java - 未使用 App Engine Java 在 JPA 中生成主键

Question

我有实体类“User”，如下所示，但它不生成主键。我在我的应用程序引擎应用程序中使用 JPA 并在我的 Android 客户端中使用应用程序引擎端点。

实体类:

@Entity
public class UserMaster {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long userId;

    private String userName;
    private String fullName;
    private String userAvtarUrl;
    private String userAbout;
    private String userGender;


    public String getUserName() {
        return userName;
    }

    public Long getUserId() {
        return userId;
    }

    public void setUserId(Long userId) {
        this.userId = userId;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getFullName() {
        return fullName;
    }

    public void setFullName(String fullName) {
        this.fullName = fullName;
    }

    public String getUserAvtarUrl() {
        return userAvtarUrl;
    }

    public void setUserAvtarUrl(String userAvtarUrl) {
        this.userAvtarUrl = userAvtarUrl;
    }

    public String getUserAbout() {
        return userAbout;
    }

    public void setUserAbout(String userAbout) {
        this.userAbout = userAbout;
    }

    public String getUserGender() {
        return userGender;
    }

    public void setUserGender(String userGender) {
        this.userGender = userGender;
    }
}

端点持久化代码:

@ApiMethod(name = "insertUserMaster")
    public UserMaster insertUserMaster(UserMaster usermaster) {
        EntityManager mgr = getEntityManager();
        try {
            if (containsUserMaster(usermaster)) {
                throw new EntityExistsException("Object already exists");
            }
            mgr.persist(usermaster);
        } finally {
            mgr.close();
        }
        return usermaster;
    }

Android客户端

Userendpoint.Builder builder = new Userendpoint.Builder(
                        AndroidHttp.newCompatibleTransport(),
                        new JacksonFactory(), new HttpRequestInitializer() {
                            public void initialize(HttpRequest httpRequest) {
                            }
                        });

                Userendpoint endpoint = CloudEndpointUtils.updateBuilder(
                        builder).build();

                User objUser = new User();

                objUser.setUserName(txtName.getText().toString());
                objUser.setUserEmail(txtEmail.getText().toString());

                Bitmap bmp = BitmapFactory.decodeFile(imagePath);
                ByteArrayOutputStream out = new ByteArrayOutputStream();
                bmp.compress(Bitmap.CompressFormat.PNG, 100, out);
                byte[] imgByte = out.toByteArray();
                String encodedImage = Base64.encodeToString(imgByte,
                        Base64.DEFAULT);
                objUser.setImage(encodedImage);

                User result = endpoint.insertUser(objUser).execute();

请指导我哪里不足。谢谢。

Answer 1

如果使用 JPA 和 GAE/数据存储，请使用所有 JPA 注释，或者全部作为供应商扩展使用所有 JDO 注释。您不能混合搭配。