JarCastingJacksonatic
A fluent api to define Jackson mapping programmatically in order to avoid polluting domain code with annotations.
Goal
If you are concerned by the DDD (Domain Driver Design), or just, the isolation between the business code and technical code, or simply, the overuse of annotations, Jacksonatic can help you.
Jackson offers you one way to separate the mapping annotations adn the mapped class with the mix-in, but you to define one mix-in class by mapped class.
With Jacksonatic, you can define all your application mapping in one shot with a fluent api. You can add jackson annotations programmatically on your domain classes in a separated initialization code.
Moreover you have somme extra-feature to facilitate your mapping :
- Map or ignore a field or a method
- Map or ignore a method
- Map or ignore a getter or a setter
- Map a constructor or a static factory for the deserialization (respect encapsulation)
- Auto-detect a constructor or a static factory for the deserialization
- Use the inheritance to propagate the mapping
- Facilitate the polymorphism mapping
Build status
Setup (Maven)
You can add Jacksonatic as a maven dependency of your project. Jacksonatic requires java 8.
<dependency>
<groupId>com.github.mrenou</groupId>
<artifactId>jacksonatic</artifactId>
<version>0.3</version>
</dependency>
Examples
Add @JsonProperty on a field and @JsonIgnore on a method
import static com.github.mrenou.jacksonatic.Jacksonatic.configureMapping;
import static com.github.mrenou.jacksonatic.annotation.JacksonaticJsonIgnore.jsonIgnore;
import static com.github.mrenou.jacksonatic.annotation.JacksonaticJsonProperty.jsonProperty;
import static com.github.mrenou.jacksonatic.mapping.ClassMapping.type;
import static com.github.mrenou.jacksonatic.mapping.FieldMapping.field;
import static com.github.mrenou.jacksonatic.mapping.MethodMapping.method;
configureMapping()
.on(type(Pojo.class)
.on(field("field1").add(jsonProperty())))
.on(method("field2").add(jsonIgnore())))
.registerIn(objectMapper);
Add JsonIgnoreProperties to ignore unknown properties on a class
import static com.github.mrenou.jacksonatic.Jacksonatic.configureMapping;
import static com.github.mrenou.jacksonatic.annotation.JacksonaticJsonIgnoreProperties.jsonIgnoreProperties;
import static com.github.mrenou.jacksonatic.mapping.ClassMapping.type;
configureMapping()
.on(type(Pojo.class)).add(jsonIgnoreProperties().ignoreUnknown())
.registerIn(objectMapper);
Map a field
import static com.github.mrenou.jacksonatic.Jacksonatic.configureMapping;
import static com.github.mrenou.jacksonatic.mapping.ClassMapping.type;
configureMapping()
.on(type(Pojo.class)
.mapA("field1"))
.registerIn(objectMapper);
Shortcut to add @JsonProperty on field named "field1".
Map several types
import static com.github.mrenou.jacksonatic.Jacksonatic.configureMapping;
import static com.github.mrenou.jacksonatic.mapping.ClassMapping.type;
configureMapping()
.on(type(Pojo1.class)
.mapAll())
.on(type(Pojo2.class)
.mapAll())
.registerIn(objectMapper);
Shortcut to add @JsonProperty on all fields for types "Pojo1" and "Pojo2".
Use inheritance to map several types
import static com.github.mrenou.jacksonatic.Jacksonatic.configureMapping;
import static com.github.mrenou.jacksonatic.mapping.ClassMapping.type;
configureMapping()
.on(type(Object.class)
.mapAll())
.registerIn(objectMapper);
As all types inherit Object type, so add @JsonProperty on all fields of all types.
Map all field expect one
import static com.github.mrenou.jacksonatic.Jacksonatic.configureMapping;
import static com.github.mrenou.jacksonatic.mapping.ClassMapping.type;
configureMapping()
.on(type(Pojo.class)
.mapAll()
.ignore("field2"))
.registerIn(objectMapper);
Shortcut to add @JsonProperty on all fields and @JsonIgnore on field named "field2".
Map a getter and a setter
import static com.github.mrenou.jacksonatic.Jacksonatic.configureMapping;
import static com.github.mrenou.jacksonatic.mapping.ClassMapping.type;
configureMapping()
.on(type(Pojo.class)
.mapGetter("field1")
.mapSetter("field1"))
.registerIn(objectMapper);
Shortcut to add @JsonProperty on methods "getField1" and "setField1".
Map a constructor
import static com.github.mrenou.jacksonatic.Jacksonatic.configureMapping;
import static com.github.mrenou.jacksonatic.mapping.ClassMapping.type;
configureMapping()
.on(type(Pojo.class)
.withConstructor(matchType(String.class), matchType(Integer.class)))
.registerIn(objectMapper);
Shortcut to add @JsonCreator on tje constructor with parametric signature (String, Integer).
Map a static factory
import static com.github.mrenou.jacksonatic.Jacksonatic.configureMapping;
import static com.github.mrenou.jacksonatic.mapping.ClassMapping.type;
import static com.github.mrenou.jacksonatic.mapping.ParameterCriteria.matchType;
configureMapping()
.on(type(Pojo.class)
.onStaticFactory("build" matchType(String.class), matchType(Integer.class)))
.registerIn(objectMapper);
Shortcut to add @JsonCreator on the static method named "build" with parametric signature (String, Integer). Add also @JsonProperty on parameters using class fields to set the json property names.
Map constructor or static factory automatically
import static com.github.mrenou.jacksonatic.Jacksonatic.configureMapping;
import static com.github.mrenou.jacksonatic.mapping.ClassMapping.type;
configureMapping()
.on(type(Pojo.class)
.withAConstructorOrStaticFactory())
.registerIn(objectMapper);
Try to find a constructor with a parametric signature having same types (or less) than the types of class fields, ignoring static fields. If no constructor is found with all field types, try to find a static factory with the same algorithm. The constructor is used if a constructor and a static factory match same field types.
Map polymorphism
import static com.github.mrenou.jacksonatic.Jacksonatic.configureMapping;
import static com.github.mrenou.jacksonatic.mapping.ClassMapping.type;
configureMapping()
.on(type(PojoParent.class)
.fieldForTypeName("type")
.addNamedSubType(PojoChild1.class, "CHILD1")
.addNamedSubType(PojoChild2.class, "CHILD2")
.withAConstructorOrStaticFactory())
.registerIn(objectMapper);
Shortcut to add @JsonTypeInfo and @JsonSubTypes on parent class, and also @JsonTypeName on children classes.