整合DRUID数据源
实际的开发中，我们很少用上面那种方式的数据源。
引入DruidDataSource：
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.1.8</version>
</dependency>
配置：
type: com.alibaba.druid.pool.DruidDataSource
# 一些没整明白的基本配置，连接池啥的，慢慢整
initialSize: 5
minIdle: 5
maxActive: 20
maxWait: 60000
timeBetweenEvictionRunsMillis: 60000
minEvictableIdleTimeMillis: 300000
validationQuery: SELECT 1 FROM DUAL
testWhileIdle: true
testOnBorrow: false
testOnReturn: false
poolPreparedStatements: true
# 配置监控统计拦截的filters，去掉后监控界面sql无法统计，'wall'用于防火墙
filters: stat,wall,log4j
maxPoolPreparedStatementPerConnectionSize: 20
useGlobalDataSourceStat: true
connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500
基本配置的这些属性是和DataSourceProperties对应的，但这里配置了还不能够用到，还需要一个Configuration，目的是不使用反射的自动创建，自己创建并绑定属性。
@Configuration
public class DruidConfig {
@ConfigurationProperties(prefix = "spring.datasource")
@Bean
public DataSource druid() {
return new DruidDataSource();
}
//配置Druid的监控
//1、配置一个管理后台的Servlet
@Bean
public ServletRegistrationBean statViewServlet() {
ServletRegistrationBean bean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*");
//初始化参数
Map<String, String> initParams = new HashMap<>();
initParams.put("loginUsername", "root");
initParams.put("loginPassword", "root");
initParams.put("allow", "");//允许所有
initParams.put("deny", "36.1.52.144");//拒绝
bean.setInitParameters(initParams);
return bean;
}
//2、配置一个web监控的filter
@Bean
public FilterRegistrationBean webStatFilter() {
FilterRegistrationBean bean = new FilterRegistrationBean();
bean.setFilter(new WebStatFilter());
Map<String, String> initParams = new HashMap<>();
initParams.put("exclusions", "*.js,*.css,/druid/*");
bean.setInitParameters(initParams);
bean.setUrlPatterns(Arrays.asList("/*"));
return bean;
}
}
整合MyBatis
引入：
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.2</version>
</dependency>
创建数据库
创建Java Bean
使用MyBatis进行数据操作
使用注解版的使用：
创建mapper
/**
* @Mapper 指定这是一个操作数据库的mapper
*/
@Mapper
public interface DepartmentMapper {
@Select("select * from department where id=#{id}")
public Department getDeptById(Integer id);
@Delete("delete from department where id=#{id}")
public int deleteDeptById(Integer id);
@Options(useGeneratedKeys = true, keyProperty = "id")
@Insert("insert into department(departmentName) values(#{departmentName})")
public int insertDept(Department department);
@Update("update department set departmentName=#{departmentName} where id=#{id}")
public int updateDept(Department department);
创建Controller
@RestController
public class DeptController {
@Autowired
DepartmentMapper departmentMapper;
@GetMapping("/dept/{id}")
public Department getDept(@PathVariable("id") Integer id) {
return departmentMapper.getDeptById(id);
}
@GetMapping("/dept")
public Department insert(Department department) {
departmentMapper.insertDept(department);
return department;
}
}
目前，我们的数据库中表的字段名称和javaBean中属性名是一致的，如果改动了，则不能够匹配，者就需要一个配置文件或者配置类来解决这个问题。
创建MyBatisConfig类，使用自定义MyBatis的配置规则
@org.springframework.context.annotation.Configuration
public class MyBatisConfig {
@Bean
public ConfigurationCustomizer configurationCustomizer(){
return new ConfigurationCustomizer() {
@Override
public void customize(Configuration configuration) {
configuration.setMapUnderscoreToCamelCase(true);
}
};
}
}
可以使用 @MapperScan批量扫描。
配置文件的方式
EmployeeMapper.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.atguigu.springboot.mapper.EmployeeMapper">
<select id="getEmpById" resultType="com.atguigu.springboot.bean.Employee">
SELECT * FROM employee WHERE id=#{id}
</select>
<insert id="insertEmp">
INSERT INTO employee(lastName,email,gender,d_id) VALUES (#{lastName},#{email},#{gender},#{dId})
</insert>
</mapper>
mybatis.config.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<settings>
<!-- 与上文中一样，解决数据库中是aa_bc形式,javaBean中是aaBc形式查询字段匹配问题-->
<setting name="mapUnderscoreToCamelCase" value="true"/>
</settings>
</configuration>
当然还是需要mapper的
@Mapper
public interface EmployeeMapper {
public Employee getEmpById(Integer id);
public void insertEmp(Employee employee);
}
重要的一点，需要在yml文件中配置
mybatis:
mapper-locations: classpath:mybatis/mapper/*.xml 指定映射文件配置位置
config-location: classpath:mybatis/mybatis-config.xml 指定全局文件配置
运行测试的过程中，又出现了之前的异常
java.sql.SQLException: The server time zone value 'Öйú±ê׼ʱ¼ä' is unrecognized or represents more than one time
这次换用另一种方式解决，不使用命令 set global time_zone='+8:00' ;来解决，而是在数据库驱动url后面添加serverTimezone=UTC，也能解决这个问题。
url: jdbc:mysql://36.1.52.145:3306/jdbc?serverTimezone=UTC
