java - 没有本地生成的身份值

Question

我是 springframework 技术的新手，我正在努力解决以下错误。项目启动成功，执行 postman 时出现以下错误谁能帮我解决这个问题。我想我已经粘贴了重要的类，如果需要我可以发布整个代码

用户 Controller

package com.appsdeveloper.blog.app.ws.controller;

import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.DeleteMapping;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.PutMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import com.appsdeveloper.blog.app.ws.service.UserService;
import com.appsdeveloper.blog.app.ws.shared.dto.UserDto;
import com.appsdeveloper.blog.app.ws.ui.model.request.UserDetailsRequestModel;
import com.appsdeveloper.blog.app.ws.ui.model.response.UserRest;

@RestController
@RequestMapping("users")//http://localhost:8586/users

public class UserController{

    @Autowired(required=true)//the bracket added from the internet
    UserService userService;

    //@Autowired
    //private UserRepository userRepository;

    @PostMapping
    public UserRest createUser(@RequestBody UserDetailsRequestModel userDetails){

        UserRest returnValue = new UserRest();

        UserDto userDto = new UserDto();
        BeanUtils.copyProperties(userDetails, userDto);

        UserDto createdUser = userService.createUser(userDto);
        BeanUtils.copyProperties(createdUser, returnValue);

        return returnValue;
    }

    @DeleteMapping
    public String deleteUser(){
        return "delete user was called";
    }

    @GetMapping
    public  String getUser(){
        return "get User was called";
    }

    @PutMapping
    public String updateUser(){
        return "update user was called";
    }
}

用户实体

package com.appsdeveloper.blog.app.ws.io.entity;

import java.io.Serializable;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name="users", schema = "photo_app" )//name of table created to store information
public class UserEntity implements Serializable {

    private static final long serialVersionUID = 7401188933477397731L;

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

    @Column(name= "userId", nullable = false)
    private String userId;

    @Column(name = "firstName", nullable = false, length = 50)//the length is important to avoid default size 0f 250 varchar
    private String firstName;

    @Column(name = "lastName", nullable = false, length = 50)
    private String lastname;

    @Column(name = "email", length = 50)
    private String email;

    @Column(name = "password", nullable = false)
    private String encryptedPassword;

    //@Column(name = "emailVerificationToken", nullable = false)
    private String emailVerificationToken;


    @Column(name = "emailVerificationStatus", nullable=false)
    private Boolean emailVerificationStatus = false;


    public long getId() {
        return id;
    }
    public String getUserId() {
        return userId;
    }
    public String getFirstName() {
        return firstName;
    }
    public String getLastname() {
        return lastname;
    }
    public String getEmail() {
        return email;
    }
    public String getEncryptedPassword() {
        return encryptedPassword;
    }
    public String getEmailVerificationToken() {
        return emailVerificationToken;
    }

    public Boolean getEmailVerificationStatus() {
    return emailVerificationStatus;
    }



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

    public void setUserId(String userId) {
        this.userId = userId;
    }
    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }
    public void setLastname(String lastname) {
        this.lastname = lastname;
    }

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

    public void setEncryptedPassword(String encryptedPassword) {
        this.encryptedPassword = encryptedPassword;
    }

    public void setEmailVerificationToken(String emailVerificationToken) {
        this.emailVerificationToken = emailVerificationToken;
    }

    public void setEmailVerificationStatus(boolean emailVerificationStatus) {
        this.emailVerificationStatus = emailVerificationStatus;
    }

}

应用程序属性

spring.datasource.username=root
spring.datasource.password=
spring.datasource.url=jdbc:mysql://localhost:3306/photo_app
server.port=8586
spring.jpa.hibernate.use-new-id-generator-mappings=false

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.1.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.appsdeveloperblog-app-ws</groupId>
    <artifactId>mobile-app-ws</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>mobile-app-ws</name>
    <description>Demo project for Spring Boot</description>

    <properties><!--</tiles:insertDefinition>-->
    <!-- <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>-->
        <java.version>1.8</java.version>
        <property name="hibernate.hbm2ddl.auto" value="create-drop" />  
    </properties>



    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>


        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>


        <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
        <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                 <version>8.0.19</version> 
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-core -->
        <dependency>
            <groupId>org.hibernate</groupId>
             <artifactId>hibernate-core</artifactId>
            <version>6.0.0.Alpha4</version>
             <type>pom</type>
        </dependency>

        <!-- https://mvnrepository.com/artifact/joda-time/joda-time -->
        <dependency>
            <groupId>joda-time</groupId>
            <artifactId>joda-time</artifactId>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.jadira.usertype/usertype.core -->
        <dependency>
            <groupId>org.jadira.usertype</groupId>
            <artifactId>usertype.core</artifactId>
            <version>7.0.0.CR1</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

错误代码

Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.orm.jpa.JpaSystemException: The database returned no natively generated identity value; nested exception is org.hibernate.HibernateException: The database returned no natively generated identity value] with root cause

org.hibernate.HibernateException: The database returned no natively generated identity value

Answer 1

您必须自动递增数据库中的id列。

类似这样的:id INT NOT NULL AUTO_INCRMENT