Spring Boot学习笔记（十二）MyBatis Druid 多数据源 、Spring Boot 集成 Druid—— 概念与实战
MyBatis Druid 多数据源 、Spring Boot 集成 Druid—— 概念与实战
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Druid介绍
- Druid 是阿里巴巴开源平台上的一个项目，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。
- Druid 不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。在 Javad 的世界中 Druid 是目前最好的数据库连接池，在功能、性能、扩展性上都超过其他数据库连接池，包括 DBCP、C3P0、BoneCP、Proxool、JBoss、DataSource。
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用途
- 替换其他 Java 连接池，Druid 提供了一个高效、功能强大、可扩展性好的数据库连接池。可以监控数据库访问性能，Druid 内置提供了一个功能强大的 StatFilter 插件，能够详细统计 SQL 的执
行性能，这对于线上分析数据库访问性能有帮助。 - 数据库密码加密。直接把数据库密码写在配置文件中，容易导致安全问题。DruidDruiver 和 DruidDataSource 都支持 PasswordCallback。
- SQL 执行日志，Druid 提供了不同的 LogFilter，能够支持 Common-Logging、Log4j 和JdkLog，可以按需要选择相应的 LogFilter，监控应⽤用的数据库访问情况。
- 扩展 JDBC，如果对 JDBC 层有编程的需求，可以通过 Druid 提供的 Filter 机制，很方便编写JDBC 层的扩展插件。
- 替换其他 Java 连接池，Druid 提供了一个高效、功能强大、可扩展性好的数据库连接池。可以监控数据库访问性能，Druid 内置提供了一个功能强大的 StatFilter 插件，能够详细统计 SQL 的执
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初始化Spring Boot项目
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解压之后用IDEA打开 —— 项目目录总览（pom.xml文件未显示）
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pom.xml:
4.0.0 org.springframework.boot spring-boot-starter-parent 2.1.8.RELEASE wen druid 0.0.1-SNAPSHOT druid Demo project for Spring Boot 1.8 org.springframework.boot spring-boot-starter org.springframework.boot spring-boot-starter-test test org.springframework.boot spring-boot-starter-web org.mybatis.spring.boot mybatis-spring-boot-starter 1.2.0 com.alibaba druid 1.0.18 mysql mysql-connector-java log4j log4j 1.2.17 org.springframework.boot spring-boot-maven-plugin 值得一提的是：pom文件有个log4j文件包，这个必须要添加，因为后面的druid配置文件内有个log4j的值，不加上的话会导致配置文件出错而连不上druid
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application.properties:
# 主数据源，默认的 spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver spring.datasource.url=jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8&useSSL=true&serverTimezone = GMT spring.datasource.username=root spring.datasource.password= spring.datasource.filters=stat,wall,log4j # 更多数据源 custom.datasource.names=ds1,ds2 custom.datasource.ds1.driver-class-name=com.mysql.cj.jdbc.Driver custom.datasource.ds1.url=jdbc:mysql://localhost:3306/test1?useUnicode=true&characterEncoding=utf-8&useSSL=true&serverTimezone = GMT custom.datasource.ds1.username=root custom.datasource.ds1.password= custom.datasource.ds1.filters=stat,wall,log4j custom.datasource.ds2.driver-class-name=com.mysql.cj.jdbc.Driver custom.datasource.ds2.url=jdbc:mysql://localhost:3306/test2?useUnicode=true&characterEncoding=utf-8&useSSL=true&serverTimezone = GMT custom.datasource.ds2.username=root custom.datasource.ds2.password= spring.http.encoding.charset=utf-8 # 下面为连接池的补充设置，应用到上面所有数据源中 # 初始化大小，最小，最大 spring.datasource.initialSize=5 spring.datasource.minIdle=5 spring.datasource.maxActive=20 # 配置获取连接等待超时的时间 spring.datasource.maxWait=60000 # 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒 spring.datasource.timeBetweenEvictionRunsMillis=60000 # 配置一个连接在池中最小生存的时间，单位是毫秒 spring.datasource.minEvictableIdleTimeMillis=300000 spring.datasource.validationQuery=SELECT 1 FROM DUAL spring.datasource.testWhileIdle=true spring.datasource.testOnBorrow=false spring.datasource.testOnReturn=false # 打开PSCache，并且指定每个连接上PSCache的大小 spring.datasource.poolPreparedStatements=true spring.datasource.maxPoolPreparedStatementPerConnectionSize=20 # 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 # 通过connectProperties属性来打开mergeSql功能；慢SQL记录 spring.datasource.connectionProperties=druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000数据库连接的url账户密码根据自己的情况作出修改
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数据库设计
数据库设计为一个主表，两个从表，设定为都包含test表
建表语句：CREATE TABLE `test` ( `id` int(11) unsigned zerofill NOT NULL AUTO_INCREMENT, `name` varchar(36) NOT NULL, `age` int(2) NOT NULL, `gender` varchar(2) DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB AUTO_INCREMENT=9 DEFAULT CHARSET=utf8; -
实体类
entity包内的MasterUser.java 和 CustomUser.java：
package wen.druid.entity; public class MasterUser { private Integer id; private String name; private Integer age; private String gender; public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name == null ? null : name.trim(); } public Integer getAge() { return age; } public void setAge(Integer age) { this.age = age; } public String getGender() { return gender; } public void setGender(String gender) { this.gender = gender == null ? null : gender.trim(); } }package wen.druid.entity; public class CustomUser { private Integer id; private String name; private Integer age; private String gender; public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name == null ? null : name.trim(); } public Integer getAge() { return age; } public void setAge(Integer age) { this.age = age; } public String getGender() { return gender; } public void setGender(String gender) { this.gender = gender == null ? null : gender.trim(); } } -
底层xml文件
MasterUserMapper.xml
id, name,age,gender insert into test (id, name, age, gender) values (#{id,jdbcType=INTEGER}, #{name,jdbcType=VARCHAR}, #{age,jdbcType=INTEGER}, #{gender,jdbcType=VARCHAR}) insert into test id, name, age, gender, #{id,jdbcType=INTEGER}, #{name,jdbcType=VARCHAR}, #{age,jdbcType=INTEGER}, #{gender,jdbcType=VARCHAR}, delete from test where id = #{id,jdbcType=INTEGER} update test name = #{name,jdbcType=VARCHAR}, age = #{age,jdbcType=INTEGER}, gender = #{gender,jdbcType=VARCHAR}, update test set name = #{name,jdbcType=VARCHAR}, age = #{age,jdbcType=INTEGER}, gender = #{gender,jdbcType=VARCHAR} where id = #{id,jdbcType=INTEGER} CustomUserMapper.xml
id, name,age,gender insert into test (id, name, age, gender) values (#{id,jdbcType=INTEGER}, #{name,jdbcType=VARCHAR}, #{age,jdbcType=INTEGER}, #{gender,jdbcType=VARCHAR}) insert into test id, name, age, gender, #{id,jdbcType=INTEGER}, #{name,jdbcType=VARCHAR}, #{age,jdbcType=INTEGER}, #{gender,jdbcType=VARCHAR}, delete from test where id = #{id,jdbcType=INTEGER} update test name = #{name,jdbcType=VARCHAR}, age = #{age,jdbcType=INTEGER}, gender = #{gender,jdbcType=VARCHAR}, update test set name = #{name,jdbcType=VARCHAR}, age = #{age,jdbcType=INTEGER}, gender = #{gender,jdbcType=VARCHAR} where id = #{id,jdbcType=INTEGER} -
mapper层
package wen.druid.mapper; import wen.druid.entity.CustomUser; public interface CustomUserMapper { int deleteByPrimaryKey(Integer id); int insert(CustomUser customUser); int insertSelective(CustomUser customUser); CustomUser selectByPrimaryKey(Integer id); int updateByPrimaryKeySelective(CustomUser customUser); int updateByPrimaryKey(CustomUser customUser); }package wen.druid.mapper; import wen.druid.entity.MasterUser; public interface MasterUserMapper { int deleteByPrimaryKey(Integer id); int insert(MasterUser masterUser); int insertSelective(MasterUser masterUser); MasterUser selectByPrimaryKey(Integer id); int updateByPrimaryKeySelective(MasterUser masterUser); int updateByPrimaryKey(MasterUser masterUser); } -
service层
package wen.druid.service; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import wen.druid.entity.MasterUser; import wen.druid.mapper.MasterUserMapper; @Service public class MasterUserService { @Autowired private MasterUserMapper masterUserMapper; public MasterUser getMasterUser(Integer id) { return masterUserMapper.selectByPrimaryKey(id); } public int insert() { MasterUser masterUser = new MasterUser(); masterUser.setName("your papa"); masterUser.setAge(48); masterUser.setGender("M"); return masterUserMapper.insert(masterUser); } }package wen.druid.service; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import wen.druid.entity.CustomUser; import wen.druid.mapper.CustomUserMapper; @Service public class CustomUserService { @Autowired private CustomUserMapper customUserMapper; public CustomUser getCustomUser(Integer id) { return customUserMapper.selectByPrimaryKey(id); } public int insert() { CustomUser customUser = new CustomUser(); customUser.setName("mama"); customUser.setAge(49); customUser.setGender("F"); return customUserMapper.insert(customUser); } } -
config配置层文件
主数据源配置，需要加 @Primary：
MasterDataSourceConfig.java
package wen.druid.config; import com.alibaba.druid.pool.DruidDataSource; import org.apache.ibatis.session.SqlSessionFactory; import org.mybatis.spring.SqlSessionFactoryBean; import org.mybatis.spring.annotation.MapperScan; import org.springframework.beans.factory.annotation.Qualifier; import org.springframework.boot.context.properties.ConfigurationProperties; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.context.annotation.Primary; import org.springframework.core.io.support.PathMatchingResourcePatternResolver; import org.springframework.jdbc.datasource.DataSourceTransactionManager; import javax.sql.DataSource; @Configuration @MapperScan(basePackages = MasterDataSourceConfig.PACKAGES, sqlSessionFactoryRef = "masterSqlSessionFactory") public class MasterDataSourceConfig { static final String PACKAGES = "wen.druid.mapper"; private static final String MAPPER_LOCAL = "classpath:mapper/*.xml"; @Primary @Bean(name = "masterDataSource") @ConfigurationProperties("spring.datasource") public DruidDataSource druidDataSource() { return new DruidDataSource(); } @Primary @Bean(name = "masterTransactionManager") public DataSourceTransactionManager masterTransactionManager() { return new DataSourceTransactionManager(druidDataSource()); } @Primary @Bean(name = "masterSqlSessionFactory") public SqlSessionFactory masterSqlSessionFactory(@Qualifier("masterDataSource") DataSource dataSource) throws Exception { final SqlSessionFactoryBean sessionFactoryBean = new SqlSessionFactoryBean(); sessionFactoryBean.setDataSource(dataSource); sessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources(MAPPER_LOCAL)); return sessionFactoryBean.getObject(); } }CustomDataSourceConfig.java
从数据源配置 不需要加@Primary：
package wen.druid.config; import com.alibaba.druid.pool.DruidDataSource; import org.apache.ibatis.session.SqlSessionFactory; import org.mybatis.spring.SqlSessionFactoryBean; import org.mybatis.spring.annotation.MapperScan; import org.springframework.beans.factory.annotation.Qualifier; import org.springframework.boot.context.properties.ConfigurationProperties; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.core.io.support.PathMatchingResourcePatternResolver; import org.springframework.jdbc.datasource.DataSourceTransactionManager; @Configuration @MapperScan(basePackages = CustomDataSourceConfig.PACKAGES, sqlSessionFactoryRef = "customSqlSessionFactory") public class CustomDataSourceConfig { static final String PACKAGES = "wen.druid.mapper"; private static final String MAPPER_LOCAL = "classpath:mapper/*.xml"; @Bean(name = "customDataSource") @ConfigurationProperties("custom.datasource.ds1") public DruidDataSource druidDataSource() { return new DruidDataSource(); } @Bean(name = "customTransactionManager") public DataSourceTransactionManager customTransactionManager() { return new DataSourceTransactionManager(druidDataSource()); } @Bean(name = "customSqlSessionFactory") public SqlSessionFactory customSqlSessionFactory(@Qualifier("customDataSource") DruidDataSource dataSource) throws Exception { final SqlSessionFactoryBean sessionFactoryBean = new SqlSessionFactoryBean(); sessionFactoryBean.setDataSource(dataSource); sessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources(MAPPER_LOCAL)); return sessionFactoryBean.getObject(); } } -
servlet插件
DruidStatViewServlet.java
package wen.druid.config; import com.alibaba.druid.support.http.StatViewServlet; import javax.servlet.annotation.WebInitParam; import javax.servlet.annotation.WebServlet; @SuppressWarnings("serial") @WebServlet(urlPatterns = "/druid/*", initParams = { @WebInitParam(name = "allow", value = "192.168.16.110,127.0.0.1"),// IP白名单 (没有配置或者为空，则允许所有访问) @WebInitParam(name = "deny", value = "192.168.16.111"),// IP黑名单 (存在共同时，deny优先于allow) @WebInitParam(name = "loginUsername", value = "Stephanie"),// 用户名 @WebInitParam(name = "loginPassword", value = "admin"),// 密码 @WebInitParam(name = "resetEnable", value = "false")// 禁用HTML页面上的“Reset All”功能 }) public class DruidStatViewServlet extends StatViewServlet { }上文中的druid控制端用户名为：Stephanie，密码为admin
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过滤器DruidStatFilter.java
package wen.druid.config; import com.alibaba.druid.support.http.WebStatFilter; import javax.servlet.annotation.WebFilter; import javax.servlet.annotation.WebInitParam; @WebFilter(filterName = "druidWebStatFilter", urlPatterns = "/*", initParams = { @WebInitParam(name = "exclusions", value = "*.js,*.gif,*.jpg,*.bmp,*.png,*.css,*.ico,/druid/*")// 忽略资源 }) public class DruidStatFilter extends WebStatFilter { } -
启动类文件，需要加一个@ServletComponentScan,进行组件扫描
package wen.druid; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.web.servlet.ServletComponentScan; @SpringBootApplication @ServletComponentScan public class DruidApplication { public static void main(String[] args) { SpringApplication.run(DruidApplication.class, args); } } -
运行调试
- 开启启动类之后浏览器访问 http://localhost:8080/master/insert
- 由于insert方法返回是整数，所以运行成功如下图
- 查询id = 9的用户信息，以JSON数据返回
- 访问 http://localhost:8080/druid/login.html，输入DruidStatViewServlet.java提供的方法，进入到druid monitor界面
- 点击导航栏的SQL 监控，可以看到我刚刚操作过的SQL轨迹
项目地址：https://github.com/StephaineWYT/druid
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