Application configuration class:
@SpringBootApplication
public class ServletInitializer extends SpringBootServletInitializer {
  @Override
  protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
    return application.sources(ServletInitializer.class);
  }
  public static void main(String[] args) throws Exception {
    SpringApplication.run(ServletInitializer.class, args);
  }
}

@Controller
public class BootController {
  @RequestMapping("/")
  @ResponseBody
  String home() {
    return "Hello World!";
  }
  public static void main(String[] args) throws Exception {
    SpringApplication.run(BootController.class, args);
  }
}

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>cn.creditease.springboot</groupId>
  <artifactId>springboot</artifactId>
  <packaging>war</packaging>
  <version>1.0</version>
  <name>Maven Webapp</name>
  <url>http://maven.apache.org</url>
  <properties>
  <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  <project_charset>UTF-8</project_charset>
  <maven.compiler.source>1.7</maven.compiler.source>
  <maven.compiler.target>1.7</maven.compiler.target>
  <tomcat.version>7.0.67</tomcat.version>
  </properties>
  <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.4.1.RELEASE</version>
  </parent>
  <dependencies>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-tomcat</artifactId>
      <scope>provided</scope>
    </dependency>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-test</artifactId>
      <scope>test</scope>
    </dependency>
  </dependencies>
  <repositories>
      <repository>
        <id>spring-releases</id>
        <name>Spring Releases</name>
        <url>http://repo.spring.io/libs-release-local</url>
        <snapshots>
          <enabled>true</enabled>
        </snapshots>
      </repository>
  </repositories>
</project>

server:
 port: 8080
 spring.mvc.view.prefix: /WEB-INF/jsp/
 spring.mvc.view.suffix: .jsp