DynamicDataSourceRegister.java

package org.springboot.sample.datasource;

import java.util.HashMap;
import java.util.Map;

import javax.sql.DataSource;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
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;

/**
 * 动态数据源注册<br/>
 * 启动动态数据源请在启动类中（如SpringBootSampleApplication）
 * 添加 @Import(DynamicDataSourceRegister.class)
 *
 * @author 单红宇(365384722)
 * @myblog http://blog.csdn.net/catoop/
 * @create 2016年1月24日
 */
public class DynamicDataSourceRegister
		implements ImportBeanDefinitionRegistrar, EnvironmentAware {

	private static final Logger logger = LoggerFactory.getLogger(DynamicDataSourceRegister.class);

	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";
	// private static final Object DATASOURCE_TYPE_DEFAULT =
	// "com.zaxxer.hikari.HikariDataSource";

	// 数据源
	private DataSource defaultDataSource;
	private Map<String, DataSource> customDataSources = new HashMap<>();

	@Override
	public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
		Map<Object, Object> targetDataSources = new HashMap<Object, Object>();
		// 将主数据源添加到更多数据源中
		targetDataSources.put("dataSource", defaultDataSource);
		DynamicDataSourceContextHolder.dataSourceIds.add("dataSource");
		// 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("dataSource", beanDefinition);

		logger.info("Dynamic DataSource Registry");
	}

	/**
	 * 创建DataSource
	 *
	 * @param type
	 * @param driverClassName
	 * @param url
	 * @param username
	 * @param password
	 * @return
	 * @author SHANHY
	 * @create 2016年1月24日
	 */
	@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;
	}

	/**
	 * 加载多数据源配置
	 */
	@Override
	public void setEnvironment(Environment env) {
		initDefaultDataSource(env);
		initCustomDataSources(env);
	}

	/**
	 * 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);
	}
	
	/**
	 * 为DataSource绑定更多数据
	 *
	 * @param dataSource
	 * @param env
	 * @author SHANHY
	 * @create  2016年1月25日
	 */
	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, "spring.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);
	}

	/**
	 * 初始化更多数据源
	 *
	 * @author SHANHY
	 * @create 2016年1月24日
	 */
	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, "custom.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, env);
		}
	}

}