新建项目

在application.properties配置文件中进行配置（或者application.yaml中配置也行）

spring.datasource.url=jdbc:mysql://localhost:3306/ssm?characterEncoding=utf8&useSSL=false&serverTimezone=UTC

spring.datasource.username=root

spring.datasource.password=root

#是否打印sql

spring.jpa.show-sql=true

#请求访问的时候加个路径前缀

server.servlet.context-path = /SpringBoot

实体类

一般在类名上写@Entity、@Table注解，以及主键上写@Id注解

//这里写Entity注解与Table注解

@Entity

@Table(name = "account")

public class Account {

//对主键写ID注解，GeneratedValue为自动递增注解

@Id

@GeneratedValue(strategy = GenerationType.IDENTITY)

private int id;

private String loginName;

private String password;

private String nickName;

private int age;

private String location;

public int getId() {

return id;

}

public void setId(int id) {

this.id = id;

}

public String getLoginName() {

return loginName;

}

public void setLoginName(String loginName) {

this.loginName = loginName;

}

public String getPassword() {

return password;

}

public void setPassword(String password) {

this.password = password;

}

public String getNickName() {

return nickName;

}

public void setNickName(String nickName) {

this.nickName = nickName;

}

public int getAge() {

return age;

}

public void setAge(int age) {

this.age = age;

}

public String getLocation() {

return location;

}

public void setLocation(String location) {

this.location = location;

}

}

DAO层

DAO层只要定义接口，并且继承JpaRepository接口就拥有基本的CRUD方法，同时可以写一些自己的特殊方法

public interface AccountDao extends JpaRepository<Account, Integer> {

List<Account> findByIdBetween(int i, int j);

Account findByLoginNameAndPassword(String loginName, String password);

@Query(" select a from Account a where a.id=?1 ")

List<Account> findByParam(Integer id);

}

Service 层

@Service

public class AccountService {

@Autowired

AccountDao accountDao;

public void save(Account account) {

accountDao.save(account);

}

public List<Account> list() {

return accountDao.findAll();

}

public List<Account> findByIdBetween(int min, int max) {

return accountDao.findByIdBetween(min, max);

}

public Account findByLoginNameAndPassword(String loginName, String password) {

return accountDao.findByLoginNameAndPassword(loginName, password);

}

public List<Account> findByParam(Integer id) {

return accountDao.findByParam(id);

}

}