Click reason SpringBoot project can not start running tomcat

Because I want to use your browser's address bar mass participation, found that tomcat did not even start, after the exclusion of a number of factors, final positioning in the pom file Missing Dependency:

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

So add a dependent, and found that the lack of a version number, find the corresponding version of maven local repository via the following:

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <version>2.0.2.RELEASE</version>
        </dependency>

After the force update the project returned to normal, the built-in tomcat it can be started.

When there have been rerun of the following tips:

 

So be it, find the answer very tortuous process, but by thinking but also gain a lot of extra knowledge >>>