Java Objects to create JSON certificate file

Hi all,

As a newbie, I struggled to run the docker image and the python program to create a valid certificate and to understand each block of data. It took me a while to understand that anchoring the merkle root in a blockchain is optional. This easy to use code simply creates the JSON file that passes remote validation. Also I did not find a Java project with POJOs for all JSON elements, so I created one. This also uses URDNA2015 for JSON-LD so that the SHA-256 created matches with python and js.

Hence, I created a simple Java program with java objects for each block that can be easily converted into final JSON.


Build a JSON file in Java using java objects, use default input data, generate local hash and build signature block. Pass remote validation in by inputting the generated json file.


  • git clone/Download
  • import/open project in Eclipse
  • go to file
  • “Run” as Java application
  • Output JSON file will be created in the eclipse-workspace project directory and filename will be shown in the console
  • go to in the browser
  • Click choose json file and pick the newly created .json file
  • blockcerts will show “This Mocknet credential passed all checks”
  • That’s it. Change the default values and see how it affects validation
1 Like


I tried this but getting com.nbouma.jsonldjava.core.JsonLdError: loading remote context failed:,https:/
at com.nbouma.jsonldjava.core.DocumentLoader.loadDocument(