Cannot construct instance of - Jackson

You need to use a concrete class and not an Abstract class while deserializing. if the Abstract class has several implementations then, in that case, you can use it as below-

  @JsonTypeInfo( use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.PROPERTY, property = "type")
    @JsonSubTypes({ 
      @Type(value = Bike.class, name = "bike"), 
      @Type(value = Auto.class, name = "auto"), 
      @Type(value = Car.class, name = "car")
    })
    public abstract class Vehicle {
        // fields, constructors, getters, setters
    }

You cannot instantiate an abstract class, Jackson neither. You should give Jackson information on how to instantiate MyAbstractClass with a concrete type.

See this answer on stackoverflow: Jackson JSON library: how to instantiate a class that contains abstract fields

And maybe also see Jackson Polymorphic Deserialization

Tags:

Java

Jackson