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文章目录

• SpringBootJpa简单操作Mysql数据库
• • pom文件依赖
  • properties文件配置
  • User实体类
  • UserRepository类,继承JpaRepository类，具有简单的操作数据库函数
  • 创建UserCOntroller，并注入UserRepository

SpringBootJpa简单操作Mysql数据库

pom文件依赖

    <properties>
        <java.version>1.8</java.version>
    </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>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

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

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

</project>

properties文件配置

spring.datasource.url=jdbc:mysql://localhost:3306/test?characterEncoding=utf8&useSSL=false&serverTimezone=Asia/Shanghai
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

##JPA配置
## validate 加载hibernate时，验证创建数据表结构
## create 每次加载hibernate，重新创建数据表结构，这会导致数据表数据丢失
## create-drop 加载hibernate时创建，退出时删除表结构
## update  加载hibernate自动更新数据库结构
## none   启动时不做任何操作
spring.jpa.hibernate.ddl-auto=create
## 控制台打印
spring.jpa.show-sql=true

User实体类

@Entity
public class User {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    @Column(nullable = false, unique = true)
    private String user_name;
    @Column
    private String user_password;

    public User(Long id, String user_name, String user_password){
        this.id = id;
        this.user_name = user_name;
        this.user_password = user_password;
    }

    public User(String user_name, String user_password){
        this.user_name = user_name;
        this.user_password = user_password;
    }

    public User(){

    };

    public Long getId() {
        return id;
    }

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

    public String getUser_name() {
        return user_name;
    }

    public void setUser_name(String user_name) {
        this.user_name = user_name;
    }

    public String getUser_password() {
        return user_password;
    }

    public void setUser_password(String user_password) {
        this.user_password = user_password;
    }
}

UserRepository类,继承JpaRepository类，具有简单的操作数据库函数

public interface UserRepository extends JpaRepository<User, Long> {

}

创建UserCOntroller，并注入UserRepository

@RestController
@RequestMapping("test")
public class UserController {

    @Autowired
    private UserRepository userRepository;

    @GetMapping("/saveUser")
    public void saveUser(String userName, String userPassword){
        User user = new User(userName, userPassword);
        userRepository.save(user);
    }

    @GetMapping("/updateUser")
    public void updateUser(Long id, String userName, String userPassword){
        User user = new User(id, userName, userPassword);
        userRepository.save(user);
    }

    @GetMapping("/deleteUser")
    public void deleteUser(Long id){
        userRepository.deleteById(id);
    }

    @GetMapping("/getUserById")
    public Optional<User> getUserById(Long id){
        return userRepository.findById(id);
    }
}