springboot集成Druid与Mybatis

集成Druid

1.1Java程序很大的一部分都是要操作数据库的，为了提高操作数据库的性能，所以一般会使用连接池！ Druid 是阿里巴巴的开源组件之一，结合了C3P0，DBCP的优点，并且自带日志监控！ Druid 可以天然的监控 SQL 和 数据库连接池的状况！

要使用第三方数据源
1、导入依赖
2、看源码配置
3、看官方解释
4、测试使用！
1、导入依赖

        
            com.alibaba
            druid
            1.0.9
        
        
            log4j
            log4j
            1.2.17
        

2、看源码配置

spring:
 datasource:
   username: root
   password: root
# 注意8.0以上需要时区的配置
   url: jdbc:mysql://localhost:3306/springboot?useSSL=false
   driverClassName: com.mysql.jdbc.Driver
   type:  com.alibaba.druid.pool.DruidDataSource

#Spring Boot 默认是不注入这些属性值的，需要自己绑定
#druid 数据源专有配置
   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，stat:监控统计、log4j：日志记录、wall：防御sql注入
#如果允许时报错	java.lang.ClassNotFoundException: org.apache.log4j.Priority #则导入 log4j 依赖即可，Maven 地址：
#https://mvnrepository.com/artifact/log4j/log4j
   filters: stat,wall,log4j
   maxPoolPreparedStatementPerConnectionSize: 20
   useGlobalDataSourceStat: true
   connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500

3.Druid参数不会自动生效需要自己手动配置

@Configuration
public class DruidConfig {
    @ConfigurationProperties("spring.datasource")
    @Bean
    public DataSource druidDataSource(){
        return new DruidDataSource();
    }
    // 注册后台监控页面。SpringBoot 如何注册Servlet    
    // 没有web.xml 的情况配置 Servlet 的方法  ： ServletRegistrationBean    
    // 测试访问 /drui
    @Bean
    public ServletRegistrationBean statViewServlet(){
        //StatViewServlet   配置后台监控
        ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(new StatViewServlet(),"/druid/*");
        HashMapmap = new HashMap<>();
        //后台登陆
        map.put("loginUsername","admin");
        map.put("loginPassword","123456");
        //访问权
       //只允许本地访问
       // map.put("allow","localhost");
        map.put("allow","");//允许所有人

       // map.put("deny","196.168.1.1"); 拒绝ip...访问
        servletRegistrationBean.setInitParameters(map);
        return servletRegistrationBean;
    }
    //过滤器的配置
    //没有web.xml 的情况配置 Filter 的方法！ FilterRegistrationBean
    @Bean
    public FilterRegistrationBean webStatFilter(){
        FilterRegistrationBean bean = new FilterRegistrationBean();
        bean.setFilter(new WebStatFilter());
       // 配置内容        
        // 配置哪些请求可以被过滤
        HashMapmap = new HashMap<>();
        map.put("exclusions","*.js,*.css,/druid/*");
        bean.setInitParameters(map);

        bean.setUrlPatterns(Arrays.asList("/*"));
        return bean;
    }
}

测试
在SpringBoot未来的集成中
1、导入pom依赖
2、编写一些配置
3、编写Config
SpringCloud 套路
1、导入pom配置文件
2、编写一些配置
3、开启一个注解！

集成Mybatis

MyBatis：https://mybatis.org/mybatis-3/getting-started.html
MyBatis-Spring：http://mybatis.org/spring/zh/factorybean.html
MyBatis Spring Boot Starter：http://mybatis.org/spring-boot-starter/mybatis-spring-boot-autocon figure/
1、导入pom依赖

       
            org.mybatis.spring.boot
            mybatis-spring-boot-starter
            2.1.2
        

2、编写一些配置

debug=false
spring.datasource.driverClassName=com.mysql.jdbc.Driver
# 注意8.0以上需要时区的配置
# url: jdbc:mysql://localhost:3306/springboot? serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8
spring.datasource.url=jdbc:mysql://localhost:3306/springboot?useSSL=false
spring.datasource.username=root
spring.datasource.password=root
#mybatis-plus.configuration.logimpl=org.apache.ibatis.logging.stdout.StdOutImpl
#mybatis-plus.global-config.db-config.logic-delete-value=1
#mybatis-plus.global-config.db-config.logic-not-delete-value=0
spring.profiles.active=dev
# 配置mybatis的配置
mybatis.configuration.map-underscore-to-camel-case=true
mybatis.type-aliases-package=com.shying.pojo
# mybatis.config-location=
mybatis.mapper-locations=classpath:com/shying/mapper/xml/*.xml

3、测试是否连接成功

@SpringBootTest
class ShyingMybatisApplicationTests {
    @Autowired
    DataSource dataSource;
    @Test
    void contextLoads() throws SQLException {
        System.out.println(dataSource.getClass());
        Connection connection = dataSource.getConnection();
        System.out.println(connection);
        DruidDataSource druidDataSource = (DruidDataSource)this.dataSource;
        System.out.println(druidDataSource.getActiveCount());
        System.out.println(druidDataSource.getActivePeak());
        System.out.println(druidDataSource.getMaxActive());
        System.out.println(druidDataSource.getMinIdle());
        connection.close();
    }

}

4、编写实体类

@Data
@AllArgsConstructor
@NoArgsConstructor
public class Department {
private int id;
    private String departmentName;
}

5、编写Mapper.xml

    
    select * from department
  

6.配置maven资源过滤

      
            
            
                src/main/java
                
                    **/*.properties
                    **/*.xml
                
                false
            
            
                src/main/resources
                
                    **/*.*
                
                false
            
        

7.测试

@RestController
public class DepartmentController {
    @Autowired
    DepartmentMapper departmentMapper;
    @RequestMapping("/select")
    public List selectAll(){
        List departments = departmentMapper.selectAll();
        return departments;
    }
}