連接數(shù)據(jù)庫的方式有很多，比如Jpa（參考SpringBoot整合JPA），Mybatis（參考SpringBoot整合Mybatis），原生JDBC等，本文主要詳細講述借助JdbcTemplate來操作數(shù)據(jù)庫
首先新建一個web工程，打開pom.xml引入相關(guān)依賴

        <!--JDBC依賴-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <!--mysql依賴-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

配置數(shù)據(jù)庫連接

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/test_jdbc?serverTimezone=UTC
    username: root
    password: root
    driver-class-name: com.mysql.jdbc.Driver

新建表tb_user，添加一條數(shù)據(jù)

新建實體類User

public class User {
    private Integer id;

    private String lastName;

    private String email;

    public Integer getId() {
        return id;
    }

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

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getEmail() {
        return email;
    }

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

實現(xiàn)dao層，新建UserDao

@Repository
public class UserDao {

    @Autowired
    JdbcTemplate jdbcTemplate;

    public List<Map<String, Object>> selectUser() {
        List<Map<String, Object>> list = jdbcTemplate.queryForList("select * from tb2_user");
        if (list.size() > 0) {
            return list;
        }
        return null;
    }

}

為了簡單就省略service層，直接新建UserController

@RestController
public class Usercontroller {

    @Autowired
    UserDao userDao;

    @GetMapping("/user")
    public List<Map<String, Object>> insertUser() {
        List<Map<String, Object>> list = userDao.selectUser();
        return list;
    }
}

啟動項目，瀏覽器輸入localhost:8080/user，得到數(shù)據(jù)，整合成功