将外部标识映射到本地标识

Question

在我的应用中，用户可以将电影添加到他们的监视列表中。电影数据来自外部API。每部电影都有自己独特的身份证。例如：Star Wars - A new hope标识为11。 Fight Club的标识为550。

当用户添加电影时，我将整个电影对象从前端传递到后端：

组件：

createMovie(movie: Movie): void {
  this._dataService.createMovie<Movie>({'name': 'Star Wars - A new hope', 'id': 11})
  .subscribe((data) => this.movies.push(data),
  error => () => {
      'something went wrong';
  },
  () => {
      // console.log(this.movies);
  });
}

在这种情况下，我使用了示例数据。

服务：

public createMovie<T>(movie: Movie): Observable<T> {
    return this.http.post<T>('/api/movies/', movie, {headers: this.getToken()});
}

后端的MovieController：

@RequestMapping(value = "/", method = RequestMethod.POST)
public Movie createMovie(@RequestBody Movie movie){
    return movieService.createMovie(movie);
}

MovieService：

@Override 
public Movie createMovie(Movie movie) {

    User current_user = userService.getUser();
    current_user.addMovie(movie);
    userRepository.save(current_user);

    return movie;
}

用户模型：

public void addMovie(Movie movie) {
    movies.add(movie);
    movie.getUsers().add(this);
}

当电影保存在数据库中时，它以唯一的id保存，从1开始。如何将ID从前端映射到数据库中对象的id？我可以创建另一个列＆＃34; external_id＆＃34;并将其映射到那个，但我认为这不是使用外部API中的id的解决方案。

//编辑。添加了我的电影和用户模型：

package com.movieseat.models;

import com.movieseat.model.security.User;
import java.util.HashSet;
import java.util.Set;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.ManyToMany;
import javax.persistence.Table;

@Entity(name = "Movie")
@Table(name = "movie")
public class Movie {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "id")
    private Integer id;
    private String name;
    private String description;

    @ManyToMany(mappedBy = "movies")
    private Set<User> users = new HashSet<>(); 

    public Set<User> getUsers() {
        return users;
    }

    public void setUsers(Set<User> users) {
        this.users = users;
    }

    public Integer getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

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

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

}

用户模型：

package com.movieseat.model.security;

import javax.persistence.*;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;
import com.fasterxml.jackson.annotation.JsonIdentityInfo;
import com.fasterxml.jackson.annotation.ObjectIdGenerators;
import com.movieseat.models.Movie;
import java.util.Date;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

@Entity(name = "User")
@Table(name = "USER")
@JsonIdentityInfo(generator=ObjectIdGenerators.PropertyGenerator.class, property="id")
public class User {

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

    @Column(name = "USERNAME", length = 50, unique = true)
    @NotNull
    @Size(min = 4, max = 50)
    private String username;

    @Column(name = "PASSWORD", length = 100)
    @NotNull
    @Size(min = 4, max = 100)
    private String password;

    @Column(name = "FIRSTNAME", length = 50)
    @NotNull
    @Size(min = 4, max = 50)
    private String firstname;

    @Column(name = "LASTNAME", length = 50)
    @NotNull
    @Size(min = 4, max = 50)
    private String lastname;

    @Column(name = "EMAIL", length = 50)
    @NotNull
    @Size(min = 4, max = 50)
    private String email;

    @Column(name = "ENABLED")
    @NotNull
    private Boolean enabled;

    @Column(name = "LASTPASSWORDRESETDATE")
    @Temporal(TemporalType.TIMESTAMP)
    @NotNull
    private Date lastPasswordResetDate;

    @ManyToMany(fetch = FetchType.EAGER)
    @JoinTable(
            name = "USER_AUTHORITY",
            joinColumns = {@JoinColumn(name = "USER_ID", referencedColumnName = "ID")},
            inverseJoinColumns = {@JoinColumn(name = "AUTHORITY_ID", referencedColumnName = "ID")})
    private List<Authority> authorities;

    public Long getId() {
        return id;
    }

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

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

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

    public String getFirstname() {
        return firstname;
    }

    public void setFirstname(String firstname) {
        this.firstname = firstname;
    }

    public String getLastname() {
        return lastname;
    }

    public void setLastname(String lastname) {
        this.lastname = lastname;
    }

    public String getEmail() {
        return email;
    }

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

    public Boolean getEnabled() {
        return enabled;
    }

    public void setEnabled(Boolean enabled) {
        this.enabled = enabled;
    }

    public List<Authority> getAuthorities() {
        return authorities;
    }

    public void setAuthorities(List<Authority> authorities) {
        this.authorities = authorities;
    }

    public Date getLastPasswordResetDate() {
        return lastPasswordResetDate;
    }

    public void setLastPasswordResetDate(Date lastPasswordResetDate) {
        this.lastPasswordResetDate = lastPasswordResetDate;
    }

    @ManyToMany(cascade = {CascadeType.PERSIST, CascadeType.MERGE})
    @JoinTable(name = "user_movie",
        joinColumns = @JoinColumn(name = "user_id", referencedColumnName = "id"),
        inverseJoinColumns = @JoinColumn(name = "movie_id", referencedColumnName = "id")
    )
    private Set<Movie> movies = new HashSet<>();

    public void addMovie(Movie movie) {
        movies.add(movie);
        movie.getUsers().add(this);
    }

    public void removeMovie(Movie movie) {
        movies.remove(movie);
        movie.getUsers().remove(this);
    }

}