看一下this tutorial，下面是它们使用的@Configuration类：

@Configuration
public class MultipleMongoConfig {
    @Primary
    @Bean(name = "newdb1Properties")
    @ConfigurationProperties(prefix = "spring.data.mongodb.newdb1")
    public MongoProperties getNewDb1Props() throws Exception {
        return new MongoProperties();
    }

    @Bean(name = "newdb2Properties")
    @ConfigurationProperties(prefix = "spring.data.mongodb.newdb2")
    public MongoProperties getNewDb2Props() throws Exception {
        return new MongoProperties();
    }

    @Primary
    @Bean(name = "newdb1MongoTemplate")
    public MongoTemplate newdb1MongoTemplate() throws Exception {
        return new MongoTemplate(newdb1MongoDatabaseFactory(getNewDb1Props()));
    }

    @Bean(name ="newdb2MongoTemplate")
    public MongoTemplate newdb2MongoTemplate() throws Exception {
        return new MongoTemplate(newdb2MongoDatabaseFactory(getNewDb2Props()));
    }

    @Primary
    @Bean
    public MongoDatabaseFactory newdb1MongoDatabaseFactory(MongoProperties mongo) throws Exception {
        return new SimpleMongoClientDatabaseFactory(
                mongo.getUri()
        );
    }

    @Bean
    public MongoDatabaseFactory newdb2MongoDatabaseFactory(MongoProperties mongo) throws Exception {
        return new SimpleMongoClientDatabaseFactory(
                mongo.getUri()
        );
    }

}