Unit testing the creation of an entry in the database

Question

I'm wanted to write a simple unit test for a service. This is the method in my service which I want to unitest.

@Log4j
@Service
public class Service {

     @Autowired
     private Repository repository;

    public JpaRecord create(JpaRecord jpaRecord) {
        return repository.save(jpaRecord);
    }
}

This method just creates a new entry in the Database.

This is the JpaRecord:

@Data
@Entity
@Table(name = "TEST", schema = "TEST")
public class JpaRecord implements Serializable {
    private static final long serialVersionUID = 1L;

    JpaRecord() {
        // default constructor
    }

    public JpaRecord(
            String name,
            Date createdAt,
            Blob file
    ) {
        this.name = name;
        this.createdAt = createdAt;
        this.file = file;
    }

    @Id
    @Column(name = "ID", nullable = false)
    @GeneratedValue(strategy = GenerationType.SEQUENCE,
            generator = "TEST_SEQx")
    @SequenceGenerator(
            sequenceName = "TEST_SEQ", allocationSize = 1,
            name = "TEST_SEQx")
    private Long id;

    @Column(name = "NAME")
    private String name;

    @Temporal(TemporalType.TIMESTAMP)
    @Column(name = "CREATED_AT")
    private Date createdAt;

    @Lob
    @Column(name = "FILE")
    private Blob file;
}

The id should not be null, all the other entries can be null. I wrote this test to check if the DB entry is not null, which means it is created.

public class ServiceTest {

    @Autowired
    private Service Service;

    @Autowired
    private JpaRecord JpaRecord;

    @Before
    public void setUp(){

    }

    @Test
    public void testCreateWhenNull(){
        // prepare data
        JpaRecord = new JpaRecord("testProject", new Date(),null);
        // run

        // test with assert
        Assert.assertNotNull(Service.create(JpaRecord));
    }

}

I then get a java.lang.NullPointerException. I would really appreciate any suggestion on how I should approach a problem to unit test it. It is my first time unit testing and I wanted to start with a simple null check.

Answer 1

you are missing some configuration related spring boot JUnit testing at the class level that's why you are getting Nullpointer Exception.please read the following link reference link