/**
* ===========================================
* LibLayout : a free Java layouting library
* ===========================================
*
* Project Info: http://reporting.pentaho.org/liblayout/
*
* (C) Copyright 2006-2007, by Pentaho Corporation and Contributors.
*
* This library is free software; you can redistribute it and/or modify it under the terms
* of the GNU Lesser General Public License as published by the Free Software Foundation;
* either version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
* without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307, USA.
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc.
* in the United States and other countries.]
*
* ------------
* $Id: CleanPaginatedBoxesStep.java 3524 2007-10-16 11:26:31Z tmorgner $
* ------------
* (C) Copyright 2006-2007, by Pentaho Corporation.
*/
package org.jfree.layouting.renderer.process;
import org.jfree.layouting.renderer.model.FinishedRenderNode;
import org.jfree.layouting.renderer.model.ParagraphRenderBox;
import org.jfree.layouting.renderer.model.RenderBox;
import org.jfree.layouting.renderer.model.RenderNode;
import org.jfree.layouting.renderer.model.page.LogicalPageBox;
import org.jfree.layouting.renderer.model.table.TableRowRenderBox;
import org.jfree.layouting.renderer.model.table.TableSectionRenderBox;
/**
* Creation-Date: 27.10.2006, 18:19:24
*
* @author Thomas Morgner
*/
public class CleanPaginatedBoxesStep extends IterateVisualProcessStep
{
private long pageOffset;
public CleanPaginatedBoxesStep()
{
}
public void compute(final LogicalPageBox pageBox)
{
pageOffset = pageBox.getPageOffset();
if (startBlockLevelBox(pageBox))
{
// not processing the header and footer area: they are 'out-of-context' bands
processBoxChilds(pageBox);
}
finishBlockLevelBox(pageBox);
}
protected void processParagraphChilds(final ParagraphRenderBox box)
{
// we do not process the paragraph lines. This should have been done
// in the startblock thing and they get re-added anyway as long as the
// paragraph is active.
}
protected boolean startBlockLevelBox(final RenderBox box)
{
if (box instanceof ParagraphRenderBox)
{
return false;
}
if (box instanceof TableSectionRenderBox)
{
// Table sections dont get removed at all.
return true;
}
if (box instanceof TableRowRenderBox)
{
// TableRows dont get removed now. We remove them when the close-event
// gets fired, and only if all cells have been replaced by removed-
// placeholders
return startTableRow((TableRowRenderBox) box);
}
final RenderNode node = box.getVisibleFirst();
if (node == null)
{
// The cell is empty ..
return false;
}
if (node.isOpen())
{
return true;
}
final long nodeY = node.getY();
if ((nodeY + node.getHeight()) > pageOffset)
{
// we cant handle that. At least parts of the node will be visible ..
if (nodeY > pageOffset)
{
// all childs will be visible too, so why visiting them ...
return false;
}
return true;
}
// Next, search the last node that is fully invisible. We collapse all
// invisible node into one big box for efficiency reasons. They wont be
// visible anyway and thus the result will be the same as if they were
// still alive ..
RenderNode last = node;
while (true)
{
final RenderNode next = last.getVisibleNext();
if (next == null)
{
break;
}
if (next.isOpen())
{
// as long as a box is open, it can grow and therefore it cannot be
// removed ..
break;
}
if ((next.getY() + next.getHeight()) > pageOffset)
{
// we cant handle that. This node will be visible. So the current last
// node is the one we can shrink ..
break;
}
last = next;
}
// So lets get started. We remove all nodes between (and inclusive)
// node and last.
final long width = box.getContentAreaX2() - box.getContentAreaX1();
final long height = last.getY() + last.getHeight() - nodeY;
// make sure that the finished-box inherits the margins ..
final long marginsTop = node.getEffectiveMarginTop();
final long marginsBottom = last.getEffectiveMarginBottom();
final FinishedRenderNode replacement =
new FinishedRenderNode(width, height, marginsTop, marginsBottom);
RenderNode removeNode = node;
while (removeNode != last)
{
final RenderNode next = removeNode.getNext();
if (removeNode.isOpen())
{
throw new IllegalStateException();
}
box.remove(removeNode);
removeNode = next;
}
if (last.isOpen())
{
throw new IllegalStateException();
}
box.replaceChild(last, replacement);
if (replacement.getParent() != box)
{
throw new IllegalStateException();
}
return (box.getLastChild() != replacement);
}
private boolean startTableRow(final TableRowRenderBox box)
{
// if the row's cells are all invisible, remove the row itself.
// todo: Shall we do this? For now, it might be sufficient to stick with
// the cleaned cells ..
return true;
}
}