java - Spring Data JPA 用户帖子

Question

我有用户登录和个人资料 View ，我希望用户有帖子。有人可以引导我走向正确的方向吗？

我有一个用户实体:

    @Entity
@Table(name = "usr", indexes = { @Index(columnList = "email", unique = true) })
// using usr because in may conflict with the name of the class
public class User {

    public static final int EMAIL_MAX = 250;
    public static final int NAME_MAX = 50;

    /*
     * public static enum Role {
     * 
     * UNVERIFIED, BLOCKED, ADMINISTRATOR
     * 
     * }
     */

    // primary key long, needs to be annotated with @Id
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private long id;

    // add columns
    @Column(nullable = false, length = EMAIL_MAX)
    private String email;

    @Column(nullable = false, length = NAME_MAX)
    private String name;

    // no length, the password will be encrypted to some longer value than the
    // user enters
    @Column(nullable = false)
    private String password;

    /*
     * //email verification code
     * 
     * @Column(length = 16) private String verificationCode;
     * 
     * public String getVerificationCode() { return verificationCode; }
     * 
     * public void setVerificationCode(String verificationCode) {
     * this.verificationCode = verificationCode; }
     * 
     * 
     * @ElementCollection(fetch = FetchType.EAGER) private Set<Role> roles = new
     * HashSet<Role>();
     * 
     * 
     * 
     * public Set<Role> getRoles() { return roles; }
     * 
     * public void setRoles(Set<Role> roles) { this.roles = roles; }
     */

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public String getEmail() {
        return email;
    }

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

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPassword() {
        return password;
    }

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

    public boolean isEditable() {
        User loggedIn = MyTools.getSessionUser();

        if (loggedIn == null) {
            return false;
        }

        return loggedIn.getId() == id;
    }

}

和仓库:

    public interface UserRepository extends JpaRepository<User, Long> {

    // @Query("select u from User u where u.email = ?1")
    User findByEmail(String email);

}

现在，为了让该用户发布帖子，我是否在 post pojo 中使用 @manytoone 创建一个帖子实体和存储库？我最终想创建一个推特，但首先我必须让用户发帖。如果您知道解释这一点的好教程，那就太好了。

Answer 1

创建第二个实体(java 类)，例如用户帖子:

@Entity
@Table(...)
public class UserPost {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private long id;

    private long userId;

    ...
}

然后将@OneToMany关系字段添加到User。级联、延迟加载等取决于您如何使用它。 User 内部看起来像这样:

@OneToMany(cascade={...})
@JoinColumn(name="userId")
private Set<UserPost> posts;