目录
整合jdbc
1. 新建项目
2. 编写yaml配置文件连接数据库
spring:
datasource:
username: root
password: root
url: jdbc:mysql://localhost:3306/springboot?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8
driver-class-name: com.mysql.cj.jdbc.Driver
3. 测试类
@SpringBootTest
class Springboot04JdbcApplicationTests {
@Autowired
DataSource dataSource;//注入依赖
@Test
void contextLoads() throws SQLException {
System.out.println(dataSource.getClass());//测试一下类型
Connection connection = dataSource.getConnection();
System.out.println(connection);
}
}可以得到数据源为：class com.zaxxer.hikari.HikariDataSource
使用原生的jdbcTemplate进行访问测试
-
execute方法：可以用于执行任何SQL语句，一般用于执行DDL语句；
-
update方法及batchUpdate方法：update方法用于执行新增、修改、删除等语句；batchUpdate方法用于执行批处理相关语句；
-
query方法及queryForXXX方法：用于执行查询相关语句；
-
call方法：用于执行存储过程、函数相关语句。
@RestController
public class JDBCController {
@Autowired
JdbcTemplate jdbcTemplate;
@RequestMapping(value = "/list")
public List<Map<String,Object>> userList(){
String sql = "select * from user";
List<Map<String, Object>> list = jdbcTemplate.queryForList(sql);
return list;
}
}使用Druid连接池
1. 添加类型
在yml中设置type
type: com.alibaba.druid.pool.DruidDataSource # 自定义数据源
2. 初始化连接池
initialSize: 5
minIdle: 5
maxActive: 20
maxWait: 60000
timeBetweenEvictionRunsMillis: 60000
minEvictableIdleTimeMillis: 300000
validationQuery: SELECT 1 FROM DUAL
testWhileIdle: true
testOnBorrow: false
testOnReturn: false
poolPreparedStatements: true3. 编写config类
@Configuration
public class DruidConfig {
@ConfigurationProperties(prefix = "spring.datasource")
@Bean
public DataSource druidDataSource(){
return new DruidDataSource();
}
}@ConfigurationProperties(prefix = "spring.datasource")：
将全局配置文件中前缀为 spring.datasource的属性值注入到 com.alibaba.druid.pool.DruidDataSource 的同名参数中
配置Druid数据源监视
@Bean
public ServletRegistrationBean servletRegistrationBean(){
ServletRegistrationBean bean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*");
HashMap<String, String> init = new HashMap<>();
init.put("loginUsername","admin");//初始化
init.put("loginPassword","123");
//后台允许谁访问
init.put("allow","");
bean.setInitParameters(init);
return bean;
}当执行一次sql时，后台会有监视
整合Mybatis
1. 导入依赖
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.1.1</version>
</dependency>2. 编写mapper接口
@Mapper
@Component
public interface UserMapper {
List<User> query();
}@Mapper : 表示本类是一个 MyBatis 的 Mapper
3. 编写实体类
使用Lombok注解
@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {
int id;
String name;
String password;
}4. 编写mapper.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.demos.mapper.UserMapper">
<select id="query" resultType="User">
select * from user
</select>
</mapper>5. controller层调用方法
@RestController
public class UserController {
@Autowired
UserMapper userMapper;
@RequestMapping(value = "/query")
public List query(){
List<User> query = userMapper.query();
return query;
}
}