How Jackson ObjectMapper Matches JSON Fields to Java Fields To read Java objects from JSON with Jackson properly, it is important to know how Jackson maps the fields of a JSON object to the fields of a Java object, so I will explain how Jackson does that.
By default Jackson maps the fields of a JSON object to fields in a Java object by matching the names of the JSON field to the getter and setter methods in the Java object. Jackson removes the "get" and "set" part of the names of the getter and setter methods, and converts the first character of the remaining name to lowercase.
For instance, the JSON field named brand matches the Java getter and setter methods called getBrand() and setBrand(). The JSON field named engineNumber would match the getter and setter named getEngineNumber() and setEngineNumber().
If you need to match JSON object fields to Java object fields in a different way, you need to either use a custom serializer and deserializer, or use some of the many Jackson Annotations.
