启动程序出现以下错误：
017-05-06 22:44:18.868 WARN 41648 --- [ restartedMain] ationConfigEmbeddedWebApplicationContext : Exception encountered during context initialization - cancelling refresh attempt:org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Tomcat.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.tomcat.jdbc.pool.DataSource]: Factory method 'dataSource' threw exception; nested exception is org.springframework.boot.autoconfigure.jdbc.DataSourceProperties$DataSourceBeanCreationException: Cannot determine embedded database driver class for database type NONE. If you want an embedded database please put a supported one on the classpath. If you have database settings to be loaded from a particular profile you may need to active it (no profiles are currently active).
2017-05-06 22:44:18.871 INFO 41648 --- [ restartedMain] o.apache.catalina.core.StandardService : Stopping service Tomcat
2017-05-06 22:44:18.902 INFO 41648 --- [ restartedMain] utoConfigurationReportLoggingInitializer :
Error starting ApplicationContext. To display the auto-configuration report re-run your application with 'debug' enabled.
2017-05-06 22:44:18.907 ERROR 41648 --- [ restartedMain] o.s.b.d.LoggingFailureAnalysisReporter :
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APPLICATION FAILED TO START
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Description:
Cannot determine embedded database driver class for database type NONE
Action:
If you want an embedded database please put a supported one on the classpath. If you have database settings to be loaded from a particular profile you may need to active it (no profiles are currently active).
这是因为spring boot默认会加载org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration类，DataSourceAutoConfiguration类使用了@Configuration注解向spring注入了dataSource bean。因为工程中没有关于dataSource相关的配置信息，当spring创建dataSource bean因缺少相关的信息就会报错。
因为我仅仅只是使用spring boot来写一些很简单的例子来学习它，在Application类上增加@EnableAutoConfiguration(exclude={DataSourceAutoConfiguration.class})
阻止spring boot自动注入dataSource bean
