Error starting ApplicationContext. To display the conditions report re-run your application。。。。

从springboot官网上通过模版下载了项目，模版里包含了war, mysql, mybatis，下载完成后，直接在本地运行，报错：

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2019-05-28 14:57:45.822 [main] ERROR o.s.b.diagnostics.LoggingFailureAnalysisReporter - 

***************************
APPLICATION FAILED TO START
***************************

Description:

Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured.

Reason: Failed to determine a suitable driver class


Action:

Consider the following:
	If you want an embedded database (H2, HSQL or Derby), please put it on the classpath.
	If you have database settings to be loaded from a particular profile you may need to activate it (no profiles are currently active).

Disconnected from the target VM, address: '127.0.0.1:27565', transport: 'socket'

Process finished with exit code 1

springboot 2.0+中使用jdbc-url配置数据库URL, 1.5中使用url,不然会导致一个错误。jdbcUrl is required with driverClassName

创建一个DataSourceConfig后，再运行，正常

package com.example.demo.config;

import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.sql.DataSource;

@Configuration
public class DataSourceConfig {
    @Bean("MyDataSource")
    @Qualifier("MyDataSource")
    @ConfigurationProperties(prefix="spring.datasource")
    public DataSource getMyDataSource(){
        return DataSourceBuilder.create().build();
    }
}