndOfLayout() {
- if (fobj != null) {
- getPSLM().notifyEndOfLayout(fobj.getId());
- }
- }
-
- /** {@inheritDoc} */
- public String toString() {
- return (super.toString() + (fobj != null ? "[fobj=" + fobj.toString() + "]" : ""));
- }
-
- }
|