2、多数据源配置之自定义注解aop拦截进行配置

待我称王封你为后i 2022-05-26 07:49 152阅读 0赞

## 前言 ##

其实这里可以使用很多库的，但是我这里却只用了2个库，一个库one作为默认库，另一个库作为指定库，当然one库也可以指定。先提供给类注解，如果方法上有注解则先看方法里面的

## 1、自定义注解 ##

package com.hlj.many.datasourse.data;
    
    /**
     * @Description  自定义注解
     * @Date   2018/4/24 下午6:09.
     */
    
    public enum DataSource {
    
        ONE("one"),
        TWO("two"),
        ;
    
        private String name;
    
        DataSource(String name){
            this.name = name;
        }
    
        public String getName(){
            return this.name;
        }
    
    }

## 2、配置数据源信息 ##

server.port=8888
    
    ########################################################
    ### jpa
    ########################################################
    spring.jpa.database=MYSQL
    spring.jpa.show-sql=true
    spring.jpa.hibernate.ddl-auto =update
    spring.jpa.hibernate.naming-strategy=org.hibernate.cfg.ImprovedNamingStrategy
    spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5Dialect
    
    
    
    # 主数据源
    spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
    spring.datasource.url=jdbc:mysql://localhost:3306/com_hlj_many_database-one
    spring.datasource.username=root
    spring.datasource.password=123456
    spring.datasource.driver-class-name=com.mysql.jdbc.Driver
    
    
    
    # 其他数据源
    hlj.datasource.names=one,two
    #datasource one
    hlj.datasource.one.type=com.alibaba.druid.pool.DruidDataSource
    hlj.datasource.one.url=jdbc:mysql://localhost:3306/com_hlj_many_database-one
    hlj.datasource.one.username=root
    hlj.datasource.one.password=123456
    hlj.datasource.one.driver-class-name=com.mysql.jdbc.Driver
    
    #datasource two
    hlj.datasource.two.type=com.alibaba.druid.pool.DruidDataSource
    hlj.datasource.two.url=jdbc:mysql://localhost:3306/com_hlj_many_database-two
    hlj.datasource.two.username=root
    hlj.datasource.two.password=123456
    hlj.datasource.two.driver-class-name=com.mysql.jdbc.Driver

## 3、多个数据源的存取单例模式 ##

package com.hlj.many.datasourse.data;
    
    import java.util.ArrayList;
    import java.util.List;
    import java.util.Stack;
    
    /**
     * @Description  类似于单例模式数据源
     * @Date   2018/4/24 下午6:10.
     */
    
    public class DynamicDataSourceContextHolder {
    
        private static final ThreadLocal<String> contextHolder = new ThreadLocal<String>();
        private static final ThreadLocal<Stack<String>> stackHolder = new ThreadLocal<>();
        public static List<String> dataSourceIds = new ArrayList<>();
    
        public static void setDataSource(String dataSourceType) {
            // 保存当前线程上一次的数据源，用于清除时恢复上次的上线文
            if (contextHolder.get() != null){
                Stack<String> stack = stackHolder.get();
                if (stack == null){
                    stack = new Stack<>();
                    stackHolder.set(stack);
                }
                stack.push(contextHolder.get());
            }
            contextHolder.set(dataSourceType);
        }
    
        public static String getDataSourceType() {
            return contextHolder.get();
        }
    
        public static void clearDataSource() {
            // 清除本次的数据源
            contextHolder.remove();
            // 从栈中拿出上一次的数据源
            Stack<String> stack = stackHolder.get();
            if (stack != null){
                if (stack.isEmpty()){
                    stackHolder.remove();
                }else{
                    String pop = stack.pop();
                    contextHolder.set(pop);
                    if (stack.isEmpty()){
                        stackHolder.remove();
                    }
                }
            }
        }
    
        /**
         * 判断指定DataSrouce当前是否存在
         * @param dataSourceName
         * @return
         */
        public static boolean containsDataSource(String dataSourceName){
            return dataSourceIds.contains(dataSourceName);
        }
    
    }

## 4、获取动态数据源 ##

package com.hlj.many.datasourse.data;
    
    import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;
    
    /**
     * @Description  获取动态数据源
     * @Date   2018/4/24 下午6:11.
     */
    
    public class DynamicDataSource extends AbstractRoutingDataSource {
        @Override
        protected Object determineCurrentLookupKey() {
            return DynamicDataSourceContextHolder.getDataSourceType();
        }
    }

## 5、数据源的设置和绑定，提供给springboot启动的时候进行导入和加载 ##

package com.hlj.many.datasourse.data;
    
    import lombok.extern.slf4j.Slf4j;
    import org.apache.commons.lang3.StringUtils;
    import org.springframework.beans.MutablePropertyValues;
    import org.springframework.beans.PropertyValues;
    import org.springframework.beans.factory.support.BeanDefinitionRegistry;
    import org.springframework.beans.factory.support.GenericBeanDefinition;
    import org.springframework.boot.autoconfigure.jdbc.DataSourceBuilder;
    import org.springframework.boot.bind.RelaxedDataBinder;
    import org.springframework.boot.bind.RelaxedPropertyResolver;
    import org.springframework.context.EnvironmentAware;
    import org.springframework.context.annotation.ImportBeanDefinitionRegistrar;
    import org.springframework.core.convert.ConversionService;
    import org.springframework.core.convert.support.DefaultConversionService;
    import org.springframework.core.env.Environment;
    import org.springframework.core.type.AnnotationMetadata;
    import javax.sql.DataSource;
    import java.util.HashMap;
    import java.util.Map;
    
    /**
     * Created by fengchuanbo on 2017/5/8.
     */
    @Slf4j
    public class DynamicDataSourceRegistrar implements ImportBeanDefinitionRegistrar,EnvironmentAware {
    
        private ConversionService conversionService = new DefaultConversionService();
        private PropertyValues dataSourcePropertyValues;
    
        // 如配置文件中未指定数据源类型，使用该默认值
        private static final Object DATASOURCE_TYPE_DEFAULT = "org.apache.tomcat.jdbc.pool.DataSource";
    
        // 数据源
        private DataSource defaultDataSource;
        private Map<String, DataSource> customDataSources = new HashMap<>();
        private static final String DEFAULT_DATASOURCE_NAME = com.hlj.many.datasourse.data.DataSource.ONE.getName();
    
        @Override
        public void setEnvironment(Environment environment) {
            initDefaultDataSource(environment);
            initCustomDataSources(environment);
        }
    
        @Override
        public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
            Map<Object, Object> targetDataSources = new HashMap<>();
            // 将主数据源添加到更多数据源中
            targetDataSources.put(DEFAULT_DATASOURCE_NAME, defaultDataSource);
            DynamicDataSourceContextHolder.dataSourceIds.add(DEFAULT_DATASOURCE_NAME);
            // 添加更多数据源
            targetDataSources.putAll(customDataSources);
            for (String key : customDataSources.keySet()) {
                DynamicDataSourceContextHolder.dataSourceIds.add(key);
            }
    
            // 创建DynamicDataSource
            GenericBeanDefinition beanDefinition = new GenericBeanDefinition();
            beanDefinition.setBeanClass(DynamicDataSource.class);
            beanDefinition.setSynthetic(true);
            MutablePropertyValues mpv = beanDefinition.getPropertyValues();
            mpv.addPropertyValue("defaultTargetDataSource", defaultDataSource);
            mpv.addPropertyValue("targetDataSources", targetDataSources);
            registry.registerBeanDefinition(DEFAULT_DATASOURCE_NAME, beanDefinition);
    
            if (log.isInfoEnabled()) {
                log.info("Dynamic DataSource Registry");
            }
        }
    
        /**
         * 初始化主数据源
         *
         * @author SHANHY
         * @create 2016年1月24日
         */
        private void initDefaultDataSource(Environment env) {
            // 读取主数据源
            RelaxedPropertyResolver propertyResolver = new RelaxedPropertyResolver(env, "spring.datasource.");
            Map<String, Object> dsMap = new HashMap<>();
            dsMap.put("type", propertyResolver.getProperty("type"));
            dsMap.put("driver-class-name", propertyResolver.getProperty("driver-class-name"));
            dsMap.put("url", propertyResolver.getProperty("url"));
            dsMap.put("username", propertyResolver.getProperty("username"));
            dsMap.put("password", propertyResolver.getProperty("password"));
    
            defaultDataSource = buildDataSource(dsMap);
            dataBinder(defaultDataSource, env,"spring.datasource");
        }
    
        /**
         * 为DataSource绑定更多数据
         * @param dataSource
         * @param env
         */
        private void dataBinder(DataSource dataSource, Environment env, String prefix){
            RelaxedDataBinder dataBinder = new RelaxedDataBinder(dataSource);
            //dataBinder.setValidator(new LocalValidatorFactory().run(this.applicationContext));
            dataBinder.setConversionService(conversionService);
            dataBinder.setIgnoreNestedProperties(false);//false
            dataBinder.setIgnoreInvalidFields(false);//false
            dataBinder.setIgnoreUnknownFields(true);//true
            if(dataSourcePropertyValues == null){
                Map<String, Object> rpr = new RelaxedPropertyResolver(env, prefix).getSubProperties(".");
                Map<String, Object> values = new HashMap<>(rpr);
                // 排除已经设置的属性
                values.remove("type");
                values.remove("driver-class-name");
                values.remove("url");
                values.remove("username");
                values.remove("password");
                dataSourcePropertyValues = new MutablePropertyValues(values);
            }
            dataBinder.bind(dataSourcePropertyValues);
        }
    
        /**
         * 初始化更多数据源
         */
        private void initCustomDataSources(Environment env) {
            // 读取配置文件获取更多数据源，也可以通过defaultDataSource读取数据库获取更多数据源
            RelaxedPropertyResolver propertyResolver = new RelaxedPropertyResolver(env, "hlj.datasource.");
            String dsPrefixs = propertyResolver.getProperty("names");
            if (StringUtils.isEmpty(dsPrefixs)) return;
            for (String dsPrefix : dsPrefixs.split(",")) {// 多个数据源
                Map<String, Object> dsMap = propertyResolver.getSubProperties(dsPrefix + ".");
                DataSource ds = buildDataSource(dsMap);
                customDataSources.put(dsPrefix, ds);
                dataBinder(ds, env,"hlj.datasource." + dsPrefix);
            }
        }
    
        /**
         * 创建DataSource
         * @return
         */
        public DataSource buildDataSource(Map<String, Object> dsMap) {
            try {
                Object type = dsMap.get("type");
                if (type == null)
                    type = DATASOURCE_TYPE_DEFAULT;// 默认DataSource
    
                Class<? extends DataSource> dataSourceType;
                dataSourceType = (Class<? extends DataSource>) Class.forName((String) type);
    
                String driverClassName = dsMap.get("driver-class-name").toString();
                String url = dsMap.get("url").toString();
                String username = dsMap.get("username").toString();
                String password = dsMap.get("password").toString();
    
                DataSourceBuilder factory = DataSourceBuilder.create()
                        .driverClassName(driverClassName)
                        .url(url).username(username)
                        .password(password)
                        .type(dataSourceType);
                return factory.build();
            } catch (ClassNotFoundException e) {
                throw new RuntimeException(e);
            }
        }
    }

## 6、springBoot启动，扫描jpa和导入DynamicDataSourceRegistrar.class ##

package com.hlj.many.datasourse;
    
    import com.hlj.many.datasourse.data.DynamicDataSourceRegistrar;
    import org.mybatis.spring.annotation.MapperScan;
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.boot.autoconfigure.domain.EntityScan;
    import org.springframework.context.annotation.Import;
    import org.springframework.context.annotation.ImportResource;
    import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
    import org.springframework.transaction.annotation.EnableTransactionManagement;
    
    @SpringBootApplication
    @EnableTransactionManagement
    @EnableJpaRepositories(basePackages = {"com.hlj.many.datasourse.dataresource.dao"})
    @EntityScan(basePackages = "com.hlj.many.datasourse.dataresource.dao")
    @Import({DynamicDataSourceRegistrar.class}) //导入数据库
    public class ComHljManyDatasourceApplication {
    
    	public static void main(String[] args) {
    		SpringApplication.run(ComHljManyDatasourceApplication.class, args);
    	}
    }

## 7、添加mybatis ##

package com.hlj.many.datasourse.config;
    
    import org.apache.commons.lang3.ArrayUtils;
    import org.mybatis.spring.SqlSessionFactoryBean;
    import org.mybatis.spring.annotation.MapperScan;
    import org.mybatis.spring.mapper.MapperScannerConfigurer;
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.core.io.Resource;
    
    import javax.sql.DataSource;
    import java.io.IOException;
    
    
    
    /**
     * @Description
     * @Author HealerJean
     * @Date 2018/4/24  下午5:44.
     */
    @Configuration
    public class MybatisConfig {
    
        @Bean
        public MapperScannerConfigurer mapperScannerConfigurer(){
            MapperScannerConfigurer configurer = new MapperScannerConfigurer();
            configurer.setBasePackage("com.hlj.many.datasourse.dataresource.dao.*");
            return configurer;
        }
    
        @Bean
        public SqlSessionFactoryBean sessionFactory(DataSource dataSource, ApplicationContext applicationContext) throws IOException {
            SqlSessionFactoryBean sessionFactoryBean = new SqlSessionFactoryBean();
            sessionFactoryBean.setDataSource(dataSource);
            sessionFactoryBean.setConfigLocation(applicationContext.getResource("classpath:mybatis.xml"));
    
            Resource[] resources = ArrayUtils.addAll(
                    applicationContext.getResources("classpath*:com/hlj/many/datasourse/dataresource/dao/**/*.xml")
            );
            sessionFactoryBean.setMapperLocations(resources);
            return sessionFactoryBean;
        }
    }

## 测试方法也挺多的，如果需要请直接下载代码 ##

## [下载代码][Link 1] ##

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[Link 1]: https://gitee.com/HealerJean/CodeDownLoad/raw/master/2019-04-19-20_2_%E5%A4%9A%E6%95%B0%E6%8D%AE%E6%BA%90%E9%85%8D%E7%BD%AE%E4%B9%8B%E8%87%AA%E5%AE%9A%E4%B9%89%E6%B3%A8%E8%A7%A3aop%E6%8B%A6%E6%88%AA%E8%BF%9B%E8%A1%8C%E9%85%8D%E7%BD%AE/com-hlj-annotation-datasource.zip
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