java - 由于缺少 ServletWebServerFactory bean，即使使用@springbootapplication，我也无法启动 ServletWebServerApplicationContext

Question

这是我的主课即使我正在使用应该 Autowiring 所有依赖项的 springbootApplication 注释，我也会收到此错误

@EntityScan(basePackages = {"com.valentine.model","com.valentine.messenger"})
@SpringBootApplication(scanBasePackages = {"com.valentine.gram",
    "com.valentine.service", "com.valentine"})
@EnableJpaRepositories("com.valentine.dao")
@EnableTransactionManagement
public class MainApp {

    public static void main(String[] args) {
        SpringApplication.run(MainApp.class, args);
    }

}

下面是我的堆栈跟踪和 pom 文件，这是一个模块化项目，所以我发布主要的 pom 文件

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2018-11-09 23:10:47.131 ERROR 9266 --- [           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:155) ~[spring-boot-2.0.4.RELEASE.jar:2.0.4.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:544) ~[spring-context-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140) ~[spring-boot-2.0.4.RELEASE.jar:2.0.4.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:762) [spring-boot-2.0.4.RELEASE.jar:2.0.4.RELEASE]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:398) [spring-boot-2.0.4.RELEASE.jar:2.0.4.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:330) [spring-boot-2.0.4.RELEASE.jar:2.0.4.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1258) [spring-boot-2.0.4.RELEASE.jar:2.0.4.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1246) [spring-boot-2.0.4.RELEASE.jar:2.0.4.RELEASE]
    at com.valentine.gram.MainApp.main(MainApp.java:19) [classes/:na]
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:204) ~[spring-boot-2.0.4.RELEASE.jar:2.0.4.RELEASE]
    at  

现在pom文件在下面

  <dependency>
            <groupId>com.valentine.mygram</groupId>
            <artifactId>main-app</artifactId>
            <version>${project.version}</version>
        </dependency>

        <!--spring-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-test</artifactId>
            <version>2.0.4.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>${spring.version}</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>${spring.version}</version>
        </dependency>


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

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

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

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

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

        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-core</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-web</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-config</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <!--servlets-->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>${javax.servlet-api.version}</version>
        </dependency>

关于问题可能是什么以及我如何解决问题的任何建议

Answer 1

据我所知，在 spring boot 中不需要使用像

这样的额外注释

@EntityScan(basePackages = {"com.valentine.model","com.valentine.messenger"})
@SpringBootApplication(scanBasePackages = {"com.valentine.gram",
    "com.valentine.service", "com.valentine"})
@EnableJpaRepositories("com.valentine.dao")

我认为 @SpringBootApplication 足以处理所有这些注释!

而且我不知道你为什么要在 spring boot 中使用所有这些依赖项

     <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-web</artifactId>
                <version>${spring.version}</version>
            </dependency>

            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-test</artifactId>
                <version>2.0.4.RELEASE</version>
            </dependency>

            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-test</artifactId>
                <version>${spring.version}</version>
                <scope>test</scope>
            </dependency>

            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-context</artifactId>
                <version>${spring.version}</version>
            </dependency>

            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-webmvc</artifactId>
                <version>${spring.version}</version>
            </dependency>
            <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-web</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-config</artifactId>
            <version>${spring.version}</version>
        </dependency>

所有这些依赖项都是针对 spring MVC 的，而不是针对 spring boot 的!并且在 spring boot 中无需提及依赖项的版本。喜欢

    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>${javax.servlet-api.version}</version>
     </dependency>

你只能这样写，spring boot会自动处理!

 <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
    </dependency>