Question

any way to store json data in multichain1.0 directly or to convert json data to hex directly using multichain javaapi

Answer 1

No, MultiChain 1.0 does not have built-in support for JSON data. However you can use any JSON serialization library to convert the JSON to binary data, then send that in hexadecimal to MultiChain's APIs, then do the reverse conversion when reading. MultiChain 2.0 uses the UBJSON serialization format described at http://ubjson.org/