pdfmergerutility.java

非常有用的操作pdf文件的java源码

        }
        else
        {
            destThreads.addAll( srcThreads );
        }

        COSName names = COSName.getPDFName( "Names" );
        PDDocumentNameDictionary destNames = destCatalog.getNames();
        PDDocumentNameDictionary srcNames = srcCatalog.getNames();
        if( srcNames != null )
        {
            if( destNames == null )
            {
                destCatalog.getCOSDictionary().setItem( names, cloneForNewDocument( destination, srcNames ) );
            }
            else
            {
                //warning, potential for collision here!!
                destNames.getCOSDictionary().mergeInto( (COSDictionary)cloneForNewDocument( destination, srcNames ) );
            }
        }
        
        PDDocumentOutline destOutline = destCatalog.getDocumentOutline();
        PDDocumentOutline srcOutline = srcCatalog.getDocumentOutline();
        if( srcOutline != null )
        {
            if( destOutline == null )
            {
                PDDocumentOutline cloned = 
                    new PDDocumentOutline( (COSDictionary)cloneForNewDocument( destination, srcOutline ) );
                destCatalog.setDocumentOutline( cloned );
            }
            else
            {
                PDOutlineItem first = srcOutline.getFirstChild();
                PDOutlineItem clonedFirst = new PDOutlineItem( (COSDictionary)cloneForNewDocument( 
                        destination, first ));
                destOutline.appendChild( clonedFirst );
            }
        }
        
        String destPageMode = destCatalog.getPageMode();
        String srcPageMode = srcCatalog.getPageMode();
        if( destPageMode == null )
        {
            destCatalog.setPageMode( srcPageMode );
        }

        COSName pageLabels = COSName.getPDFName( "PageLabels" );
        COSDictionary destLabels = (COSDictionary)destCatalog.getCOSDictionary().getDictionaryObject( pageLabels );
        COSDictionary srcLabels = (COSDictionary)srcCatalog.getCOSDictionary().getDictionaryObject( pageLabels );
        if( srcLabels != null )
        {
            int destPageCount = destination.getNumberOfPages();
            COSArray destNums = null;
            if( destLabels == null )
            {
                destLabels = new COSDictionary();
                destNums = new COSArray();
                destLabels.setItem( COSName.getPDFName( "Nums" ), destNums );
                destCatalog.getCOSDictionary().setItem( pageLabels, destLabels );
            }
            else
            {
                destNums = (COSArray)destLabels.getDictionaryObject( COSName.getPDFName( "Nums" ) );
            }
            COSArray srcNums = (COSArray)srcLabels.getDictionaryObject( COSName.getPDFName( "Nums" ) );
            for( int i=0; i<srcNums.size(); i+=2 )
            {
                COSNumber labelIndex = (COSNumber)srcNums.getObject( i );
                long labelIndexValue = labelIndex.intValue();
                destNums.add( new COSInteger( labelIndexValue + destPageCount ) );
                destNums.add( cloneForNewDocument( destination, srcNums.getObject( i+1 ) ) );
            }
        }
        
        COSName metadata = COSName.getPDFName( "Metadata" );
        COSStream destMetadata = (COSStream)destCatalog.getCOSDictionary().getDictionaryObject( metadata );
        COSStream srcMetadata = (COSStream)srcCatalog.getCOSDictionary().getDictionaryObject( metadata );
        if( destMetadata == null && srcMetadata != null )
        {
            PDStream newStream = new PDStream( destination, srcMetadata.getUnfilteredStream(), false );
            newStream.getStream().mergeInto( srcMetadata );
            newStream.addCompression();
            destCatalog.getCOSDictionary().setItem( metadata, newStream );
        }

        //finally append the pages
        List pages = source.getDocumentCatalog().getAllPages();
        Iterator pageIter = pages.iterator();
        while( pageIter.hasNext() )
        {
            PDPage page = (PDPage)pageIter.next();
            PDPage newPage = 
                new PDPage( (COSDictionary)cloneForNewDocument( destination, page.getCOSDictionary() ) );
            destination.addPage( newPage );
        }
    }
    Map clonedVersion = new HashMap();
    
    private COSBase cloneForNewDocument( PDDocument destination, Object base ) throws IOException
    {
        if( base == null )
        {
            return null;
        }
        COSBase retval = (COSBase)clonedVersion.get( base );
        if( retval != null )
        {
            //we are done, it has already been converted.
        }
        else if( base instanceof List )
        {
            COSArray array = new COSArray();
            List list = (List)base;
            for( int i=0; i<list.size(); i++ )
            {
                array.add( cloneForNewDocument( destination, list.get( i ) ) );
            }
            retval = array;
        }
        else if( base instanceof COSObjectable && !(base instanceof COSBase) )
        {
            retval = cloneForNewDocument( destination, ((COSObjectable)base).getCOSObject() );
            clonedVersion.put( base, retval );
        }
        else if( base instanceof COSObject )
        {
            COSObject object = (COSObject)base; 
            retval = cloneForNewDocument( destination, object.getObject() );
            clonedVersion.put( base, retval );
        }
        else if( base instanceof COSArray )
        {
            COSArray newArray = new COSArray();
            COSArray array = (COSArray)base;
            for( int i=0; i<array.size(); i++ )
            {
                newArray.add( cloneForNewDocument( destination, array.get( i ) ) );
            }
            retval = newArray;
            clonedVersion.put( base, retval );
        }
        else if( base instanceof COSStream )
        {
            COSStream originalStream = (COSStream)base;
            List keys = originalStream.keyList();
            PDStream stream = new PDStream( destination, originalStream.getFilteredStream(), true );
            clonedVersion.put( base, stream.getStream() );
            for( int i=0; i<keys.size(); i++ )
            {
                COSName key = (COSName)keys.get( i );
                stream.getStream().setItem( key, cloneForNewDocument(destination,originalStream.getItem(key)));
            }
            retval = stream.getStream();
        }
        else if( base instanceof COSDictionary )
        {
            COSDictionary dic = (COSDictionary)base;
            List keys = dic.keyList();
            retval = new COSDictionary();
            clonedVersion.put( base, retval );
            for( int i=0; i<keys.size(); i++ )
            {
                COSName key = (COSName)keys.get( i );
                ((COSDictionary)retval).setItem( key, cloneForNewDocument(destination,dic.getItem(key)));
            }
        }
        else
        {
            retval = (COSBase)base;
        }
        clonedVersion.put( base, retval );
        return retval;
    }

    private int nextFieldNum = 1;
    
    /**
     * Merge the contents of the source form into the destination form 
     * for the destination file.
     * 
     * @param destination the destination document
     * @param destAcroForm the destination form
     * @param srcAcroForm the source form
     * @throws IOException If an error occurs while adding the field.
     */
    private void mergeAcroForm(PDDocument destination, PDAcroForm destAcroForm, PDAcroForm srcAcroForm)
        throws IOException
    {
        List destFields = destAcroForm.getFields();
        List srcFields = srcAcroForm.getFields();
        if( srcFields != null )
        {
            if( destFields == null )
            {
                destFields = new COSArrayList();
                destAcroForm.setFields( destFields );
            }
            Iterator srcFieldsIterator = srcFields.iterator();
            while (srcFieldsIterator.hasNext()) 
            {
                PDField srcField = (PDField)srcFieldsIterator.next();
                PDField destField = 
                    PDFieldFactory.createField( 
                        destAcroForm, 
                        (COSDictionary)cloneForNewDocument(destination, srcField.getDictionary() ));
                // if the form already has a field with this name then we need to rename this field 
                // to prevent merge conflicts.
                if ( destAcroForm.getField(destField.getFullyQualifiedName()) != null ) 
                {
                    destField.setPartialName("dummyFieldName"+(nextFieldNum++));
                }
                destFields.add(destField);
            }
        }
    }
    
}