/*-- $Id: Flow.java,v 1.19 2001/02/11 00:59:26 arved Exp $ --
============================================================================
The Apache Software License, Version 1.1
============================================================================
Copyright (C) 1999 The Apache Software Foundation. All rights reserved.
Redistribution and use in source and binary forms, with or without modifica-
tion, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
3. The end-user documentation included with the redistribution, if any, must
include the following acknowledgment: "This product includes software
developed by the Apache Software Foundation (http://www.apache.org/)."
Alternately, this acknowledgment may appear in the software itself, if
and wherever such third-party acknowledgments normally appear.
4. The names "FOP" and "Apache Software Foundation" must not be used to
endorse or promote products derived from this software without prior
written permission. For written permission, please contact
apache@apache.org.
5. Products derived from this software may not be called "Apache", nor may
"Apache" appear in their name, without prior written permission of the
Apache Software Foundation.
THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
APACHE SOFTWARE FOUNDATION OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLU-
DING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
This software consists of voluntary contributions made by many individuals
on behalf of the Apache Software Foundation and was originally created by
James Tauber <jtauber@jtauber.com>. For more information on the Apache
Software Foundation, please see <http://www.apache.org/>.
*/
package org.apache.fop.fo.flow;
// FOP
import org.apache.fop.fo.*;
import org.apache.fop.fo.properties.*;
import org.apache.fop.fo.pagination.*;
import org.apache.fop.layout.Area;
import org.apache.fop.layout.BodyAreaContainer;
import org.apache.fop.apps.FOPException;
import org.apache.fop.messaging.MessageHandler;
// Java
import java.util.Hashtable;
import java.util.Enumeration;
import java.util.Vector;
public class Flow extends FObj {
public static class Maker extends FObj.Maker {
public FObj make(FObj parent, PropertyList propertyList)
throws FOPException {
return new Flow(parent, propertyList);
}
}
public static FObj.Maker maker() {
return new Flow.Maker();
}
/** PageSequence container */
private PageSequence pageSequence;
/** Area in which we lay out our kids */
private Area area;
/** Vector to store snapshot */
private Vector markerSnapshot;
/** flow-name attribute */
private String _flowName;
private Status _status = new Status(Status.AREA_FULL_NONE);
protected Flow(FObj parent, PropertyList propertyList)
throws FOPException {
super(parent, propertyList);
this.name = getElementName();
if (parent.getName().equals("fo:page-sequence")) {
this.pageSequence = (PageSequence) parent;
} else {
throw new FOPException("flow must be child of "
+ "page-sequence, not "
+ parent.getName());
}
setFlowName(getProperty("flow-name").getString());
// according to communication from Paul Grosso (XSL-List,
// 001228, Number 406), confusion in spec section 6.4.5 about
// multiplicity of fo:flow in XSL 1.0 is cleared up - one (1)
// fo:flow per fo:page-sequence only.
if (pageSequence.isFlowSet()) {
if (this.name.equals("fo:flow")) {
throw new FOPException("Only a single fo:flow permitted"
+ " per fo:page-sequence");
}
else {
throw new FOPException(this.name+" not allowed after fo:flow");
}
}
pageSequence.addFlow(this);
}
protected void setFlowName(String name)
throws FOPException
{
if (name == null || name.equals("")) {
MessageHandler.errorln("WARNING: A 'flow-name' is required for "+getElementName()+". This constraint will be enforced in future versions of FOP");
_flowName = "xsl-region-body";
}
else {
_flowName = name;
}
}
public String getFlowName()
{
return _flowName;
}
public Status layout(Area area) throws FOPException {
return layout(area, null);
}
public Status layout(Area area, Region region) throws FOPException {
if (this.marker == START) {
this.marker = 0;
}
// flow is *always* laid out into a BodyAreaContainer
BodyAreaContainer bac = (BodyAreaContainer)area;
boolean prevChildMustKeepWithNext = false;
Vector pageMarker = this.getMarkerSnapshot(new Vector());
int numChildren = this.children.size();
if (numChildren == 0)
{
throw new FOPException("fo:flow must contain block-level children");
}
for (int i = this.marker; i < numChildren; i++) {
FObj fo = (FObj) children.elementAt(i);
if (bac.isBalancingRequired(fo))
{
// reset the the just-done span area in preparation
// for a backtrack for balancing
bac.resetSpanArea();
this.rollback(markerSnapshot);
// one less because of the "continue"
i = this.marker - 1;
continue;
}
// current column area
Area currentArea = bac.getNextArea(fo);
// temporary hack for IDReferences
currentArea.setIDReferences(bac.getIDReferences());
if (bac.isNewSpanArea())
{
this.marker = i;
markerSnapshot = this.getMarkerSnapshot(new Vector());
}
_status = fo.layout(currentArea);
/* if((_status.isPageBreak() || i == numChildren - 1) && bac.needsFootnoteAdjusting()) {
bac.adjustFootnoteArea();
this.rollback(pageMarker);
i = this.marker - 1;
Area mainReferenceArea = bac.getMainReferenceArea();
// remove areas
continue;
}*/
if (_status.isIncomplete()) {
if ((prevChildMustKeepWithNext) && (_status.laidOutNone())) {
this.marker = i - 1;
FObj prevChild = (FObj) children.elementAt(this.marker);
prevChild.removeAreas();
prevChild.resetMarker();
prevChild.removeID(area.getIDReferences());
_status = new Status(Status.AREA_FULL_SOME);
return _status;
// should probably return AREA_FULL_NONE if first
// or perhaps an entirely new status code
}
if (bac.isLastColumn())
if (_status.getCode() == Status.FORCE_COLUMN_BREAK) {
this.marker = i;
_status = new Status(Status.FORCE_PAGE_BREAK); // same thing
return _status;
}
else {
this.marker = i;
return _status;
}
else
{
// not the last column, but could be page breaks
if (_status.isPageBreak())
{
this.marker = i;
return _status;
}
// I don't much like exposing this. (AHS 001217)
((org.apache.fop.layout.ColumnArea)currentArea).incrementSpanIndex();
i--;
}
}
if (_status.getCode() == Status.KEEP_WITH_NEXT) {
prevChildMustKeepWithNext = true;
}
else {
prevChildMustKeepWithNext = false;
}
}
return _status;
}
/**
* Return the content width of this flow (really of the region
* in which it is flowing).
*/
public int getContentWidth() {
if (area != null)
return area.getContentWidth(); //getAllocationWidth()??
else return 0; // not laid out yet
}
protected String getElementName()
{
return "fo:flow";
}
public Status getStatus()
{
return _status;
}
public boolean generatesReferenceAreas() {
return true;
}
}