import org.codehaus.jackson.map.ObjectMapper

class User 
{
    static class Name{
        String first;
        String last;
    }
    
    Name name
    Boolean verified
    String gender
    byte[] userImage
}

String json = """{
  "name" : { "first" : "Joe", "last" : "Sixpack" },
  "gender" : "MALE",
  "verified" : false,
  "userImage" : "Rm9vYmFyIQ=="
}
"""

ObjectMapper mapper = new ObjectMapper(); 
User user = mapper.readValue(json, User.class);

assert user.name.first == "Joe"
assert user.name.last == "Sixpack"
assert user.gender == "MALE"
assert user.verified == false
assert user.userImage.size() == 7

Make sure Jackson core and Mappers are on classpath. So who can explain why userImage has a size of 7. I assume the byte-Array is encoded. What format?

Jackson Demo from Groovy Console

groovy, json

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