static void rebuild()

in poi-scratchpad/src/main/java/org/apache/poi/hwpf/model/PAPBinTable.java [101:264]
135 lines of code
26 McCabe index (conditional complexity)

    static void rebuild( final StringBuilder docText,
            ComplexFileTable complexFileTable, List<PAPX> paragraphs )
    {
        long start = currentTimeMillis();

        if ( complexFileTable != null )
        {
            SprmBuffer[] sprmBuffers = complexFileTable.getGrpprls();

            // adding PAPX from fast-saved SPRMs
            for ( TextPiece textPiece : complexFileTable.getTextPieceTable()
                    .getTextPieces() )
            {
                PropertyModifier prm = textPiece.getPieceDescriptor().getPrm();
                if ( !prm.isComplex() )
                    continue;
                int igrpprl = prm.getIgrpprl();

                if ( igrpprl < 0 || igrpprl >= sprmBuffers.length )
                {
                    LOG.atWarn().log("{}'s PRM references to unknown grpprl", textPiece);
                    continue;
                }

                boolean hasPap = false;
                SprmBuffer sprmBuffer = sprmBuffers[igrpprl];
                for ( SprmIterator iterator = sprmBuffer.iterator(); iterator
                        .hasNext(); )
                {
                    SprmOperation sprmOperation = iterator.next();
                    if ( sprmOperation.getType() == SprmOperation.TYPE_PAP )
                    {
                        hasPap = true;
                        break;
                    }
                }

                if ( hasPap )
                {
                    SprmBuffer newSprmBuffer = new SprmBuffer( 2 );
                    newSprmBuffer.append( sprmBuffer.toByteArray() );

                    PAPX papx = new PAPX( textPiece.getStart(),
                            textPiece.getEnd(), newSprmBuffer );
                    paragraphs.add( papx );
                }
            }

            LOG.atDebug().log("Merged (?) with PAPX from complex file table in {} ms ({} elements in total)", box(currentTimeMillis() - start),box(paragraphs.size()));
            start = currentTimeMillis();
        }

        List<PAPX> oldPapxSortedByEndPos = new ArrayList<>(paragraphs);
        oldPapxSortedByEndPos.sort(PropertyNode.EndComparator);

        LOG.atDebug().log("PAPX sorted by end position in {} ms", box(currentTimeMillis() - start));
        start = currentTimeMillis();

        final Map<PAPX, Integer> papxToFileOrder = new IdentityHashMap<>();
        {
            int counter = 0;
            for ( PAPX papx : paragraphs )
            {
                papxToFileOrder.put( papx, Integer.valueOf( counter++ ) );
            }
        }
        final Comparator<PAPX> papxFileOrderComparator = (o1, o2) -> {
            Integer i1 = papxToFileOrder.get( o1 );
            Integer i2 = papxToFileOrder.get( o2 );
            return i1.compareTo( i2 );
        };

        LOG.atDebug().log("PAPX's order map created in {} ms", box(currentTimeMillis() - start));
        start = currentTimeMillis();

        List<PAPX> newPapxs = new LinkedList<>();
        int lastParStart = 0;
        int lastPapxIndex = 0;
        for ( int charIndex = 0; charIndex < docText.length(); charIndex++ )
        {
            final char c = docText.charAt( charIndex );
            if ( c != 13 && c != 7 && c != 12 )
                continue;

            final int startInclusive = lastParStart;
            final int endExclusive = charIndex + 1;

            boolean broken = false;
            List<PAPX> papxs = new LinkedList<>();
            for ( int papxIndex = lastPapxIndex; papxIndex < oldPapxSortedByEndPos
                    .size(); papxIndex++ )
            {
                broken = false;
                PAPX papx = oldPapxSortedByEndPos.get( papxIndex );

                assert startInclusive == 0
                        || papxIndex + 1 == oldPapxSortedByEndPos.size()
                        || papx.getEnd() > startInclusive;

                if ( papx.getEnd() - 1 > charIndex )
                {
                    lastPapxIndex = papxIndex;
                    broken = true;
                    break;
                }

                papxs.add( papx );
            }
            if ( !broken )
            {
                lastPapxIndex = oldPapxSortedByEndPos.size() - 1;
            }

            if ( papxs.isEmpty() )
            {
                LOG.atWarn().log("Paragraph [{}; {}) has no PAPX. Creating new one.", box(startInclusive),box(endExclusive));
                // create it manually
                PAPX papx = new PAPX( startInclusive, endExclusive,
                        new SprmBuffer( 2 ) );
                newPapxs.add( papx );

                lastParStart = endExclusive;
                continue;
            }

            if ( papxs.size() == 1 )
            {
                // can we reuse existing?
                PAPX existing = papxs.get( 0 );
                if ( existing.getStart() == startInclusive
                        && existing.getEnd() == endExclusive )
                {
                    newPapxs.add( existing );
                    lastParStart = endExclusive;
                    continue;
                }
            }

            // restore file order of PAPX
            papxs.sort(papxFileOrderComparator);

            SprmBuffer sprmBuffer = null;
            for ( PAPX papx : papxs )
            {
                if ( papx.getGrpprl() == null || papx.getGrpprl().length <= 2 )
                    continue;

                if ( sprmBuffer == null ) {
                    sprmBuffer = papx.getSprmBuf().copy();
                } else {
                    sprmBuffer.append( papx.getGrpprl(), 2 );
                }
            }
            PAPX newPapx = new PAPX( startInclusive, endExclusive, sprmBuffer );
            newPapxs.add( newPapx );

            lastParStart = endExclusive;
            continue;
        }
        paragraphs.clear();
        paragraphs.addAll( newPapxs );

        LOG.atDebug().log("PAPX rebuilded from document text in {} ms ({} elements)", box(currentTimeMillis() - start),box(paragraphs.size()));
    }