前言
本篇主要分两部分 ①springboot整合druid的代码配置,以及druid的监控页面演示;②对实际场景中多数据源的配置使用进行讲解。
一、springboot整合druid的演示demo
可以用idea快速生成一个可运行的demo工程,具体可以参考如何快速创建springboot项目
- 主要用到的依赖如下:
<dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jdbc</artifactId> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.2.17</version> </dependency> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>1.2.17</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> </dependencies>
- 配置数据库需要的配置文件application.yml(注意格式和空格)
spring: datasource: username: root password: root url: jdbc:mysql://localhost:3306/firsttest?serverTimezone=UTC&useUnicode=true@characterEncoding=utf-8 driver-class-name: com.mysql.jdbc.Driver type: com.alibaba.druid.pool.DruidDataSource 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
- 编写durid的启动配置类,加载数据库信息,和druid监控页面的初始化工作
package com.czing.jdbcdemo.config;
import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import org.springframework.boot.context.properties.ConfigurationProperties;
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 javax.servlet.Servlet;
import javax.sql.DataSource;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
/**
* @Description TODO
* @Author wangchengzhi
* @Date 2023/5/10 21:53
*/
@Configuration
public class DruidConfig {
@ConfigurationProperties(prefix = "spring.datasource")
@Bean
public DataSource druidDataSource(){
return new DruidDataSource();
}
/**
* @Author wangchengzhi
* @Description
* 向DruidConfig中添加代码,配置druid监控管理台的servlet
* @Date 22:12 2023/5/10
* @Param
* @return
**/
@Bean
public ServletRegistrationBean druidServletRegistrationBean(){
ServletRegistrationBean<Servlet> servletRegistrationBean = new ServletRegistrationBean<>(new StatViewServlet(),"/druid/*");
Map<String,String> initParams = new HashMap<>();
initParams.put("loginUsername","root");
initParams.put("loginPassword","root");
//后台允许谁可以访问
//initParams.put("allow", "localhost"):表示只有本机可以访问
//initParams.put("allow", ""):为空或者为null时,表示允许所有访问
initParams.put("allow","");
//deny:Druid 后台拒绝谁访问
//initParams.put("msb", "192.168.1.20");表示禁止此ip访问
servletRegistrationBean.setInitParameters(initParams);
return servletRegistrationBean;
}
@Bean
public FilterRegistrationBean webStatFilter() {
FilterRegistrationBean bean = new FilterRegistrationBean();
bean.setFilter(new WebStatFilter());
//exclusions:设置哪些请求进行过滤排除掉,从而不进行统计
Map<String, String> initParams = new HashMap<>();
initParams.put("exclusions", "*.js,*.css,/druid/*");
bean.setInitParameters(initParams);
//"/*" 表示过滤所有请求
bean.setUrlPatterns(Arrays.asList("/*"));
return bean;
}
}
- 编写controller类进行测试(此处使用jdbcTemplate进行演示)
package com.czing.jdbcdemo.controller;
import com.czing.jdbcdemo.mult.DataSource;
import com.czing.jdbcdemo.mult.DataSourceType;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
import java.util.Map;
/**
* @Description TODO
* @Author wangchengzhi
* @Date 2023/5/10 17:12
*/
@RestController
public class JDBCController {
@Autowired
JdbcTemplate jdbcTemplate;
/**
* @Author wangchengzhi
* @Description
* 使用springboot自带的jdbcTemplate实现数据库操作
* @Date 21:34 2023/5/10
* @Param
* @return
**/
@RequestMapping("/selectTest")
public List<Map<String, Object>> getTestAccount(){
String sql ="select * from account";
List<Map<String, Object>> maps = jdbcTemplate.queryForList(sql);
return maps;
}
}
- 启动项目,演示效果
项目启动日志:
druid的监控页面访问 http://localhost:8080/druid/sql.html
访问编写的controller测试类:http://localhost:8080/selectTest(访问之后可以观察druid监控页面的情况)
二、druid多数据源的配置使用
- 修改application.yml文件
spring: datasource: local: username: root password: root #注意多数据源配置的时候此处为jdbc-urljdbc-url: jdbc:mysql://localhost:3306/firsttest?serverTimezone=UTC&useUnicode=true@characterEncoding=utf-8 driver-class-name: com.mysql.jdbc.Driver type: com.alibaba.druid.pool.DruidDataSource remote: username: root password: root jdbc-url: jdbc:mysql://localhost:3306/test?serverTimezone=UTC&useUnicode=true@characterEncoding=utf-8 driver-class-name: com.mysql.jdbc.Driver type: com.alibaba.druid.pool.DruidDataSource
编写多数据源的配置类:
package com.czing.jdbcdemo.config;
import com.czing.jdbcdemo.mult.DataSourceType;
import com.czing.jdbcdemo.mult.DynamicDataSource;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import javax.sql.DataSource;
import java.util.HashMap;
import java.util.Map;
/**
* @Description TODO
* @Author wangchengzhi
* @Date 2023/5/10 23:07
*/
@Configuration
public class DataSourceConfig {
@Bean
@ConfigurationProperties("spring.datasource.remote")
public DataSource remoteDataSource() {
return DataSourceBuilder.create().build();
}
@Bean
@ConfigurationProperties("spring.datasource.local")
public DataSource localDataSource() {
return DataSourceBuilder.create().build();
}
@Bean(name = "dynamicDataSource")
@Primary
public DynamicDataSource dataSource(DataSource remoteDataSource, DataSource localDataSource) {
Map<Object, Object> targetDataSources = new HashMap<>();
targetDataSources.put(DataSourceType.REMOTE.name(), remoteDataSource);
targetDataSources.put(DataSourceType.LOCAL.name(), localDataSource);
return new DynamicDataSource(remoteDataSource, targetDataSources);
}
}
使用自定义注解,在查询方法的时候指定对应的数据源:
- 编写枚举类,用于指定数据源
package com.czing.jdbcdemo.mult;
public enum DataSourceType {
REMOTE,
LOCAL
}
- 数据源切换的处理类
package com.czing.jdbcdemo.mult;
/**
* @Description TODO
* @Author wangchengzhi
* @Date 2023/5/10 22:57
*/
public class DynamicDataSourceContextHolder {
/**
* 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<>();
/**
* 设置数据源变量
* @param dataSourceType
*/
public static void setDataSourceType(String dataSourceType){
System.out.printf("切换到{%s}数据源", dataSourceType);
CONTEXT_HOLDER.set(dataSourceType);
}
/**
* 获取数据源变量
* @return
*/
public static String getDataSourceType(){
return CONTEXT_HOLDER.get();
}
/**
* 清空数据源变量
*/
public static void clearDataSourceType(){
CONTEXT_HOLDER.remove();
}
}
- 数据源信息加载的实现
package com.czing.jdbcdemo.mult;
import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;
import javax.sql.DataSource;
import java.util.Map;
/**
* @Description TODO
* @Author wangchengzhi
* @Date 2023/5/10 23:03
*/
public class DynamicDataSource extends AbstractRoutingDataSource {
public DynamicDataSource(DataSource defaultTargetDataSource, Map<Object, Object> targetDataSources) {
super.setDefaultTargetDataSource(defaultTargetDataSource);
super.setTargetDataSources(targetDataSources);
// afterPropertiesSet()方法调用时用来将targetDataSources的属性写入resolvedDataSources中的
super.afterPropertiesSet();
}
/**
* @Author wangchengzhi
* @Description
* 根据Key获取数据源的信息
* @Date 23:06 2023/5/10
* @Param
* @return
**/
@Override
protected Object determineCurrentLookupKey() {
return DynamicDataSourceContextHolder.getDataSourceType();
}
}
- 多数据源的配置启动类,注入数据库配置信息
package com.czing.jdbcdemo.config;
import com.czing.jdbcdemo.mult.DataSourceType;
import com.czing.jdbcdemo.mult.DynamicDataSource;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import javax.sql.DataSource;
import java.util.HashMap;
import java.util.Map;
/**
* @Description TODO
* @Author wangchengzhi
* @Date 2023/5/10 23:07
*/
@Configuration
public class DataSourceConfig {
@Bean
@ConfigurationProperties("spring.datasource.remote")
public DataSource remoteDataSource() {
return DataSourceBuilder.create().build();
}
@Bean
@ConfigurationProperties("spring.datasource.local")
public DataSource localDataSource() {
return DataSourceBuilder.create().build();
}
@Bean(name = "dynamicDataSource")
@Primary
public DynamicDataSource dataSource(DataSource remoteDataSource, DataSource localDataSource) {
Map<Object, Object> targetDataSources = new HashMap<>();
targetDataSources.put(DataSourceType.REMOTE.name(), remoteDataSource);
targetDataSources.put(DataSourceType.LOCAL.name(), localDataSource);
return new DynamicDataSource(remoteDataSource, targetDataSources);
}
}
- 自定义注解
package com.czing.jdbcdemo.mult;
import java.lang.annotation.*;
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface DataSource {
/**
* 切换数据源名称
*/
DataSourceType value() default DataSourceType.REMOTE;
}
- AOP拦截类的实现
package com.czing.jdbcdemo.mult;
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.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
import java.lang.reflect.Method;
/**
* @Description TODO
* @Author wangchengzhi
* @Date 2023/5/11 10:09
*/
@Aspect
@Order(1)
@Component
public class DataSourceAspect {
@Pointcut("@annotation(com.czing.jdbcdemo.mult.DataSource)")
public void dsPointCut() {
}
@Around("dsPointCut()")
public Object around(ProceedingJoinPoint point) throws Throwable {
MethodSignature signature = (MethodSignature) point.getSignature();
Method method = signature.getMethod();
DataSource dataSource = method.getAnnotation(DataSource.class);
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();
}
}
}
- controller测试类的编写验证
package com.czing.jdbcdemo.controller;
import com.czing.jdbcdemo.mult.DataSource;
import com.czing.jdbcdemo.mult.DataSourceType;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
import java.util.Map;
/**
* @Description TODO
* @Author wangchengzhi
* @Date 2023/5/10 17:12
*/
@RestController
public class JDBCController {
@Autowired
JdbcTemplate jdbcTemplate;
/**
* @Author wangchengzhi
* @Description
* 使用springboot自带的jdbcTemplate实现数据库操作
* @Date 21:34 2023/5/10
* @Param
* @return
**/
@RequestMapping("/selectTest")
@DataSource(value=DataSourceType.LOCAL)
public List<Map<String, Object>> getTestAccount(){
String sql ="select * from account";
List<Map<String, Object>> maps = jdbcTemplate.queryForList(sql);
return maps;
}
/**
* @Author wangchengzhi
* @Description
* 使用springboot自带的jdbcTemplate实现数据库操作
* @Date 21:34 2023/5/10
* @Param
* @return
**/
@RequestMapping("/selectRemote")
@DataSource(DataSourceType.REMOTE)
public List<Map<String, Object>> getRemoteAccount(){
String sql ="select * from account";
List<Map<String, Object>> maps = jdbcTemplate.queryForList(sql);
return maps;
}
}
- 启动项目,分别访问两个接口查询不同的数据源
http://localhost:8080/selectTest 的访问数据:
http://localhost:8080/selectRemote 的访问数据
结语
以上为springboot实现druid配置查询的demo,并且演示了如何实现多数据源配置动态切换的代码实现,注意多数据源配置的时候url的配置为jdbc-url,其他运行中遇到的问题欢迎留言交流,希望对您的学习有所帮助。
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