一、修改gradle.build文件

1.1 添加如下配置

apply plugin: 'war'

1.2 修改依赖，将tomcat的依赖范围修改为providedCompile

dependencies {
    compile('org.springframework.boot:spring-boot-starter-web')
    providedCompile("org.springframework.boot:spring-boot-starter-tomcat")
    testCompile('org.springframework.boot:spring-boot-starter-test')

如图：

image.png

二、主类继承SpringBootServletInitializer，重写configure方法

@SpringBootApplication
public class ServerApplication extends SpringBootServletInitializer{

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

    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(ServerApplication.class);
    }

}

三、构建

进入项目路径，执行命令：gradle build。成功后会在build/libs下生成war包。