Free Support Forum -

Compare construction plans in vector PDF format using Java


we operate and develop a java-based application and are currently evaluating certain libraries/products for future features.

One specific requirement is to compare 2 construction plans which are in vector PDF format (originally converted from AutoCAD dwg files, which we do not have). The goal is to produce a PDF where differences (lines, texts) are highlighted in certain colors.

Is this possible with GroupDocs.Comparison for Java?
If yes, are there any examples on what the result of such a comparison would look like?



Thanks for taking interest in GroupDocs.Comparison for Java and posting your concerns.

Please note that GroupDocs.Comparison for Java is a back-end, UI-independent API that can be integrated in any Java application.
It is a one-stop solution for comparing documents of supported formats.

Yes, you can compare supported documents and get comparison summary. Furthermore, if there is a change found, you can highlight it. For instance, an inserted item style change can be highlighted as follows:


You may find the following resources helpful:

API Homepage
PDF Comparison
GitHub Examples

Please go through the source, target and output documents (as a sample) - (29.0 KB)

Thanks for your reply. However this does not answer the specific question if vector graphics in pdfs, such a plans can be compared/highlighted as well (not only text).

Has anyone here maybe already tried that or has experience in this area (searching the forum i could not find anything)



Please note that API supports dwg files comparison.

However, we are investigating this scenario. Your investigation ticket ID is COMPARISONJAVA-446. We shall update you as we have any update. Can you please further share a sample file with us?


i understand that dwg files are supported - sadly the exchange format is pdf.

Here are 2 plans which are slightly different:
plan1.pdf (951.8 KB)
plan2.pdf (986.2 KB)

Due to attachment size limit, please find in the next post a PNG image of what a result could look like. We converted the vector pdfs to png images and made a pixel by pixel compare. the result is ok, but not ideal (large file sizes, high cpu load to compare and of course it’s pixelated)

Thanks again for your help on this matter.

here the raster comparison png:
difference-plan1-2.jpg (1.4 MB)


Thanks for sharing the concerned files.
We are looking into the possibility, if this requirement could be achieved using GroupDocs.Comparison for Java. As we have any update, we shall notify you.


Comparison of construction plans which are in vector PDF format is not supported in current version of GroupDocs.Comparison for Java.
However, we’ll see if this feature could be added in any of the future release.


thanks for your help :slight_smile:

1 Like


You are welcome.