1、添加maven依赖
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.1.3</version>
</dependency>
<!--properties动态注入-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-configuration-processor</artifactId>
<optional>true</optional>
</dependency>
<!--springBoot的aop-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-aop</artifactId>
</dependency>2、配置application.yml
# 数据库访问配置
# 主数据源，默认的
druid:
datasource:
type: com.alibaba.druid.pool.DruidDataSource
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://192.168.1.113:3306/test?useUnicode=true&characterEncoding=utf-8
username: root
password: root
# 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
initialSize: 5
minIdle: 5
maxActive: 20
# 配置获取连接等待超时的时间
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
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
validationQuery: SELECT 1 FROM DUAL
testWhileIdle: true
testOnBorrow: false
testOnReturn: false
# 打开PSCache，并且指定每个连接上PSCache的大小
poolPreparedStatements: true
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
filters: stat,wall,log4j
# 通过connectProperties属性来打开mergeSql功能；慢SQL记录
connectionProperties:
druid:
stat:
mergeSql: true
slowSqlMillis: 5000
# 合并多个DruidDataSource的监控数据
#多数据源
mysql-db:
datasource:
names: logic,dao
logic:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://192.168.1.113:3306/test1?useUnicode=true&characterEncoding=utf-8
username: root
password: root
dao:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://192.168.1.113:3306/test2?useUnicode=true&characterEncoding=utf-8
username: root
password: root
3、配置动态数据源
import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;
public class DynamicDataSource extends AbstractRoutingDataSource {
@Override
protected Object determineCurrentLookupKey() {
return DataSourceHolder.getDataSource();
}
}
4、配置数据源操作Holder
import java.util.ArrayList;
import java.util.List;
public class DataSourceHolder {
//线程本地环境
private static final ThreadLocal<String> contextHolders = new ThreadLocal<String>();
//数据源列表
public static List<String> dataSourceIds = new ArrayList<>();
//设置数据源
public static void setDataSource(String customerType) {
contextHolders.set(customerType);
}
//获取数据源
public static String getDataSource() {
return (String) contextHolders.get();
}
//清除数据源
public static void clearDataSource() {
contextHolders.remove();
}
public static boolean containsDataSource(String dataSourceId){
return dataSourceIds.contains(dataSourceId);
}
}
5、读取自定义数据源，并配置
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.MutablePropertyValues;
import org.springframework.beans.PropertyValues;
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.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.convert.ConversionService;
import org.springframework.core.convert.support.DefaultConversionService;
import org.springframework.core.env.Environment;
import org.springframework.stereotype.Component;
import javax.sql.DataSource;
import java.util.HashMap;
import java.util.Map;
@Component
@Configuration
public class DynamicDataSourceConfig implements EnvironmentAware {
private static final Logger logger = LoggerFactory.getLogger(DynamicDataSourceConfig.class);
// 默认数据源
private DataSource defaultDataSource;
// 属性值
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";
private ConversionService conversionService = new DefaultConversionService();
private Map<String, DataSource> customDataSources = new HashMap<>();
@Override
public void setEnvironment(Environment environment) {
initDefaultDatasource(environment);
initOtherDatasource(environment);
}
private void initOtherDatasource(Environment environment) {
RelaxedPropertyResolver propertyResolver = new RelaxedPropertyResolver(environment, "mysql-db.datasource.");
String dsPrefixs = propertyResolver.getProperty("names");
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, environment);
}
}
private void initDefaultDatasource(Environment environment) {
// 读取主数据源
RelaxedPropertyResolver propertyResolver = new RelaxedPropertyResolver(environment, "druid.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);
DataSourceHolder.dataSourceIds.add("ds1");
dataBinder(defaultDataSource, environment);
}
@SuppressWarnings("unchecked")
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) {
e.printStackTrace();
}
return null;
}
private void dataBinder(DataSource dataSource, Environment env){
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, "druid.datasource.").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);
}
@Bean(name = "dataSource")
public DynamicDataSource dataSource() {
DynamicDataSource dynamicDataSource = new DynamicDataSource();
// 默认数据源
dynamicDataSource.setDefaultTargetDataSource(defaultDataSource);
// 配置多数据源
Map<Object, Object> dsMap = new HashMap(5);
dsMap.put("ds1", defaultDataSource);
dsMap.putAll(customDataSources);
for (String key : customDataSources.keySet())
DataSourceHolder.dataSourceIds.add(key);
dynamicDataSource.setTargetDataSources(dsMap);
return dynamicDataSource;
}
}
6、动态切换关键——AOP进行切换
@Retention(RetentionPolicy.RUNTIME)
@Target({
ElementType.METHOD
})
public @interface DS {
String name() default "ds1";
}
import com.chen.config.dynamicDS.DataSourceHolder;
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.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
@Aspect
@Order(-1)// 保证该AOP在@Transactional之前执行
@Component
public class DynamicDataSourceAspect {
private static final Logger logger = LoggerFactory.getLogger(DynamicDataSourceAspect.class);
@Before("@annotation(ds)")
public void changeDataSource(JoinPoint point, DS ds) throws Throwable {
String dsId = ds.name();
if (!DataSourceHolder.containsDataSource(dsId)) {
logger.error("数据源[{}]不存在，使用默认数据源 > {}", ds.name(), point.getSignature());
} else {
logger.debug("Use DataSource : {} > {}", ds.name(), point.getSignature());
DataSourceHolder.setDataSource(ds.name());
}
}
@After("@annotation(ds)")
public void restoreDataSource(JoinPoint point, DS ds) {
logger.debug("Revert DataSource : {} > {}", ds.name(), point.getSignature());
DataSourceHolder.clearDataSource();
}
}
7、使用
1）、配置mapper
public interface DynamicDSMapper {
Integer queryJournal();
String queryUser();
String queryType();
}
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.chen.mapper.DynamicDSMapper">
<select id="queryJournal" resultType="java.lang.Integer">
SELECT uid FROM journal
</select>
<select id="queryUser" resultType="java.lang.String">
SELECT name FROM user
</select>
<select id="queryType" resultType="java.lang.String">
SELECT parent FROM p_type
</select>
</mapper>
2）、配置service
@Service
public class DynamicServciceImpl implements DynamicServcice {
@Autowired
private DynamicDSMapper dynamicDSMapper;
@DS()
public Integer ds1() {
return dynamicDSMapper.queryJournal();
}
@DS(name = "logic")
public String ds2() {
return dynamicDSMapper.queryUser();
}
@DS(name = "dao")
public String ds3() {
return dynamicDSMapper.queryType();
}
}
3）、单元测试调用
@RunWith(SpringRunner.class)
@SpringBootTest
public class TestDynamicDS {
private Logger logger = LoggerFactory.getLogger(TestDynamicDS.class);
//
@Autowired
private DynamicServcice dynamicServcice;
@Test
public void test() {
// Integer integer = dynamicServcice.ds1();
// logger.info("integer:"+integer);
// String ds2 = dynamicServcice.ds2();
// logger.info("ds2:"+ds2);
String ds3 = dynamicServcice.ds3();
logger.info("ds3:"+ds3);
}
}
4）、测试结果
以上为个人经验，希望能给大家一个参考，也希望大家多多支持编程网。
