Jackson ObjectMapper - specify serialization order of object properties

The following 2 ObjectMapper configuration are required:

ObjectMapper.configure(MapperFeature.SORT_PROPERTIES_ALPHABETICALLY, true)
or
ObjectMapper.enable(MapperFeature.SORT_PROPERTIES_ALPHABETICALLY)

defines the property serialization order used for POJO fields
Note: does not apply to java.util.Map serialization!

and

ObjectMapper.configure(SerializationFeature.ORDER_MAP_ENTRIES_BY_KEYS, true)
or
ObjectMapper.enable(SerializationFeature.ORDER_MAP_ENTRIES_BY_KEYS)

Feature that determines whether java.util.Map entries are first sorted by key before serialization

---

Spring Boot config example (yaml):

spring:
  jackson:
    mapper:
      SORT_PROPERTIES_ALPHABETICALLY: true
    serialization:
      ORDER_MAP_ENTRIES_BY_KEYS: true

The annotations are useful, but can be a pain to apply everywhere. You can configure your whole ObjectMapper to work this way with

Current Jackson versions:

objectMapper.configure(MapperFeature.SORT_PROPERTIES_ALPHABETICALLY, true)

Older Jackson versions:

objectMapper.configure(SerializationConfig.Feature.SORT_PROPERTIES_ALPHABETICALLY, true);

From the Jackson Annotations documentation:

// ensure that "id" and "name" are output before other properties
@JsonPropertyOrder({ "id", "name" })

// order any properties that don't have explicit setting using alphabetic order
@JsonPropertyOrder(alphabetic=true)