Package org.apache.fop.layoutmgr

Class PageBreaker

  • public class PageBreaker
extends AbstractBreaker
    Handles the breaking of pages in an fo:flow

    • Field Detail

      • firstPart

        private boolean firstPart

      • pageBreakHandled

        private boolean pageBreakHandled

      • needColumnBalancing

        private boolean needColumnBalancing

      • separatorArea

        private Block separatorArea

      • spanAllActive

        private boolean spanAllActive

      • layoutRedone

        private boolean layoutRedone

      • previousIndex

        private int previousIndex

      • handlingStartOfFloat

        private boolean handlingStartOfFloat

      • handlingEndOfFloat

        private boolean handlingEndOfFloat

      • floatHeight

        private int floatHeight

      • floatYOffset

        private int floatYOffset

      • relayedFootnotesList

        private java.util.List relayedFootnotesList

      • relayedLengthList

        private java.util.List relayedLengthList

      • relayedTotalFootnotesLength

        private int relayedTotalFootnotesLength

      • relayedInsertedFootnotesLength

        private int relayedInsertedFootnotesLength

      • relayedFootnotesPending

        private boolean relayedFootnotesPending

      • relayedNewFootnotes

        private boolean relayedNewFootnotes

      • relayedFirstNewFootnoteIndex

        private int relayedFirstNewFootnoteIndex

      • relayedFootnoteListIndex

        private int relayedFootnoteListIndex

      • relayedFootnoteElementIndex

        private int relayedFootnoteElementIndex

      • relayedFootnoteSeparatorLength

        private MinOptMax relayedFootnoteSeparatorLength

      • previousFootnoteListIndex

        private int previousFootnoteListIndex

      • previousFootnoteElementIndex

        private int previousFootnoteElementIndex

      • prevousColumnCount

        private int prevousColumnCount

      • childFLM

        private FlowLayoutManager childFLM
        The FlowLayoutManager object, which processes the single fo:flow of the fo:page-sequence

    • Constructor Detail

      • PageBreaker

        public PageBreaker​(PageSequenceLayoutManager pslm)
        Construct page breaker.
        Parameters:
        pslm - the page sequence layout manager

    • Method Detail

      • updateLayoutContext

        protected void updateLayoutContext​(LayoutContext context)
        Used to update the LayoutContext in subclasses prior to starting a new element list.
        Overrides:
        updateLayoutContext in class AbstractBreaker
        Parameters:
        context - the LayoutContext to update

      • getPageProvider

        protected PageProvider getPageProvider()
        Returns the PageProvider if any. PageBreaker overrides this method because each page may have a different available BPD which needs to be accessible to the breaking algorithm.
        Overrides:
        getPageProvider in class AbstractBreaker
        Returns:
        the applicable PageProvider, or null if not applicable

      • doLayout

        boolean doLayout​(int flowBPD)
        Starts the page breaking process.
        Parameters:
        flowBPD - the constant available block-progression-dimension (used for every part)

      • handleSpanChange

        protected int handleSpanChange​(LayoutContext childLC,
                               int nextSequenceStartsOn)
        Handles span changes reported through the LayoutContext. Only used by the PSLM and called by getNextBlockList().
        Overrides:
        handleSpanChange in class AbstractBreaker
        Parameters:
        childLC - the LayoutContext
        nextSequenceStartsOn - previous value for break handling
        Returns:
        effective value for break handling

      • getNextBlockList

        protected int getNextBlockList​(LayoutContext childLC,
                               int nextSequenceStartsOn)
        Gets the next block list (sequence) and adds it to a list of block lists if it's not empty.
        Overrides:
        getNextBlockList in class AbstractBreaker
        Parameters:
        childLC - LayoutContext to use
        nextSequenceStartsOn - indicates on what page the next sequence should start
        Returns:
        the page on which the next content should appear after a hard break

      • getNextBlockList

        protected int getNextBlockList​(LayoutContext childLC,
                               int nextSequenceStartsOn,
                               Position positionAtIPDChange,
                               LayoutManager restartLM,
                               java.util.List firstElements)
        Gets the next block list (sequence) and adds it to a list of block lists if it's not empty.
        Overrides:
        getNextBlockList in class AbstractBreaker
        Parameters:
        childLC - LayoutContext to use
        nextSequenceStartsOn - indicates on what page the next sequence should start
        positionAtIPDChange - last element on the part before an IPD change
        restartLM - the layout manager from which to restart, if IPD change occurs between two LMs
        firstElements - elements from non-restartable LMs on the new page
        Returns:
        the page on which the next content should appear after a hard break

      • containsFootnotes

        private boolean containsFootnotes​(java.util.List contentList,
                                  LayoutContext context)

      • handleFootnoteSeparator

        private void handleFootnoteSeparator()

      • getNextKnuthElements

        protected java.util.List getNextKnuthElements​(LayoutContext context,
                                              int alignment)
        Get a sequence of KnuthElements representing the content of the node assigned to the LM
        Specified by:
        getNextKnuthElements in class AbstractBreaker
        Parameters:
        context - the LayoutContext used to store layout information
        alignment - the desired text alignment
        Returns:
        the list of KnuthElements

      • getNextKnuthElements

        protected java.util.List getNextKnuthElements​(LayoutContext context,
                                              int alignment,
                                              Position positionAtIPDChange,
                                              LayoutManager restartAtLM)
        Get a sequence of KnuthElements representing the content of the node assigned to the LM
        Overrides:
        getNextKnuthElements in class AbstractBreaker
        Parameters:
        context - the LayoutContext used to store layout information
        alignment - the desired text alignment
        positionAtIPDChange - last element on the part before an IPD change
        restartAtLM - the layout manager from which to restart, if IPD change occurs between two LMs
        Returns:
        the list of KnuthElements

      • hasMoreContent

        protected boolean hasMoreContent()
        Specified by:
        hasMoreContent in class AbstractBreaker
        Returns:
        whether or not this flow has more page break opportunities

      • doPhase3

        protected void doPhase3​(PageBreakingAlgorithm alg,
                        int partCount,
                        AbstractBreaker.BlockSequence originalList,
                        AbstractBreaker.BlockSequence effectiveList)
        Phase 3 of Knuth algorithm: Adds the areas This implementation checks whether to trigger column-balancing, or whether to take into account a 'last-page' condition.
        Specified by:
        doPhase3 in class AbstractBreaker
        Parameters:
        alg - PageBreakingAlgorithm instance which determined the breaks
        partCount - number of parts (pages) to be rendered
        originalList - original Knuth element list
        effectiveList - effective Knuth element list (after adjustments)

      • setLastPageIndex

        private void setLastPageIndex​(int currentPageNum)

      • handleEmptyContent

        protected void handleEmptyContent()
        This method is called when no content is available for a part. Used to force empty pages.
        Overrides:
        handleEmptyContent in class AbstractBreaker

      • addFootnoteAreas

        private void addFootnoteAreas​(java.util.List<KnuthElement> footnote)

      • addFootnoteAreas

        private void addFootnoteAreas​(java.util.List<KnuthElement> footnote,
                              int startIndex,
                              int endIndex)

      • observeElementList

        protected void observeElementList​(java.util.List elementList)
        Used for debugging purposes. Notifies all registered observers about the element list. Override to set different parameters.
        Overrides:
        observeElementList in class AbstractBreaker
        Parameters:
        elementList - the Knuth element list

      • handleBreakTrait

        private void handleBreakTrait​(int breakVal)
        Depending on the kind of break condition, move to next column or page. May need to make an empty page if next page would not have the desired "handedness".
        Parameters:
        breakVal - - value of break-before or break-after trait.

      • handleBreakTrait

        private void handleBreakTrait​(int breakVal,
                              boolean emptyContent)

      • handleBreakBeforeFollowingPage

        private void handleBreakBeforeFollowingPage​(int breakVal)

      • needBlankPageBeforeNew

        private boolean needBlankPageBeforeNew​(int breakVal)
        Check if a blank page is needed to accommodate desired even or odd page number.
        Parameters:
        breakVal - - value of break-before or break-after trait.

      • needNewPage

        private boolean needNewPage​(int breakVal)
        See if need to generate a new page
        Parameters:
        breakVal - - value of break-before or break-after trait.

      • shouldRedoLayout

        protected boolean shouldRedoLayout​(int partCount)

      • handlingStartOfFloat

        protected boolean handlingStartOfFloat()

      • handleStartOfFloat

        protected void handleStartOfFloat​(int fHeight,
                                  int fYOffset)

      • getFloatHeight

        protected int getFloatHeight()

      • getFloatYOffset

        protected int getFloatYOffset()

      • handlingEndOfFloat

        protected boolean handlingEndOfFloat()

      • handleEndOfFloat

        protected void handleEndOfFloat​(int fHeight)

      • handlingFloat

        protected boolean handlingFloat()

      • getOffsetDueToFloat

        public int getOffsetDueToFloat()

      • holdFootnotes

        public void holdFootnotes​(java.util.List fl,
                          java.util.List ll,
                          int tfl,
                          int ifl,
                          boolean fp,
                          boolean nf,
                          int fnfi,
                          int fli,
                          int fei,
                          MinOptMax fsl,
                          int pfli,
                          int pfei)