创建spring boot项目启动报错遇到的问题

1、Spring boot，Mybatis 启动报错 Failed to auto-configure a DataSource

    ***************************  
    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).  

　　解决方法：

　　注解这样写：@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})

2、非法反射，报错信息

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by org.springframework.cglib.core.ReflectUtils$1 (file:/C:/Users/%e5%85%b3%e6%96%87%e5%b3%b0/.m2/repository/org/springframework/spring-core/5.0.6.RELEASE/spring-core-5.0.6.RELEASE.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int,java.security.ProtectionDomain)
WARNING: Please consider reporting this to the maintainers of org.springframework.cglib.core.ReflectUtils$1
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release

　　警告信息，暂时没影响

3、idea运行springBoot项目报错 Process finished with exit code 0

　　Deleting provided scope of spring-boot-starter-tomcat dependency helps me.

　　在pom.xml中添加，然后导入

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-tomcat</artifactId>
</dependency>

4、alt + enter 导入类

　　在使用idea开发java项目的时候，经常需要导入jdk或者是第三方类库的类，如果是自己手工导入的话，非常麻烦，效率很低，下面来介绍下如何设置idea，就可以实现自动导入

　　设置自动导入的方式，来自动批量导入，打开idea的settings设置对话框

　　在左上角的输入框中输入auto import关键字搜索，找到Editor>General>Auto Import

　　勾选上add unambiguous imports on the fly选项，点击确认，关闭对话框

　　在设置自动导入的窗口，还有一个Optimize imports on the fly选项，也可以勾选上，可以帮助我们自动去除不需要的导入类