This project contains multiple examples using the jackson annotations for parsing java objects to json.
Each example contains the definition of the java class and a test where the object is converted to json and vice versa.
Simple example with no annotations.
Jackson needs an empty constructor.
The methods (getters, setters, etc) and the empty constructor used by jackson can have any visibility (private, package, protected and public).
Example that shows how to define a one way serialization.
Example that shows how to ignore a property during.
Example that shows how to rename a property during serialization, deserialization or both.
IMPORTANT The annotation @JsonGetter allow us to rename a field for the serialization, it requires a @JsonSetter for the same field, otherwise the name is changed in bot, serialization and deserialization.
Example that shows how to avoid cyclic serialization issues.
Example that shows how to avoid cyclic serialization issues when we are serializing/deserializing a set of objects with an owner part.
Example that shows how to serialize and deserialize dynamic attributes.
Example that shows how to serialize objects that contains json attributes in String fields.
IMPORTANT The annotation @JsonRawValue is only for serialization (object to json), if we need the opposite we can use the @JsonProperty in a setter method.
Example that shows how to add another level in the json with the name of the root class when serializing.
IMPORTANT To achieve this functionality, we need to enable the options in te ObjectMapper instance (WRAP_ROOT_VALUE and UNWRAP_ROOT_VALUE).
Example that shows how to serialize and deserialize objects with multiple levels of polymorphism.
Multiple fields for type are not supported.
IMPORTANT Whe need to define the type of the parent class in both places when multiple levels are defined.
Example that shows how to serialize and deserialize objects with nested objects to flat json.
IMPORTANT The prefix and suffix don't do any capitalization to the names.
Example that shows how to serialize and deserialize the classes of the java.time library, it shows how to use the default formats and custom formats.
IMPORTANT We need to register the JavaTimeModule in the ObjectMapper instance. Additionally, we need to disable the property WRITE_DATES_AS_TIMESTAMPS to disable the conversion of the objects to milliseconds.
Example that shows how to serialize and deserialize the classes of the joda.time library, it shows how to use the default formats and custom formats.
IMPORTANT We need to register the JodaTimeModule in the ObjectMapper instance. Additionally, we need to disable the property WRITE_DATES_AS_TIMESTAMPS to disable the conversion of the objects to milliseconds.
VERY IMPORTANT Note that from Java SE 8 onwards, users are asked to migrate to java.time (JSR-310) - a core part of the JDK which replaces Joda-Time