Spring Boot 战争在外部 tomcat 中出现异常

Question

I have developed a spring boot application in STS ide and i was able to run with the main class without any exception.

@SpringBootApplication
public class Java3Application {
    public static void main(String[] args) {
        SpringApplication.run(Java3Application.class, args);

    }
}

public class ServletInitializer extends SpringBootServletInitializer {

    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        setRegisterErrorPageFilter(false);  
        return application.sources(Java3Application.class);
    }
}

I generated the war of the same project using the below plugin and packaging :

<packaging>war</packaging>

<build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

Also have a dependency like this,

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

But the generated war is giving null pointer exception when one of my rest controllers are getting hit, but same is working fine with Main class. What is happening in my case?? Is my war packaging is wrong or in sufficient??

Answer 1

To make a spring boot application run in external tomcat, you have to extend it to SpringBootServletInitializer. Modify your code as below

@SpringBootApplication
public class Java3Application extends SpringBootServletInitializer{
    public static void main(String[] args) {
        SpringApplication.run(Java3Application.class, args);

    }
}