Getting NullPointerExpception while Using JDBI

[Viraj Trivedi]

Please help me,

I am a newbie at DropWizard and I want to Use DropWizard with JDBI, I have 
created DAO and Resources as Documentation guides but I'm getting a 
NullPointerException every time.

Please guide me through the correct way of implementing JDBI.


Attached the Files which I've coded

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import org.skife.jdbi.v2.sqlobject.Bind;
import org.skife.jdbi.v2.sqlobject.BindBean;
import org.skife.jdbi.v2.sqlobject.SqlQuery;
import org.skife.jdbi.v2.sqlobject.SqlUpdate;
import org.skife.jdbi.v2.sqlobject.customizers.RegisterMapper;

import java.util.List;

/**
 * Created by viraj on 01-02-2017.
 */
@RegisterMapper(PersonMapper.class)
public interface PersonDAO {

    @SqlQuery("select * from PERSON")
    List<Person> getAll();

    @SqlQuery("select * from PERSON where ID = :id")
    Person findById(@Bind("id") int id);

    @SqlUpdate("delete from PERSON where ID = :id")
    int deleteById(@Bind("id") int id);

    @SqlUpdate("update PERSON set NAME = :name where ID = :id")
    int update(@BindBean Person person);

    @SqlUpdate("insert into PERSON (ID, NAME) values (:id, :name)")
    int insert(@BindBean Person person);
}
import org.skife.jdbi.v2.StatementContext;
import org.skife.jdbi.v2.tweak.ResultSetMapper;

import java.sql.ResultSet;
import java.sql.SQLException;

public class PersonMapper implements ResultSetMapper<Person>
{
    public Person map(int index, ResultSet resultSet, StatementContext statementContext) throws SQLException
    {
        return new Person(resultSet.getInt("ID"), resultSet.getString("NAME"));
    }
}

import javax.validation.Valid;
import javax.ws.rs.*;
import javax.ws.rs.core.MediaType;
import java.util.List;

@Path("/person")
@Consumes({MediaType.APPLICATION_JSON})
@Produces({MediaType.APPLICATION_JSON})
public class PersonResource {

    PersonDAO personDAO;

    public PersonResource(PersonDAO personDAO) {
        this.personDAO = personDAO;
    }

    @GET
    @Path("/xxx")
    public List<Person> gety(){
        return personDAO.getAll();
    }
    @GET
    public List<Person> getAll(){
        return personDAO.getAll();
    }

    @GET
    @Path("/{id}")
    public Person get(@PathParam("id") Integer id){
        return personDAO.findById(id);
    }

    @POST
    public Person add(@Valid Person person) {
        personDAO.insert(person);

        return person;
    }

    @PUT
    @Path("/{id}")
    public Person update(@PathParam("id") Integer id, @Valid Person person) {
        Person updatePerson = new Person(id, person.getName());

        personDAO.update(updatePerson);

        return updatePerson;
    }

    @DELETE
    @Path("/{id}")
    public void delete(@PathParam("id") Integer id) {
        personDAO.deleteById(id);
    }
}

import io.dropwizard.setup.Bootstrap;
import io.dropwizard.setup.Environment;
import io.dropwizard.jdbi.DBIFactory;
import org.skife.jdbi.v2.DBI;

public class Application extends io.dropwizard.Application<Configuration> {
    public static void main(String[] args) throws Exception {
        new Application().run(args);
    }

    @Override
    public String getName() {
        return "dropwizard-jdbi";
    }

    @Override
    public void initialize(Bootstrap<Configuration> bootstrap) {
    }

    @Override
    public void run(Configuration configuration, Environment environment) throws ClassNotFoundException {
        final DBIFactory factory = new DBIFactory();
        final DBI jdbi = factory.build(environment, configuration.getDataSourceFactory(), "maria");

        final PersonDAO personDAO = jdbi.onDemand(PersonDAO.class);
        final PersonResource personResource = new PersonResource(personDAO);

        environment.jersey().register(personResource);
    }
}
import com.fasterxml.jackson.annotation.JsonProperty;
import io.dropwizard.db.DataSourceFactory;

import javax.validation.Valid;
import javax.validation.constraints.NotNull;

/**
 * Created by viraj on 01-02-2017.
 */
public class Configuration extends io.dropwizard.Configuration{


    @Valid
    @NotNull
    @JsonProperty("database")
    private DataSourceFactory database = new DataSourceFactory();

    public DataSourceFactory getDataSourceFactory() {
        return database;
    }
}

import com.fasterxml.jackson.annotation.JsonProperty;

import javax.validation.constraints.NotNull;

public class Person {

    @NotNull
    @JsonProperty
    private Integer id;

    @NotNull
    @JsonProperty
    private String name;

    public Person() {
        // Jackson deserialization
    }

    public Person(int id, String name) {
        this.id = id;
        this.name = name;
    }

    public Integer getId() {
        return id;
    }

    public String getName() {
        return name;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (!(o instanceof Person)) return false;

        Person that = (Person) o;

        if (!getId().equals(that.getId())) return false;
        if (!getName().equals(that.getName())) return false;

        return true;
    }
}