Avoid object with null fields using Jackson

Question

If I try to deserialize a JSON string that is missing a field from the object class, that field is set to null when the object is created. I need Jackson to throw an exception when this happens so I don't have to implement an assertNotNullFields() method in every object; i.e the JSON string input must have defined all the fields in the class or a JsonProcessingException is thrown.

Object mapper configuration:

objectMapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.NONE);
objectMapper.setVisibility(PropertyAccessor.FIELD, JsonAutoDetect.Visibility.ANY);

JSON object:

public class LogInUser {
    public String identifier, password;
    public LogInUser() {}
}

Is this possible given my configuration?

score 1 · Accepted Answer · edited May 23 '17 at 12:02

You could try using JsonCreator within your LogInUser class as mentioned here. When introduced into the code you posed in your quesion, it would look something like this:

public class LogInUser {

    @JsonCreator
    public LogInUser(@JsonProperty(value = "identifier", required = true) String identifier, @JsonProperty(value = "password", required = true) String password) {
    this.identifier = identifier;
    this.password = password;
    }

    public String identifier, password;
    public LogInUser() {}

}

When one or more of the values are null, it should throw an exception.

Avoid object with null fields using Jackson

1 Answers1