How to tell Jackson to ignore a field during serialization if its value is null?

Question

How can Jackson be configured to ignore a field value during serialization if that field\'s value is null.

For example:

public class SomeClass {
            


        

Answer 1

For Jackson 2.5 use :

@JsonInclude(content=Include.NON_NULL)

Answer 2

This has been troubling me for quite some time and I finally found the issue. The issue was due to a wrong import. Earlier I had been using

com.fasterxml.jackson.databind.annotation.JsonSerialize

Which had been deprecated. Just replace the import by

import org.codehaus.jackson.map.annotate.JsonSerialize;
import org.codehaus.jackson.map.annotate.JsonSerialize.Inclusion;

and use it as

@JsonSerialize(include=Inclusion.NON_NULL)

Answer 3

To suppress serializing properties with null values using Jackson >2.0, you can configure the ObjectMapper directly, or make use of the @JsonInclude annotation:

mapper.setSerializationInclusion(Include.NON_NULL);

or:

@JsonInclude(Include.NON_NULL)
class Foo
{
  String bar;
}

Alternatively, you could use @JsonInclude in a getter so that the attribute would be shown if the value is not null.

A more complete example is available in my answer to How to prevent null values inside a Map and null fields inside a bean from getting serialized through Jackson.

Answer 4

If in Spring Boot, you can customize the jackson ObjectMapper directly through property files.

Example application.yml:

spring:
  jackson:
    default-property-inclusion: non_null # only include props if non-null

Possible values are:

always|non_null|non_absent|non_default|non_empty

More: https://docs.spring.io/spring-boot/docs/current/reference/html/howto-spring-mvc.html#howto-customize-the-jackson-objectmapper

Answer 5

We have lot of answers to this question. This answer may be helpful in some scenarios If you want to ignore the null values you can use the NOT_NULL in class level. as below

@JsonInclude(Include.NON_NULL)
class Foo
{
  String bar;
}

Some times you may need to ignore the empty values such as you may have initialized the arrayList but there is no elements in that list.In that time using NOT_EMPTY annotation to ignore those empty value fields

@JsonInclude(Include.NON_EMPTY)
class Foo
{
  String bar;
}

Answer 6

Global configuration if you use Spring

@Configuration
public class JsonConfigurations {

    @Bean
    public Jackson2ObjectMapperBuilder objectMapperBuilder() {
        Jackson2ObjectMapperBuilder builder = new Jackson2ObjectMapperBuilder();
        builder.serializationInclusion(JsonInclude.Include.NON_NULL);
        builder.serializationInclusion(JsonInclude.Include.NON_EMPTY);
        builder.failOnUnknownProperties(false);
        return builder;
    }

}