Java 调用init方法失败；嵌套异常为org.hibernate.AnnotationException：未为实体指定标识符

我刚开始学春天。当我试图在Spring in Action book中编写taco cloud应用程序时，我遇到了“未为实体指定标识符”错误。在第三章中，我尝试使用H2数据库学习JPA

我的订购型号：

package com.example.tacocloud.models;

import lombok.Data;

import javax.persistence.*;
import javax.validation.constraints.NotBlank;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

@Data
@Entity
@Table(name = "Taco_Order")
public class Order implements Serializable {

    ...

    @Id
    @GeneratedValue(strategy= GenerationType.AUTO)
    private Long id;
    private Date placedAt;

    @ManyToMany(targetEntity=Taco.class)
    private List<Taco> tacos = new ArrayList<>();

    public void addDesign(Taco design) {
        this.tacos.add(design);
    }

    @PrePersist
    void placedAt() {
        this.placedAt = new Date();
    }

}

还有我的墨西哥玉米卷课：

package com.example.tacocloud.models;

import lombok.Data;

import javax.persistence.*;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;
import java.util.Date;
import java.util.List;

@Data
@Entity
public class Taco {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;
    private Date createdAt;

    @NotNull
    @Size(min=5, message="Name must be at least 5 characters long")
    private  String name;
    @ManyToMany(targetEntity=Ingredient.class)
    @Size(min=1, message="You must choose at least 1 ingredient")
    private List<String> ingredients;

    @PrePersist
    void createdAt() {
        this.createdAt = new Date();
    }
}

schema.sql：

create table if not exists Ingredient (
  id varchar(4) not null,
  name varchar(25) not null,
  type varchar(10) not null
);
create table if not exists Taco (
  id identity,
  name varchar(50) not null,
  createdAt timestamp not null
);
create table if not exists Taco_Ingredients (
  taco bigint not null,
  ingredient varchar(4) not null
);
alter table Taco_Ingredients
    add foreign key (taco) references Taco(id);
alter table Taco_Ingredients
    add foreign key (ingredient) references Ingredient(id);
create table if not exists Taco_Order (
  id identity,
    deliveryName varchar(50) not null,
    deliveryStreet varchar(50) not null,
    deliveryCity varchar(50) not null,
    deliveryState varchar(2) not null,
    deliveryZip varchar(10) not null,
    ccNumber varchar(16) not null,
    ccExpiration varchar(5) not null,
    ccCVV varchar(3) not null,
    placedAt timestamp not null
);
create table if not exists Taco_Order_Tacos (
  tacoOrder bigint not null,
  taco bigint not null
);
alter table Taco_Order_Tacos
    add foreign key (tacoOrder) references Taco_Order(id);
alter table Taco_Order_Tacos
    add foreign key (taco) references Taco(id);

顺便说一句，my application.properties：

spring.datasource.url=jdbc:h2:mem:testdb
spring.datasource.driver-class-name = org.h2.Driver
spring.datasource.username=sa
spring.datasource.password=
spring.jpa.database-platform=org.hibernate.dialect.H2Dialect

---

谢谢。

您的类

成分

没有

@Id

字段，而且它是一个不可变对象类，不适合序列化类-您必须像其他所有类一样拥有默认构造函数。删除

@noargsconstuctor（access=AccessLevel.PRIVATE，force=true）

这非常奇怪，可能会混淆您的框架

您的类

成分

没有

@Id

字段，而且它是一个不可变对象类，不适合序列化类-您必须像其他类一样拥有默认构造函数。删除

@noargsconstuctor（access=AccessLevel.PRIVATE，force=true）

这很奇怪，可能会混淆您的框架

create table if not exists Ingredient (
  id varchar(4) not null,
  name varchar(25) not null,
  type varchar(10) not null
);
create table if not exists Taco (
  id identity,
  name varchar(50) not null,
  createdAt timestamp not null
);
create table if not exists Taco_Ingredients (
  taco bigint not null,
  ingredient varchar(4) not null
);
alter table Taco_Ingredients
    add foreign key (taco) references Taco(id);
alter table Taco_Ingredients
    add foreign key (ingredient) references Ingredient(id);
create table if not exists Taco_Order (
  id identity,
    deliveryName varchar(50) not null,
    deliveryStreet varchar(50) not null,
    deliveryCity varchar(50) not null,
    deliveryState varchar(2) not null,
    deliveryZip varchar(10) not null,
    ccNumber varchar(16) not null,
    ccExpiration varchar(5) not null,
    ccCVV varchar(3) not null,
    placedAt timestamp not null
);
create table if not exists Taco_Order_Tacos (
  tacoOrder bigint not null,
  taco bigint not null
);
alter table Taco_Order_Tacos
    add foreign key (tacoOrder) references Taco_Order(id);
alter table Taco_Order_Tacos
    add foreign key (taco) references Taco(id);

spring.datasource.url=jdbc:h2:mem:testdb
spring.datasource.driver-class-name = org.h2.Driver
spring.datasource.username=sa
spring.datasource.password=
spring.jpa.database-platform=org.hibernate.dialect.H2Dialect