1. 引入依赖
<!-- 阿里数据库连接池 --><dependency><groupId>com.alibaba</groupId><artifactId>druid-spring-boot-starter</artifactId><version>1.2.16</version></dependency><!-- Mysql驱动包 --><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId></dependency>2. 配置数据源
spring:datasource:# 数据源基本配置username: 账号password: 密码url: jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=Asia/Shanghai# driver-class需要注意mysql驱动的版本(com.mysql.cj.jdbc.Driver 或 com.mysql.jdbc.Driver)driver-class-name: com.mysql.jdbc.Drivertype: com.alibaba.druid.pool.DruidDataSource# Druid的其他属性配置druid:# 初始化时建立物理连接的个数initial-size: 10# 连接池的最小空闲数量min-idle: 5# 连接池最大连接数量max-active: 20# 获取连接时最大等待时间，单位毫秒max-wait: 60000# 申请连接的时候检测，如果空闲时间大于timeBetweenEvictionRunsMillis，执行validationQuery检测连接是否有效。test-while-idle: true# 既作为检测的间隔时间又作为testWhileIdel执行的依据time-between-eviction-runs-millis: 60000# 销毁线程时检测当前连接的最后活动时间和当前时间差大于该值时，关闭当前连接(配置连接在池中的最小生存时间)min-evictable-idle-time-millis: 30000# 用来检测数据库连接是否有效的sql 必须是一个查询语句(oracle中为 select 1 from dual)validation-query: SELECT 1 FROM DUAL# 申请连接时会执行validationQuery检测连接是否有效,开启会降低性能,默认为truetest-on-borrow: false# 归还连接时会执行validationQuery检测连接是否有效,开启会降低性能,默认为truetest-on-return: false# 是否缓存preparedStatement, 也就是PSCache,PSCache对支持游标的数据库性能提升巨大，比如说oracle,在mysql下建议关闭。pool-prepared-statements: false# 置监控统计拦截的filters，去掉后监控界面sql无法统计，stat: 监控统计、Slf4j:日志记录、waLL: 防御sqL注入filters: stat,wall,slf4j# 要启用PSCache，必须配置大于0，当大于0时，poolPreparedStatements自动触发修改为true。在Druid中，不会存在Oracle下PSCache占用内存过多的问题，可以把这个数值配置大一些，比如说100max-pool-prepared-statement-per-connection-size: -1# 合并多个DruidDataSource的监控数据use-global-data-source-stat: true# 通过connectProperties属性来打开mergeSql功能；慢SQL记录connect-properties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000web-stat-filter:# 是否启用StatFilter默认值trueenabled: true# 添加过滤规则url-pattern: /*# 忽略过滤的格式exclusions: /druid/*,*.js,*.gif,*.jpg,*.png,*.css,*.icostat-view-servlet:# 是否启用StatViewServlet默认值trueenabled: true# 访问路径为/druid时，跳转到StatViewServleturl-pattern: /druid/*# 是否能够重置数据reset-enable: false# 需要账号密码才能访问控制台，默认为rootlogin-username: rootlogin-password: 123456# IP白名单allow: 127.0.0.1# IP黑名单（共同存在时，deny优先于allow）deny:
配置好之后 Druid 会通过 DruidDataSourceAutoConfigure 自动装配
package com.alibaba.druid.spring.boot.autoconfigure;@Configuration
@ConditionalOnClass(DruidDataSource.class)
@AutoConfigureBefore(DataSourceAutoConfiguration.class)
@EnableConfigurationProperties({DruidStatProperties.class, DataSourceProperties.class})
@Import({DruidSpringAopConfiguration.class,DruidStatViewServletConfiguration.class,DruidWebStatFilterConfiguration.class,DruidFilterConfiguration.class})
public class DruidDataSourceAutoConfigure {private static final Logger LOGGER = LoggerFactory.getLogger(DruidDataSourceAutoConfigure.class);@Bean(initMethod = "init")@ConditionalOnMissingBeanpublic DataSource dataSource() {LOGGER.info("Init DruidDataSource");return new DruidDataSourceWrapper();}
}3. Druid 配置多数据源
属性配置
# 数据源配置
spring:datasource:type: com.alibaba.druid.pool.DruidDataSourcedriverClassName: com.mysql.cj.jdbc.Driverdruid:# 主库数据源master:url: jdbc:mysql://localhost:3306/large_screen_monitor?useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useSSL=true&serverTimezone=GMT%2B8username: rootpassword: root# 从库数据源slave:# 从数据源开关/默认关闭enabled: falseurl: username: password: # 初始连接数initialSize: 5# 最小连接池数量minIdle: 10# 最大连接池数量maxActive: 20# 配置获取连接等待超时的时间maxWait: 60000# 配置连接超时时间connectTimeout: 30000# 配置网络超时时间socketTimeout: 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timeBetweenEvictionRunsMillis: 60000# 配置一个连接在池中最小生存的时间，单位是毫秒minEvictableIdleTimeMillis: 300000# 配置一个连接在池中最大生存的时间，单位是毫秒maxEvictableIdleTimeMillis: 900000# 配置检测连接是否有效validationQuery: SELECT 1 FROM DUALtestWhileIdle: truetestOnBorrow: falsetestOnReturn: falsewebStatFilter: enabled: truestatViewServlet:enabled: true# 设置白名单，不填则允许所有访问allow:url-pattern: /druid/*# 控制台管理用户名和密码login-username: webserverlogin-password: 123456filter:stat:enabled: true# 慢SQL记录log-slow-sql: trueslow-sql-millis: 1000merge-sql: truewall:config:multi-statement-allow: true
package com.test.framework.config.properties;import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Configuration;
import com.alibaba.druid.pool.DruidDataSource;/*** druid 配置属性*/
@Configuration
public class DruidProperties
{@Value("${spring.datasource.druid.initialSize}")private int initialSize;@Value("${spring.datasource.druid.minIdle}")private int minIdle;@Value("${spring.datasource.druid.maxActive}")private int maxActive;@Value("${spring.datasource.druid.maxWait}")private int maxWait;@Value("${spring.datasource.druid.connectTimeout}")private int connectTimeout;@Value("${spring.datasource.druid.socketTimeout}")private int socketTimeout;@Value("${spring.datasource.druid.timeBetweenEvictionRunsMillis}")private int timeBetweenEvictionRunsMillis;@Value("${spring.datasource.druid.minEvictableIdleTimeMillis}")private int minEvictableIdleTimeMillis;@Value("${spring.datasource.druid.maxEvictableIdleTimeMillis}")private int maxEvictableIdleTimeMillis;@Value("${spring.datasource.druid.validationQuery}")private String validationQuery;@Value("${spring.datasource.druid.testWhileIdle}")private boolean testWhileIdle;@Value("${spring.datasource.druid.testOnBorrow}")private boolean testOnBorrow;@Value("${spring.datasource.druid.testOnReturn}")private boolean testOnReturn;public DruidDataSource dataSource(DruidDataSource datasource){/** 配置初始化大小、最小、最大 */datasource.setInitialSize(initialSize);datasource.setMaxActive(maxActive);datasource.setMinIdle(minIdle);/** 配置获取连接等待超时的时间 */datasource.setMaxWait(maxWait);/** 配置驱动连接超时时间，检测数据库建立连接的超时时间，单位是毫秒 */datasource.setConnectTimeout(connectTimeout);/** 配置网络超时时间，等待数据库操作完成的网络超时时间，单位是毫秒 */datasource.setSocketTimeout(socketTimeout);/** 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 */datasource.setTimeBetweenEvictionRunsMillis(timeBetweenEvictionRunsMillis);/** 配置一个连接在池中最小、最大生存的时间，单位是毫秒 */datasource.setMinEvictableIdleTimeMillis(minEvictableIdleTimeMillis);datasource.setMaxEvictableIdleTimeMillis(maxEvictableIdleTimeMillis);/*** 用来检测连接是否有效的sql，要求是一个查询语句，常用select 'x'。如果validationQuery为null，testOnBorrow、testOnReturn、testWhileIdle都不会起作用。*/datasource.setValidationQuery(validationQuery);/** 建议配置为true，不影响性能，并且保证安全性。申请连接的时候检测，如果空闲时间大于timeBetweenEvictionRunsMillis，执行validationQuery检测连接是否有效。 */datasource.setTestWhileIdle(testWhileIdle);/** 申请连接时执行validationQuery检测连接是否有效，做了这个配置会降低性能。 */datasource.setTestOnBorrow(testOnBorrow);/** 归还连接时执行validationQuery检测连接是否有效，做了这个配置会降低性能。 */datasource.setTestOnReturn(testOnReturn);return datasource;}
}
数据源枚举
package com.test.common.enums;/*** 数据源*/
public enum DataSourceType
{/*** 主库*/MASTER,/*** 从库*/SLAVE
}动态数据源
继承 AbstractRoutingDataSource 就可以实现动态数据源了
在使用 DynamicDataSource 时，会调用determineCurrentLookupKey 方法拿到具体数据源的key，然后使用对应的数据源；如果没有对应的数据源，会使用 DynamicDataSource 设置的默认数据源
package com.test.framework.datasource;import java.util.Map;
import javax.sql.DataSource;
import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;/*** 动态数据源*/
public class DynamicDataSource extends AbstractRoutingDataSource
{public DynamicDataSource(DataSource defaultTargetDataSource, Map<Object, Object> targetDataSources){super.setDefaultTargetDataSource(defaultTargetDataSource);super.setTargetDataSources(targetDataSources);super.afterPropertiesSet();}@Overrideprotected Object determineCurrentLookupKey(){return DynamicDataSourceContextHolder.getDataSourceType();}
}
数据源切换
package com.test.framework.datasource;import org.slf4j.Logger;
import org.slf4j.LoggerFactory;/*** 数据源切换处理*/
public class DynamicDataSourceContextHolder
{public static final Logger log = LoggerFactory.getLogger(DynamicDataSourceContextHolder.class);/*** 使用ThreadLocal维护变量，ThreadLocal为每个使用该变量的线程提供独立的变量副本，* 所以每一个线程都可以独立地改变自己的副本，而不会影响其它线程所对应的副本。*/private static final ThreadLocal<String> CONTEXT_HOLDER = new ThreadLocal<>();/*** 设置数据源的变量*/public static void setDataSourceType(String dsType){log.info("切换到{}数据源", dsType);CONTEXT_HOLDER.set(dsType);}/*** 获得数据源的变量*/public static String getDataSourceType(){return CONTEXT_HOLDER.get();}/*** 清空数据源变量*/public static void clearDataSourceType(){CONTEXT_HOLDER.remove();}
}
数据源配置类
package com.test.framework.config;import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.sql.DataSource;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.spring.boot.autoconfigure.DruidDataSourceBuilder;
import com.alibaba.druid.spring.boot.autoconfigure.properties.DruidStatProperties;
import com.alibaba.druid.util.Utils;
import com.test.common.enums.DataSourceType;
import com.test.common.utils.spring.SpringUtils;
import com.test.framework.config.properties.DruidProperties;
import com.test.framework.datasource.DynamicDataSource;/*** druid 配置多数据源*/
@Configuration
public class DruidConfig
{@Bean@ConfigurationProperties("spring.datasource.druid.master")public DataSource masterDataSource(DruidProperties druidProperties){DruidDataSource dataSource = DruidDataSourceBuilder.create().build();return druidProperties.dataSource(dataSource);}@Bean@ConfigurationProperties("spring.datasource.druid.slave")@ConditionalOnProperty(prefix = "spring.datasource.druid.slave", name = "enabled", havingValue = "true")public DataSource slaveDataSource(DruidProperties druidProperties){DruidDataSource dataSource = DruidDataSourceBuilder.create().build();return druidProperties.dataSource(dataSource);}@Bean(name = "dynamicDataSource")@Primarypublic DynamicDataSource dataSource(DataSource masterDataSource){Map<Object, Object> targetDataSources = new HashMap<>();targetDataSources.put(DataSourceType.MASTER.name(), masterDataSource);setDataSource(targetDataSources, DataSourceType.SLAVE.name(), "slaveDataSource");return new DynamicDataSource(masterDataSource, targetDataSources);}/*** 设置数据源* * @param targetDataSources 备选数据源集合* @param sourceName 数据源名称* @param beanName bean名称*/public void setDataSource(Map<Object, Object> targetDataSources, String sourceName, String beanName){try{DataSource dataSource = SpringUtils.getBean(beanName);targetDataSources.put(sourceName, dataSource);}catch (Exception e){}}/*** 去除监控页面底部的广告*/@SuppressWarnings({ "rawtypes", "unchecked" })@Bean@ConditionalOnProperty(name = "spring.datasource.druid.statViewServlet.enabled", havingValue = "true")public FilterRegistrationBean removeDruidFilterRegistrationBean(DruidStatProperties properties){// 获取web监控页面的参数DruidStatProperties.StatViewServlet config = properties.getStatViewServlet();// 提取common.js的配置路径String pattern = config.getUrlPattern() != null ? config.getUrlPattern() : "/druid/*";String commonJsPattern = pattern.replaceAll("\\*", "js/common.js");final String filePath = "support/http/resources/js/common.js";// 创建filter进行过滤Filter filter = new Filter(){@Overridepublic void init(javax.servlet.FilterConfig filterConfig) throws ServletException{}@Overridepublic void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)throws IOException, ServletException{chain.doFilter(request, response);// 重置缓冲区，响应头不会被重置response.resetBuffer();// 获取common.jsString text = Utils.readFromResource(filePath);// 正则替换banner, 除去底部的广告信息text = text.replaceAll("<a.*?banner\"></a><br/>", "");text = text.replaceAll("powered.*?shrek.wang</a>", "");response.getWriter().write(text);}@Overridepublic void destroy(){}};FilterRegistrationBean registrationBean = new FilterRegistrationBean();registrationBean.setFilter(filter);registrationBean.addUrlPatterns(commonJsPattern);return registrationBean;}
}
SpringBoot Bean工具类
package com.test.common.utils.spring;import org.springframework.aop.framework.AopContext;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;/*** spring工具类 方便在非spring管理环境中获取bean* * @author webserver*/
@Component
public final class SpringUtils implements BeanFactoryPostProcessor, ApplicationContextAware
{/** Spring应用上下文环境 */private static ConfigurableListableBeanFactory beanFactory;private static ApplicationContext applicationContext;@Overridepublic void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {SpringUtils.beanFactory = beanFactory;}@Overridepublic void setApplicationContext(ApplicationContext applicationContext) throws BeansException {SpringUtils.applicationContext = applicationContext;}/*** 获取对象** @param name* @return Object 一个以所给名字注册的bean的实例* @throws org.springframework.beans.BeansException**/@SuppressWarnings("unchecked")public static <T> T getBean(String name) throws BeansException{return (T) beanFactory.getBean(name);}/*** 获取类型为requiredType的对象** @param clz* @return* @throws org.springframework.beans.BeansException**/public static <T> T getBean(Class<T> clz) throws BeansException{T result = (T) beanFactory.getBean(clz);return result;}/*** 如果BeanFactory包含一个与所给名称匹配的bean定义，则返回true** @param name* @return boolean*/public static boolean containsBean(String name){return beanFactory.containsBean(name);}/*** 判断以给定名字注册的bean定义是一个singleton还是一个prototype。 如果与给定名字相应的bean定义没有被找到，将会抛出一个异常（NoSuchBeanDefinitionException）** @param name* @return boolean* @throws org.springframework.beans.factory.NoSuchBeanDefinitionException**/public static boolean isSingleton(String name) throws NoSuchBeanDefinitionException{return beanFactory.isSingleton(name);}/*** @param name* @return Class 注册对象的类型* @throws org.springframework.beans.factory.NoSuchBeanDefinitionException**/public static Class<?> getType(String name) throws NoSuchBeanDefinitionException{return beanFactory.getType(name);}/*** 如果给定的bean名字在bean定义中有别名，则返回这些别名** @param name* @return* @throws org.springframework.beans.factory.NoSuchBeanDefinitionException**/public static String[] getAliases(String name) throws NoSuchBeanDefinitionException{return beanFactory.getAliases(name);}/*** 获取aop代理对象* * @param invoker* @return*/@SuppressWarnings("unchecked")public static <T> T getAopProxy(T invoker){return (T) AopContext.currentProxy();}/*** 获取当前的环境配置，无配置返回null** @return 当前的环境配置*/public static String[] getActiveProfiles(){return applicationContext.getEnvironment().getActiveProfiles();}/*** 获取当前的环境配置，当有多个环境配置时，只获取第一个** @return 当前的环境配置*/public static String getActiveProfile(){final String[] activeProfiles = getActiveProfiles();return (activeProfiles != null && activeProfiles.lenth > 0) ? activeProfiles[0] : null;}/*** 获取配置文件中的值** @param key 配置文件的key* @return 当前的配置文件的值**/public static String getRequiredProperty(String key){return applicationContext.getEnvironment().getRequiredProperty(key);}
}
手动切换数据源
在需要切换数据源的方法中使用DynamicDataSourceContextHolder类实现手动切换
public List<SysUser> selectUserList(SysUser user)
{DynamicDataSourceContextHolder.setDataSourceType(DataSourceType.SLAVE.name());List<SysUser> userList = userMapper.selectUserList(user);DynamicDataSourceContextHolder.clearDataSourceType();return userList;
}实现注解切换数据源
自定义注解
package com.test.common.annotation;import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import com.test.common.enums.DataSourceType;/*** 自定义多数据源切换注解** 优先级：先方法，后类，如果方法覆盖了类上的数据源类型，以方法的为准，否则以类上的为准** @author webserver*/
@Target({ ElementType.METHOD, ElementType.TYPE })
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
public @interface DataSource
{/*** 切换数据源名称*/public DataSourceType value() default DataSourceType.MASTER;
}
根据注解实现切点
import java.util.Objects;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
import com.test.common.annotation.DataSource;
import com.test.framework.datasource.DynamicDataSourceContextHolder;/*** 多数据源处理* * @author webserver*/
@Aspect
@Order(1)
@Component
public class DataSourceAspect
{protected Logger logger = LoggerFactory.getLogger(getClass());@Pointcut("@annotation(com.jy.common.annotation.DataSource)"+ "|| @within(com.jy.common.annotation.DataSource)")public void dsPointCut(){}@Around("dsPointCut()")public Object around(ProceedingJoinPoint point) throws Throwable{DataSource dataSource = getDataSource(point);if (dataSource != null){DynamicDataSourceContextHolder.setDataSourceType(dataSource.value().name());}try{return point.proceed();}finally{// 销毁数据源 在执行方法之后DynamicDataSourceContextHolder.clearDataSourceType();}}/*** 获取需要切换的数据源*/public DataSource getDataSource(ProceedingJoinPoint point){MethodSignature signature = (MethodSignature) point.getSignature();DataSource dataSource = AnnotationUtils.findAnnotation(signature.getMethod(), DataSource.class);if (Objects.nonNull(dataSource)){return dataSource;}return AnnotationUtils.findAnnotation(signature.getDeclaringType(), DataSource.class);}
}
在需要使用多数据源方法或类上添加@DataSource注解，其中value用来表示数据源
@DataSource(value = DataSourceType.SLAVE)
public List<SysUser> selectUserList(SysUser user)
{return userMapper.selectUserList(user);
}
