Howto keep PDF-A when signing a document using IText SignDeferred
问题 I do apply a signature to a pdf document via delayed signing(SignDeferred) using IText. The process contains the following steps: Prepare the pdf document for siging Reserve space for the signature in the pdf document Create the hash value of the pdf document Create the signature based on the hash value Using a self signed certificate Apply the signature to the pdf document The whole process works and i end with a pdf document where the signature is set and is valid. The original pdf is a PDF