How do I disable fail_on_empty_beans in Jackson?

Question

You can do this per class or globally, I believe.

For per class, try @JsonSerialize above class declaration.

For a mapper, here's one example:

ObjectMapper mapper = new ObjectMapper();
mapper.configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false);
// do various things, perhaps:
String someJsonString = mapper.writeValueAsString(someClassInstance);
SomeClass someClassInstance = mapper.readValue(someJsonString, SomeClass.class)

The StackOverflow link below also has an example for a Spring project.

For REST with Jersey, I don't remember off the top off my head, but I believe it's similar.

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Couple of links I dug up: (edited 1st link due to Codehaus shutting down).

• https://web.archive.org/web/20150513164332/https://jira.codehaus.org/browse/JACKSON-201
• Jackson serializationConfig

If you are using Spring Boot, you can set the following property in application.properties file. spring.jackson.serialization.FAIL_ON_EMPTY_BEANS=false

You can also get the same issue if your class doesn't contain any public methods/properties. I normally have dedicated DTOs for API requests and responses, declared public, but forgot in one case to make the methods public as well - which caused the "empty" bean in the first place.

If you wish to get JSON object without any extra fields - please add this annotation to your class, it worked perfect for me.

@JsonIgnoreProperties({"hibernateLazyInitializer", "handler"})

You can also add in your application.properties file this row, but it will add an extra field to your JSON.

spring.jackson.serialization.FAIL_ON_EMPTY_BEANS=false