Difference between revisions of "Jackson examples"

package andy.jackson.demo.model.impl;

import andy.jackson.demo.model.Family;
import andy.jackson.demo.model.Person;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;

import java.util.ArrayList;
import java.util.List;

public class FamilyImpl implements Family {
    /*
        As the interface (andy.jackson.demo.model.Family) requires we emit a List of andy.jackson.demo.model.Person (another interface), we
        make use the JsonDeserialize annotation to tell Jackson to create the list using the PersonImpl concrete implementation class.
     */
    @JsonDeserialize(as=List.class,contentAs=PersonImpl.class)
    private List<Person> people = new ArrayList<>();
    private String surname;

    @Override
    public List<Person> getPeople() {
        return people;
    }

    public void setPeople(List<Person> people) {
        this.people = people;
    }

    @Override
    public String getSurname() {
        return surname;
    }

    public void setSurname(String surname) {
        this.surname = surname;
    }
}

    /**
     * Note the JsonDeserialize annotation against the 'people' property in the FamilyImpl class. It tells Jackson to use a List of PersonImpl.
     *
     * @throws IOException
     */
    @Test
    public void testDeserialize() throws IOException {
        String json = "{\"people\":[{\"name\":\"Fred\",\"age\":55}],\"surname\":\"Smith\"}";
        ObjectMapper om = new ObjectMapper();
        Family family = om.readValue( json , FamilyImpl.class );
        Assert.assertEquals( "Smith" , family.getSurname() );
        Assert.assertEquals( 1 , family.getPeople().size() );
        Assert.assertEquals( 55 , family.getPeople().get(0).getAge() );
        Assert.assertEquals( "Fred" , family.getPeople().get(0).getName() );
    }