这里我用的springboot项目,配置文件yml文件配置,gradle配置jar包依赖。

找了一天资料,终于整好了多数据源,步骤如下:

application.yml:

1 spring:
 2   datasource:
 3     driver-class-name: com.mysql.jdbc.Driver
 4     url: jdbc:mysql://localhost:3306/base?characterEncoding=utf8&useSSL=false          #5.5.45+, 5.6.26+ and 5.7.6+版本的mysql需要设置useSSL=false
 5     username: root
 6     password: 123456
 7     maximum-pool-size: 100            #datasource公共配置start
 8     max-idle: 10
 9     max-wait: 10000
10     min-idle: 5
11     initial-size: 5
12     validation-query: SELECT 1
13     test-on-borrow: false
14     test-while-idle: true
15     time-between-eviction-runs-millis: 18800           #datasource公共配置end
16   jpa:
17     database: MYSQL
18     show-sql: true
19     hibernate:
20       ddl-auto: update   #validate | update | create | create-drop
21       naming:
22         strategy: org.hibernate.cfg.DefaultNamingStrategy
23     properties:
24       hibernate:
25         dialect: org.hibernate.dialect.MySQL5Dialect  #Hibernate方言
26   freemarker:
27     allow-request-override: false
28     allow-session-override: false
29     cache: false
30     charset: UTF-8
31     check-template-location: true
32     content-type: text/html
33     enabled: true
34     expose-request-attributes: false
35     expose-session-attributes: false
36     expose-spring-macro-helpers: true
37     prefer-file-system-access: true
38     suffix: .html      #html静态页面
39     template-loader-path: classpath:/templates/       #模板路径
40     settings:
41       template_update_delay: 0
42       default_encoding: UTF-8
43       classic_compatible: true
44       date_format: yyyy-MM-dd
45       time_format: HH:mm:ss
46       datetime_format: yyyy-MM-dd HH:mm:ss
47 custom:
48   datasource:
49     names: ds1    #若需要添加其他数据源,可以直接在此处添加,用逗号隔开例如:(ds2,ds3),相应的下面的数据库配置只需要添加一个配置就可以了
50     ds1:
51       driver-class-name: com.mysql.jdbc.Driver
52       url: jdbc:mysql://localhost:3306/test1?characterEncoding=utf8&useSSL=false  #5.5.45+, 5.6.26+ and 5.7.6+版本的mysql需要设置useSSL=false
53       username: root
54       password: 123456

build.gradle添加相关依赖:

1     // mysql依赖
2     compile('mysql:mysql-connector-java')
3     // druid依赖
4     compile('com.alibaba:druid:1.0.15')
5     // jpa依赖
6     compile('org.springframework.boot:spring-boot-starter-data-jpa')
7

 

 

下面是数据源的配置:

1 import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;
 2 
 3 /**
 4  * 动态数据源
 5   */
 6 public class DynamicDataSource extends AbstractRoutingDataSource{
 7 
 8     /*
 9      * 代码中的determineCurrentLookupKey方法取得一个字符串,
10      * 该字符串将与配置文件中的相应字符串进行匹配以定位数据源,配置文件,即applicationContext.xml文件中需要要如下代码:(non-Javadoc)
11      */
12     @Override
13     protected Object determineCurrentLookupKey() {
14         return DynamicDataSourceContextHolder.getDataSourceType();
15     }
16 }

1 import org.aspectj.lang.JoinPoint;
 2 import org.aspectj.lang.annotation.After;
 3 import org.aspectj.lang.annotation.Aspect;
 4 import org.aspectj.lang.annotation.Before;
 5 import org.springframework.core.annotation.Order;
 6 import org.springframework.stereotype.Component;
 7 
 8 /**
 9  * 切换数据源Advice
10   */
11 @Aspect
12 @Order(-10)//保证该AOP在@Transactional之前执行
13 @Component
14 public class DynamicDataSourceAspect {
15 
16 
17     /*
18      * @Before("@annotation(ds)")
19      * 的意思是:
20      *
21      * @Before:在方法执行之前进行执行:
22      * @annotation(targetDataSource):
23      * 会拦截注解targetDataSource的方法,否则不拦截;
24      */
25     @Before("@annotation(targetDataSource)")
26     public void changeDataSource(JoinPoint point, TargetDataSource targetDataSource) throws Throwable {
27         //获取当前的指定的数据源;
28         String dsId = targetDataSource.value();
29         //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。
30         if (!DynamicDataSourceContextHolder.containsDataSource(dsId)) {
31             System.err.println("数据源[{}]不存在,使用默认数据源 > {}"+targetDataSource.value()+point.getSignature());
32         } else {
33             System.out.println("Use DataSource : {} > {}"+targetDataSource.value()+point.getSignature());
34             //找到的话,那么设置到动态数据源上下文中。
35             DynamicDataSourceContextHolder.setDataSourceType(targetDataSource.value());
36         }
37     }
38 
39     @After("@annotation(targetDataSource)")
40     public void restoreDataSource(JoinPoint point, TargetDataSource targetDataSource) {
41         System.out.println("Revert DataSource : {} > {}"+targetDataSource.value()+point.getSignature());
42         //方法执行完毕之后,销毁当前数据源信息,进行垃圾回收。
43         DynamicDataSourceContextHolder.clearDataSourceType();
44     }
45 
46 
47 }

1 import java.util.ArrayList;
 2 import java.util.List;
 3 
 4 /**
 5  * 动态数据源上下文
 6   */
 7 public class DynamicDataSourceContextHolder {
 8     /*
 9     * 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,
10     * 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。
11     */
12     private static final ThreadLocal<String> contextHolder = new ThreadLocal<>();
13 
14     /*
15      * 管理所有的数据源id;
16      * 主要是为了判断数据源是否存在;
17      */
18     public static List<String> dataSourceIds = new ArrayList<>();
19 
20 
21     /**
22      * 使用setDataSourceType设置当前的
23      */
24     public static void setDataSourceType(String dataSourceType){
25         contextHolder.set(dataSourceType);
26     }
27 
28 
29     /**
30      * 获取当前线程中的数据源
31      */
32     public static String getDataSourceType(){
33         return contextHolder.get();
34     }
35 
36     /**
37      * 删除当前线程池中的数据源
38       */
39     public static void clearDataSourceType(){
40         contextHolder.remove();
41     }
42 
43     public static boolean containsDataSource(String dataSourceId){
44         return dataSourceIds.contains(dataSourceId);
45     }
46 
47 }

import java.util.HashMap;
import java.util.Map;
import javax.sql.DataSource;

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
 */
public class DynamicDataSourceRegister implements ImportBeanDefinitionRegistrar, EnvironmentAware {
    //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 PropertyValues dataSourcePropertyValues;

    // 默认数据源
    private DataSource defaultDataSource;

    private Map<String, DataSource> customDataSources = new HashMap<String, DataSource>();

    /**
     * 加载多数据源配置
     */
    @Override
    public void setEnvironment(Environment environment) {
        System.out.println("DynamicDataSourceRegister.setEnvironment()");
        initDefaultDataSource(environment);
        initCustomDataSources(environment);
    }

    /**
     * 加载主数据源配置.
     */
    private void initDefaultDataSource(Environment env) {
        // 读取主数据源
        RelaxedPropertyResolver propertyResolver = new RelaxedPropertyResolver(env, "spring.datasource.");
        Map<String, Object> dsMap = new HashMap<String, Object>();
        dsMap.put("type", propertyResolver.getProperty("type"));
        dsMap.put("driverClassName", propertyResolver.getProperty("driverClassName"));
        dsMap.put("url", propertyResolver.getProperty("url"));
        dsMap.put("username", propertyResolver.getProperty("username"));
        dsMap.put("password", propertyResolver.getProperty("password"));

        //创建数据源;
        defaultDataSource = buildDataSource(dsMap);
        dataBinder(defaultDataSource, env);
    }

    /**
     * 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, "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);
        }
    }

    /**
     * 创建datasource.
     */
    @SuppressWarnings("unchecked")
    public DataSource buildDataSource(Map<String, Object> dsMap) {
        Object type = dsMap.get("type");
        if (type == null) {
            type = DATASOURCE_TYPE_DEFAULT;// 默认DataSource
        }
        Class<? extends DataSource> dataSourceType;

        try {
            dataSourceType = (Class<? extends DataSource>) Class.forName((String) type);
            String driverClassName = dsMap.get("driverClassName").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;
    }

    /**
     * 为DataSource绑定更多数据
     */
    private void dataBinder(DataSource dataSource, Environment env) {
        RelaxedDataBinder dataBinder = new RelaxedDataBinder(dataSource);
        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("driverClassName");
            values.remove("url");
            values.remove("username");
            values.remove("password");
            dataSourcePropertyValues = new MutablePropertyValues(values);
        }
        dataBinder.bind(dataSourcePropertyValues);
    }

    @Override
    public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
        System.out.println("DynamicDataSourceRegister.registerBeanDefinitions()");
        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();
        //添加属性:AbstractRoutingDataSource.defaultTargetDataSource
        mpv.addPropertyValue("defaultTargetDataSource", defaultDataSource);
        mpv.addPropertyValue("targetDataSources", targetDataSources);
        registry.registerBeanDefinition("dataSource", beanDefinition);
    }

}

1 import java.lang.annotation.Documented;
 2 import java.lang.annotation.ElementType;
 3 import java.lang.annotation.Retention;
 4 import java.lang.annotation.RetentionPolicy;
 5 import java.lang.annotation.Target;
 6 
 7 /**
 8  * 在方法上使用,用于指定使用哪个数据源
 9   */
10 @Target({ElementType.METHOD,ElementType.TYPE})
11 @Retention(RetentionPolicy.RUNTIME)
12 @Documented
13 public @interface TargetDataSource {
14     String value();
15 }

测试:

在Controller里:

1 @Resource
2     private TestService testService;

1 @Service
 2 public class TestService {
 3 
 4     @Resource
 5     private TestDao testDao;
 6     
 7 
 8     /**
 9      * 不指定数据源使用默认数据源
10      * @return
11      */
12     public List<User> getList(){
13         return testDao.getList();
14     }
15 
16     /**
17      * 指定数据源
18      * @return
19      */
20     @TargetDataSource("ds1")
21     public List<User> getListByDs1(){
22         //return testDao.getListByDs1();
23     }
24 
25 }

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.stereotype.Component;

@Component
public class TestDao {

    @Autowired
    private JdbcTemplate jdbcTemplate;

    /**
     * 不指定数据源使用默认数据源
     * @return
     */
    public List<User> getList(){
        String sql = "select * from user";
        return (List<User>) jdbcTemplate.query(sql, new RowMapper<User>(){
            @Override
            public User mapRow(ResultSet rs, int rowNum) throws SQLException {
                User user = new User();
                user.setId(rs.getLong("id"));
                user.setName(rs.getString("name"));;
                return user;
            }
        });
    }

    /**
     * 指定数据源
     * 在对应的service进行指定;
     * @return
     * @author SHANHY
     * @create  2016年1月24日
     */
    public List<User> getListByDs1(){
        /*
         * 这张表示复制的主库到ds1的,在ds中并没有此表.
         * 需要自己自己进行复制,不然会报错:Table 'test1.User1' doesn't exist
         */
        String sql = "select * from user";
        return (List<User>) jdbcTemplate.query(sql, new RowMapper<User>(){

            @Override
            public User mapRow(ResultSet rs, int rowNum) throws SQLException {
                User user = new User();
                user.setId(rs.getLong("id"));
                user.setName(rs.getString("name"));;
                return user;
            }
        });
    }
}

至于user表和user对应的实体类,自己创建一个就好。