IntelliJ IDEA + Spring Boot + maven + (单)多数据源

落日映苍穹つ 2022-06-06 23:55 83阅读 0赞

![File-->New-->Project][File--_New--_Project]

![这里写图片描述][SouthEast]

![这里写图片描述][SouthEast 1]

![这里写图片描述][SouthEast 2]

![这里写图片描述][SouthEast 3]  
然后Finish , 在新窗口或者当前窗口打开都可以, 等待IDE配置

当IntelliJ IDEA配置完成之后,会有项目的分层目录

> 先创建并配置好一个maven项目

配置pom.xml文件

<?xml version="1.0" encoding="UTF-8"?>
    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    	<modelVersion>4.0.0</modelVersion>
    
    	<groupId>com.create</groupId>
    	<artifactId>createdatasource</artifactId>
    	<version>0.0.1-SNAPSHOT</version>
    	<packaging>jar</packaging>
    
    	<name>createdatasource</name>
    	<description>Demo project for Spring Boot</description>
    
    	<parent>
    		<groupId>org.springframework.boot</groupId>
    		<artifactId>spring-boot-starter-parent</artifactId>
    		<version>1.3.5.RELEASE</version>
    		<relativePath/> 
    	</parent>
    
    	<properties>
    		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    		<java.version>1.8</java.version>
    	</properties>
    
    	<dependencies>
    		<dependency>
    			<groupId>org.mybatis.spring.boot</groupId>
    			<artifactId>mybatis-spring-boot-starter</artifactId>
    		</dependency>
    		<dependency>
    			<groupId>org.springframework.boot</groupId>
    			<artifactId>spring-boot-starter-web</artifactId>
    		</dependency>
    		<dependency>
    			<groupId>org.springframework.boot</groupId>
    			<artifactId>spring-boot-starter-jdbc</artifactId>
    			
    		</dependency>
    		<dependency>
    			<groupId>org.springframework.boot</groupId>
    			<artifactId>spring-boot-starter-data-jpa</artifactId>
    		</dependency>
    		<dependency>
    			<groupId>mysql</groupId>
    			<artifactId>mysql-connector-java</artifactId>
    			<scope>runtime</scope>
    		</dependency>
    		<dependency>
    			<groupId>org.springframework.boot</groupId>
    			<artifactId>spring-boot-starter-test</artifactId>
    			<scope>test</scope>
    		</dependency>
    	</dependencies>
    
    	<build>
    		<plugins>
    			<plugin>
    				<groupId>org.springframework.boot</groupId>
    				<artifactId>spring-boot-maven-plugin</artifactId>
    			</plugin>
    			<plugin>
    				<groupId>org.apache.maven.plugins</groupId>
    				<artifactId>maven-jar-plugin</artifactId>
    				<configuration>
    					<archive>
    						<manifest>
    							<mainClass>com.create.CreatedatasourceApplication</mainClass>
    						</manifest>
    					</archive>
    				</configuration>
    			</plugin>
    		</plugins>
    	</build>
    </project>

> 编写启动类 CreatedatasourceApplication

package com.create;
    
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    @SpringBootApplication
    public class CreatedatasourceApplication {
    
    	public static void main(String[] args) {
    		SpringApplication.run(CreatedatasourceApplication.class, args);
    	}
    }

> 配置文件的设置 application.propertise  
> 但是一般我们会将application.propertise改为yaml文件即  
> application.yml, 同时新增两个文件  
> application-dev.yml, application-prod.yml, dev是测试环境 , prod是生产环境

application.yml配置文件

spring:
        profiles:
            active: prod

里面的prod就代表当前使用的配置文件是application-prod.yml, 即生产环境

server:
      port: 8380
    logging:
      path: D:\ideaworkspace\obs\logs
    spring:
      datasource:
        url: jdbc:mysql://数据库连接?allowMultiQueries=true&autoReconnect=true
        username: 用户名
        password: 密码
        driver-class: com.mysql.jdbc.Driver
        testWhileIdle : true
        validationQuery: SELECT 1
        sql-script-encoding: utf-8
        timeBetweenEvictionRunsMillis: 3600000
        ReadTimeout: 60000
        ConnectTimeout: 60000
    
      datasource1:
        url: jdbc:mysql://数据库连接?allowMultiQueries=true&autoReconnect=true
        username: 用户名
        password: 密码
        driver-class: com.mysql.jdbc.Driver
        testWhileIdle : true
        validationQuery: SELECT 1
        sql-script-encoding: utf-8
        timeBetweenEvictionRunsMillis: 3600000
        ReadTimeout: 60000
        ConnectTimeout: 60000

> 创建 DynamicDataSourceContextHolder (动态数据源上下文)类

package com.create.datasource;
    
    import java.util.ArrayList;
    import java.util.List;
    
    /**
     * Created by hcf on 2017/9/29.
     */
    public class DynamicDataSourceContextHolder {
    
        /*
         * 当使用ThreadLocal维护变量时，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> contextHolder = new ThreadLocal<String>();
        /*
         * 管理所有的数据源id;
         * 主要是为了判断数据源是否存在;
         */
        public static List<String> dataSourceIds = new ArrayList<String>();
    
        /**
         * 使用setDataSourceType设置当前的
         * @param dataSourceType
         */
        public static void setDataSourceType(String dataSourceType) {
            contextHolder.set(dataSourceType);
        }
    
        public static String getDataSourceType() {
            return contextHolder.get();
        }
    
        public static void clearDataSourceType() {
            contextHolder.remove();
        }
    
        /**
         * 判断指定DataSrouce当前是否存在
         */
        public static boolean containsDataSource(String dataSourceId){
            return dataSourceIds.contains(dataSourceId);
        }
    }

> 创建动态数据源类 DynamicDataSource.java 并使其继承(extends) AbstractRoutingDataSource

package com.create.datasource;
    
    import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;
    
    /**
     * Created by hcf on 2017/9/29.
     */
    public class DynamicDataSource extends AbstractRoutingDataSource{
        @Override
        protected Object determineCurrentLookupKey() {
            /*
            * DynamicDataSourceContextHolder代码中使用setDataSourceType
            * 设置当前的数据源，在路由类中使用getDataSourceType进行获取，
            *  交给AbstractRoutingDataSource进行注入使用。
            */
            return DynamicDataSourceContextHolder.getDataSourceType();
        }
    }

> 指定数据源注解类

package com.create.annotation;
    
    import java.lang.annotation.*;
    
    /**
     * Created by hcf on 2017/9/29.
     */
    
    @Target({ElementType.METHOD, ElementType.TYPE})
    @Retention(RetentionPolicy.RUNTIME)
    @Documented
    public @interface TargetDataSource {
        String value();
    }

> 创建切换数据源类 DynamicDataSourceAspect.java

package com.create.aspect;
    
    import com.create.annotation.TargetDataSource;
    import com.create.datasource.DynamicDataSourceContextHolder;
    import org.aspectj.lang.JoinPoint;
    import org.aspectj.lang.annotation.After;
    import org.aspectj.lang.annotation.Aspect;
    import org.aspectj.lang.annotation.Before;
    import org.springframework.core.annotation.Order;
    import org.springframework.stereotype.Component;
    
    /**
     * 切换数据源
     * Created by hcf on 2017/9/29.
     */
    
    @Aspect
    @Order(-10)
    @Component
    public class DynamicDataSourceAspect {
    
        /**
         * @Before("@annotation(targetDataSource)"):
         * 会拦截注解targetDataSource的方法
         *
         * @param point
         * @param targetDataSource
         * @throws Throwable
         */
        @Before("@annotation(targetDataSource)")
        public void changeDataSource(JoinPoint point, TargetDataSource targetDataSource) throws Throwable {
            //获取当前的指定的数据源;
            String dsId = targetDataSource.value();
            //如果不在我们注入的所有的数据源范围之内，那么输出警告信息，系统自动使用默认的数据源。
            if (!DynamicDataSourceContextHolder.containsDataSource(dsId)) {
                System.err.println("数据源[{}]不存在，使用默认数据源 > {}"+targetDataSource.value()+point.getSignature());
            } else {
                System.out.println("Use DataSource : {} > {}"+targetDataSource.value()+point.getSignature());
                //找到的话，那么设置到动态数据源上下文中。
                DynamicDataSourceContextHolder.setDataSourceType(targetDataSource.value());
            }
        }
    
        @After("@annotation(targetDataSource)")
        public void restoreDataSource(JoinPoint point, TargetDataSource targetDataSource) {
            System.out.println("Revert DataSource : {} > {}"+targetDataSource.value()+point.getSignature());
            //方法执行完毕之后，销毁当前数据源信息，进行垃圾回收。
            DynamicDataSourceContextHolder.clearDataSourceType();
        }
    }

[File--_New--_Project]: /images/20220607/6d044934961f4e84aad250b943d7085c.png
[SouthEast]: /images/20220607/bb6a4ff7c07d454391a59ae38a6171b5.png
[SouthEast 1]: /images/20220607/6111e73783a54063b031547bac084b58.png
[SouthEast 2]: /images/20220607/2567e240f29a4d438076582627315e5a.png
[SouthEast 3]: /images/20220607/ac4b1baebad545d287701c9e71f4609a.png