Question

I have the following class:

@Entity
@Table(name = "USERS")
public class User {

    private Long userID;

    @Id
    @Column(name = "userID")
    @GeneratedValue(generator = "increment")
    @GenericGenerator(name = "increment", strategy = "increment")
    public Long getUserID() {
        return userID;
    }

    @Column(nullable = false)
    private boolean isActive;

    @Column(nullable = false, unique = true)
    private String email;

    @Column(nullable = false)
    private String password;


    @Column
    @Temporal(TemporalType.TIMESTAMP)
    private Calendar lastLoggedIn;

    @Column(nullable = false)
    @Temporal(TemporalType.TIMESTAMP)
    private Calendar createdDate;

    @Version
    private Integer version;

    public String getEmail() {
        return email;
    }

    public boolean isActive() {
        return isActive;
    }

    public void setActive(boolean isActive) {
        this.isActive = isActive;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public Calendar getLastLoggedIn() {
        return lastLoggedIn;
    }

    public void setLastLoggedIn(Calendar lastLoggedIn) {
        this.lastLoggedIn = lastLoggedIn;
    }

    public Calendar getCreatedDate() {
        return createdDate;
    }

    public void setCreatedDate(Calendar createdDate) {
        this.createdDate = createdDate;
    }

    public Integer getVersion() {
        return version;
    }

    public void setVersion(Integer version) {
        this.version = version;
    }

    public void setUserID(Long userID) {
        this.userID = userID;
    }

    public User(Long userID, String email, String password, Calendar lastLoggedIn, Calendar createdDate, Integer version) {

    }

    // No argument constructor
    public User() {}
}

When I run my application, Hibernate loads the configuration and creates the table for Users. I’m using Postgresql. This is the SQL statement being generated (logged by hibernate):

Hibernate: create table USERS 
           (userID int8 not null, active boolean not null, createdDate timestamp, 
            email varchar(255), lastLoggedIn timestamp, 
            password varchar(255), version int4, primary key (userID))

Why is it that a boolean is created as not null and a String/Timestamp is not? I won’t there to be an exception if you try to insert a User without an email or password, but with this generated schema it won’t. Is there another way to force Hibernate to create the field as not nullable?

Answer 1

From 5.1.4.1.2. Access type :

By default the access type of a class hierarchy is defined by the
position of the @Id or @EmbeddedId annotations. If these annotations
are on a field, then only fields are considered for persistence and
the state is accessed via the field. If there annotations are on a
getter, then only the getters are considered for persistence and the
state is accessed via the getter/setter.

As you annotate @Id on the getter , you are using property access. So , hibernate will ignore all mapping annotations marked on the fields and only use annotations on getters to generate DDL . Because there are no annotations on getters , default settings are used .

You should get your desired result if you change to annotate @Id on the userID instead of getUserID()