JsonFormat int64 converting

[z0mb1ek]

Hi. Why int64(long in java) convert to string?

case INT64:       
case SINT64:
case SFIXED64:
          generator.print("\"" + ((Long) value).toString() + "\"");
          break;

[xfxyjwf]

It's required by proto3 JSON spec:
https://developers.google.com/protocol-buffers/docs/proto3#json

It's because int64 is not a standard JSON type and many JSON parsers don't support int64 precision. To avoid precision loss for int64, we decided to print int64 as strings in proto3 JSON.