org.jfree.layouting.renderer.process

Class ParagraphLineBreakStep


public class ParagraphLineBreakStep
extends IterateStructuralProcessStep

This static computation step performs manual linebreaks on all paragraphs. This transforms the pool-collection into the lines-collection.

For now, we follow a very simple path: A paragraph cannot be validated, if it is not yet closed. The linebreaking, be it the static one here or the dynamic one later, must be redone when the paragraph changes.

Splitting for linebreaks happens only between inline-boxes. BlockBoxes that are contained in inline-boxes (like 'inline-block' elements or 'inline-tables') are considered unbreakable according to the CSS specs. Linebreaking can be suspended in these cases.

As paragraphs itself are block elements, the linebreaks can be done iterative, using a simple stack to store the context of possibly nested paragraphs. The paragraph's pool contains the elements that should be processed, and the line-container will receive the pool's content (contained in an artificial inline element, as the linecontainer is a block-level element).

Change-tracking should take place on the paragraph's pool element instead of the paragraph itself. This way, only structural changes are taken into account.

Author:
Thomas Morgner

Constructor Summary

ParagraphLineBreakStep()

Method Summary

void
compute(LogicalPageBox root)
protected void
finishBlockBox(BlockRenderBox box)
protected void
finishInlineBox(InlineRenderBox box)
protected void
finishOtherBox(RenderBox box)
protected boolean
startBlockBox(BlockRenderBox box)
protected boolean
startInlineBox(InlineRenderBox box)
protected boolean
startOtherBox(RenderBox box)
protected void
startOtherNode(RenderNode node)

Methods inherited from class org.jfree.layouting.renderer.process.IterateStructuralProcessStep

finishBlockBox, finishInlineBox, finishNormalFlow, finishOtherBox, finishOtherNode, processBoxChilds, processParagraphChilds, startBlockBox, startInlineBox, startNormalFlow, startOtherBox, startOtherNode, startProcessing

Constructor Details

ParagraphLineBreakStep

public ParagraphLineBreakStep()

Method Details

compute

public void compute(LogicalPageBox root)

finishBlockBox

protected void finishBlockBox(BlockRenderBox box)
Overrides:
finishBlockBox in interface IterateStructuralProcessStep

finishInlineBox

protected void finishInlineBox(InlineRenderBox box)
Overrides:
finishInlineBox in interface IterateStructuralProcessStep

finishOtherBox

protected void finishOtherBox(RenderBox box)
Overrides:
finishOtherBox in interface IterateStructuralProcessStep

startBlockBox

protected boolean startBlockBox(BlockRenderBox box)
Overrides:
startBlockBox in interface IterateStructuralProcessStep

startInlineBox

protected boolean startInlineBox(InlineRenderBox box)
Overrides:
startInlineBox in interface IterateStructuralProcessStep

startOtherBox

protected boolean startOtherBox(RenderBox box)
Overrides:
startOtherBox in interface IterateStructuralProcessStep

startOtherNode

protected void startOtherNode(RenderNode node)
Overrides:
startOtherNode in interface IterateStructuralProcessStep