spring boot2 启动报错

 

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2020-12-03 11:28:44.097 ERROR 75242 --- [           main] o.s.boot.SpringApplication               : Application run failed

org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.context.ApplicationContextException: Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean.
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:156)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:545)
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141)
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747)
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:315)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215)
	at com.wwl.consumer.ConsumerApplication.main(ConsumerApplication.java:18)
Caused by: org.springframework.context.ApplicationContextException: Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean.
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.getWebServerFactory(ServletWebServerApplicationContext.java:203)
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:179)
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:153)
	... 8 common frames omitted

Disconnected from the target VM, address: '127.0.0.1:63226', transport: 'socket'

Process finished with exit code 1

 

大概意思是springboot找不到内嵌的tomcat 未能加载嵌入的供web应用加载的空间，是因为缺少ServletWebServerFactory bean。 至于为啥找不到有点奇怪

 

pom.xml  配置

 

<dependency>
<groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
    <exclusions><!-- 去掉springboot默认配置 -->
        <exclusion>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
        </exclusion>
    </exclusions>
</dependency>

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

 

用两个方案可以解决 （在我这个问题上）

1. 去除tomcat的<scope>provided</scope> 标签

2. 在application.yml里面配置spring.main.web-application-type=none

 

具体原因还带排查

 

网上还有人说@SpringbootApplication 注解 和 @EnableAutoConfiguation 注解的

这是spring启动最基础的注解

@SpringbootApplication 包含了 @EnableAutoConfiguation 注解的

很多一些第三方依赖自动配置注入spring容器都是靠 @EnableAutoConfiguation 注解实现的