本文以druid数据库连接池及mybatis框架,搭建基本的应用开发框架。
1、druid数据库连接池
1.1、Druid是什么?有什么作用?
Druid首先是一个数据库连接池,但它不仅仅是一个数据库连接池,它还包含一个ProxyDriver,一系列内置的JDBC组件库,一个SQL Parser。
整个项目由数据库连接池、插件框架和SQL解析器组成。该项目主要是为了扩展JDBC的一些限制,可以让程序员实现一些特殊的需求,比如向密钥服务请求凭证、统计SQL信息、SQL性能收集、SQL注入检查、SQL翻译等,程序员可以通过定制来实现自己需要的功能。
github:https://github.com/alibaba/druid
1.2、Druid支持哪些数据库?
Druid支持所有JDBC兼容的数据库,包括Oracle、MySql、Derby、Postgresql、SQL Server、H2等等。
Druid针对Oracle和MySql做了特别优化,比如Oracle的PS Cache内存占用优化,MySql的ping检测优化。
1.3、Druid是如何扩展JDBC的?
Druid在DruidDataSourc和ProxyDriver上提供了Filter-Chain模式的扩展API,类似Serlvet的Filter,配置Filter拦截JDBC的方法调用。
1.4、Druid有那些监控特性?
- 监控SQL的执行时间、ResultSet持有时间、返回行数、更新行数、错误次数、错误堆栈信息。
- SQL执行的耗时区间分布。什么是耗时区间分布呢?比如说,某个SQL执行了1000次,其中01毫秒区间50次,110毫秒800次,10100毫秒100次,1001000毫秒30次,1~10秒15次,10秒以上5次。通过耗时区间分布,能够非常清楚知道SQL的执行耗时情况。
- 监控连接池的物理连接创建和销毁次数、逻辑连接的申请和关闭次数、非空等待次数、PSCache命中率等。
2、配置druid数据库连接池
目前Spring Boot中默认支持的连接池有dbcp,dbcp2, tomcat, hikari三种连接池,若要支持druid,需要我们自己配置;
2.1、基于java代码配置
2.1.1、pom依赖
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.0.25</version>
</dependency>
2.1.2、application.properties配置信息
# 驱动配置信息
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
spring.datasource.driverClassName = com.mysql.jdbc.Driver
spring.datasource.url = jdbc:mysql://192.168.101.xx:3306/jdronetest?characterEncoding=UTF-8
spring.datasource.username = xxxxx
spring.datasource.password = xxxxxxx
#连接池的配置信息
spring.datasource.initialSize=2
spring.datasource.minIdle=2
spring.datasource.maxActive=2
spring.datasource.maxWait=60000
spring.datasource.timeBetweenEvictionRunsMillis=60000
spring.datasource.minEvictableIdleTimeMillis=300000
spring.datasource.validationQuery=SELECT 1 FROM USER
spring.datasource.testWhileIdle=true
spring.datasource.testOnBorrow=false
spring.datasource.testOnReturn=false
spring.datasource.poolPreparedStatements=true
spring.datasource.maxPoolPreparedStatementPerConnectionSize=20
spring.datasource.filters=stat,wall,log4j
spring.datasource.connectionProperties=druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
2.1.3、定义DataSource
package com.springboot.demo.config;
import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import javax.sql.DataSource;
import java.sql.SQLException;
@SuppressWarnings("all")
@Configuration
public class DruidConfig {
private static final Logger log = LoggerFactory.getLogger(DruidConfig.class);
@Value("${spring.datasource.url}")
private String dbUrl;
@Value("${spring.datasource.username}")
private String username;
@Value("${spring.datasource.password}")
private String password;
@Value("${spring.datasource.driverClassName}")
private String driverClassName;
@Value("${spring.datasource.initialSize}")
private int initialSize;
@Value("${spring.datasource.minIdle}")
private int minIdle;
@Value("${spring.datasource.maxActive}")
private int maxActive;
@Value("${spring.datasource.maxWait}")
private int maxWait;
@Value("${spring.datasource.timeBetweenEvictionRunsMillis}")
private int timeBetweenEvictionRunsMillis;
@Value("${spring.datasource.minEvictableIdleTimeMillis}")
private int minEvictableIdleTimeMillis;
@Value("${spring.datasource.validationQuery}")
private String validationQuery;
@Value("${spring.datasource.testWhileIdle}")
private boolean testWhileIdle;
@Value("${spring.datasource.testOnBorrow}")
private boolean testOnBorrow;
@Value("${spring.datasource.testOnReturn}")
private boolean testOnReturn;
@Value("${spring.datasource.poolPreparedStatements}")
private boolean poolPreparedStatements;
@Value("${spring.datasource.maxPoolPreparedStatementPerConnectionSize}")
private int maxPoolPreparedStatementPerConnectionSize;
@Value("${spring.datasource.filters}")
private String filters;
@Value("{spring.datasource.connectionProperties}")
private String connectionProperties;
@Bean(initMethod = "init", destroyMethod = "close")
@Primary
public DataSource dataSource() {
DruidDataSource datasource = new DruidDataSource();
datasource.setUrl(this.dbUrl);
datasource.setUsername(username);
datasource.setPassword(password);
datasource.setDriverClassName(driverClassName);
/** configuration */
datasource.setInitialSize(initialSize);
datasource.setMinIdle(minIdle);
datasource.setMaxActive(maxActive);
datasource.setMaxWait(maxWait);
datasource.setTimeBetweenEvictionRunsMillis(timeBetweenEvictionRunsMillis);
datasource.setMinEvictableIdleTimeMillis(minEvictableIdleTimeMillis);
datasource.setValidationQuery(validationQuery);
datasource.setTestWhileIdle(testWhileIdle);
datasource.setTestOnBorrow(testOnBorrow);
datasource.setTestOnReturn(testOnReturn);
datasource.setPoolPreparedStatements(poolPreparedStatements);
datasource.setMaxPoolPreparedStatementPerConnectionSize(maxPoolPreparedStatementPerConnectionSize);
try {
datasource.setFilters(filters);
} catch (SQLException e) {
log.error("druid configuration initialization filter", e);
}
datasource.setConnectionProperties(connectionProperties);
return datasource;
}
/**
* http://127.0.0.1:8090/monitor/druid/login.html
*
* @throws
* @Title: druidServlet
* @Description: 注册一个StatViewServlet 相当于在web.xml中声明了一个servlet
* @param: void
* @return: ServletRegistrationBean
*/
@Bean
public ServletRegistrationBean druidServlet() {
ServletRegistrationBean reg = new ServletRegistrationBean();
reg.setServlet(new StatViewServlet());
reg.addUrlMappings("/druid/*");
/** 白名单 */
// IP白名单
reg.addInitParameter("allow", "*");
// IP黑名单(共同存在时,deny优先于allow)
reg.addInitParameter("deny", "192.168.1.100");
/** /druid/login.html登录时账号密码 */
reg.addInitParameter("loginUsername", "zhaozhou");
reg.addInitParameter("loginPassword", "zhaozhou");
/** 是否能够重置数据 禁用HTML页面上的“Reset All”功能 */
reg.addInitParameter("resetEnable", "false");
return reg;
}
/**
* 注册一个:filterRegistrationBean 相当于在web.xml中声明了一个Filter
*/
@Bean
public FilterRegistrationBean druidStatFilter() {
FilterRegistrationBean druidStatFilter = new FilterRegistrationBean();
druidStatFilter.setFilter(new WebStatFilter());
/** 添加过滤规则. */
druidStatFilter.addUrlPatterns("/*");
/** 监控选项滤器 */
druidStatFilter.addInitParameter("DruidWebStatFilter", "/*");
/** 添加不需要忽略的格式信息. */
druidStatFilter.addInitParameter("exclusions",
"*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*");
/** 配置profileEnable能够监控单个url调用的sql列表 */
druidStatFilter.addInitParameter("profileEnable", "true");
/** 当前的cookie的用户 */
druidStatFilter.addInitParameter("principalCookieName", "USER_COOKIE");
/** 当前的session的用户 */
druidStatFilter
.addInitParameter("principalSessionName", "USER_SESSION");
return druidStatFilter;
}
}
2.2、基于starter配置
此种配置只需要配置pom及application.properties信息即可;
2.2.1、pom配置
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>1.1.8</version>
</dependency>
2.3、mybatis配置
2.3.1、pom配置
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.2</version>
</dependency>
2.3.2、application.properties配置
mybatis.mapper-locations=classpath:mapper/*.xml
mybatis.type-aliases-package=com.springboot.demo.entity
2.3.3、@MapperScan配置
@SpringBootApplication
@MapperScan("com.springboot.demo.dao")
public class TestApplication {
public static void main(String[] args) {
SpringApplication.run(TestApplication.class, args);
}
}
2.3.3、mabatis扩展配置
mybatis.config-location:指定mybatis-config.xml的位置;
mybatis.check-config-location:检查mybatis-config.xml是否存在;
mybatis.mapper-locations:指定mapper的xml的位置;
mybatis.type-aliases-package:指定别名的包,可以多个,逗号分隔;
mybatis.type-handlers-package:指定handler的扫描码路径;
mybatis.executor-type:执行器类型: SIMPLE, REUSE, BATCH;
mybatis.configuration-properties:MyBatis配置的外部化属性。指定的属性可以用作MyBatis配置文件和映射文件的占位符;
mybatis.configuration:嵌套配置,具体子配置如下;
defaultStatementTimeout:设置超时时间,它决定驱动等待数据库响应的秒数;
defaultFetchSize:为驱动的结果集获取数量(fetchSize)设置一个提示值。此参数只可以在查询设置中被覆盖;
mapUnderscoreToCamelCase:是否开启自动驼峰命名规则(camel case)映射,即从经典数据库列名 A_COLUMN 到经典 Java 属性名 aColumn 的类似映射;
autoMappingUnknownColumnBehavior:指定发现自动映射目标未知列(或者未知属性类型)的行为;NONE:不做任何反应;WARNING:输出提醒日志 ('org.apache.ibatis.session.AutoMappingUnknownColumnBehavior' 的日志等级必须设置为 WARN);FAILING:映射失败 (抛出 SqlSessionException);
具体参考:http://www.mybatis.org/spring-boot-starter/mybatis-spring-boot-autoconfigure/
2.3、日志配置
2.3.1、pom配置
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
2.3.2、application.properties配置
logging.level.root = debug
本处只做基本的root配置,可以看到sql的日志即可,不做过多配置;
3、项目最终结果
3.1、项目目录结构
目录结构.png3.2、dao层
package com.springboot.demo.dao;
import com.springboot.demo.entity.User;
public interface UserDao {
User getUserById(Long id);
}
dao层只提供一个接口,通过用户id查找用户信息;
3.3、entity数据库实体
/**
* @author
*/
public class User implements Serializable {
/**
* 主键id
*/
private Long id;
/**
* 用户名
*/
private String name;
/**
* 电话
*/
private String tel;
/**
* 邮件
*/
private String email;
/**
* 航线编号
*/
private Date createTime;
//getter、setter方法
}
3.4、mapper文件
<?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.springboot.demo.dao.UserDao">
<resultMap id="BaseResultMap" type="com.springboot.demo.entity.User">
<id column="id" jdbcType="BIGINT" property="id" />
<result column="name" jdbcType="VARCHAR" property="name" />
<result column="tel" jdbcType="VARCHAR" property="tel"/>
<result column="email" jdbcType="VARCHAR" property="email" />
<result column="create_time" jdbcType="TIMESTAMP" property="createTime" />
</resultMap>
<sql id="Base_Column_List">
id, name, tel, email, create_time
</sql>
<!-- 通过ID获取用户信息-->
<select id="getUserById" parameterType="Long" resultMap="BaseResultMap">
select
<include refid="Base_Column_List" />
from t_user
<where>
id = #{id, jdbcType=BIGINT}
</where>
</select>
</mapper>
3.5、test测试用例
@RunWith(SpringRunner.class)
@SpringBootTest
public class TestApplicationTests {
@Resource
private UserService userService;
@Test
public void getUserTest() {
User user = userService.getUserById(1L);
System.out.println("用户名:" + user.getName());
}
}
3.6、运行test结果
2018-10-30 14:57:14.552 DEBUG 9816 --- [ main] org.mybatis.spring.SqlSessionUtils : Creating a new SqlSession
2018-10-30 14:57:14.556 DEBUG 9816 --- [ main] org.mybatis.spring.SqlSessionUtils : SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@4f1fb828] was not registered for synchronization because synchronization is not active
2018-10-30 14:57:14.595 DEBUG 9816 --- [ main] o.s.jdbc.datasource.DataSourceUtils : Fetching JDBC Connection from DataSource
2018-10-30 14:57:14.599 DEBUG 9816 --- [ main] o.m.s.t.SpringManagedTransaction : JDBC Connection [com.alibaba.druid.proxy.jdbc.ConnectionProxyImpl@6a55594b] will not be managed by Spring
2018-10-30 14:57:14.603 DEBUG 9816 --- [ main] c.s.demo.dao.UserDao.getUserById : ==> Preparing: select id, name, tel, email, create_time from t_user WHERE id = ?
2018-10-30 14:57:14.769 DEBUG 9816 --- [ main] c.s.demo.dao.UserDao.getUserById : ==> Parameters: 1(Long)
2018-10-30 14:57:14.790 DEBUG 9816 --- [ main] c.s.demo.dao.UserDao.getUserById : <== Total: 1
2018-10-30 14:57:14.791 DEBUG 9816 --- [ main] c.a.druid.pool.PreparedStatementPool : {conn-10002, pstmt-20000} enter cache
2018-10-30 14:57:14.791 DEBUG 9816 --- [ main] org.mybatis.spring.SqlSessionUtils : Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@4f1fb828]
2018-10-30 14:57:14.791 DEBUG 9816 --- [ main] o.s.jdbc.datasource.DataSourceUtils : Returning JDBC Connection to DataSource
用户名:zhaozhou
以上为运行查询日志,可以看到,数据库事务及查询语句都运行正常。
示例源码:https://github.com/zhaozhou11/spring-boot-demo.git
相关阅读:
spring-boot基础环境搭建 【https://www.jianshu.com/p/ee36bb9faa10】
spring-boot配置详解【https://www.jianshu.com/p/1d037ab638ef】
spring-boot+logback+log4j2+MDC【https://www.jianshu.com/p/51da61a425ba】
参考博客:
https://blog.csdn.net/moshowgame/article/details/80304198
https://blog.csdn.net/zjh_746140129/article/details/81254987
https://blog.csdn.net/m0_38044453/article/details/81132523
网友评论