Spring Boot War deployed to Tomcat

Question

I am trying to deploy a Spring Boot app to Tomcat, because I want to deploy to AWS. I created a WAR file, but it does not seem to run on Tomcat, even though it is visible.

Details:
0. Here is my app:

@Configuration
@ComponentScan
@EnableAutoConfiguration
public class App {
    public static void main(String[] args) {
        SpringApplication.run(SampleController.class, args);
    }
}

@Controller
@EnableAutoConfiguration
public class SampleController {
    @RequestMapping("/help")
    @ResponseBody
    String home() {
        String input = "Hi! Please use 'tag','check' and 'close' resources.";
        return input;
    }
}

application.properties has following:

server.port=${port:7777}

1. After reading a number of pages and question-answers I added following to my POM:

   http://maven.apache.org/xsd/maven-4.0.0.xsd"> 4.0.0

   <groupId>com.niewlabs</groupId>
   <artifactId>highlighter</artifactId>
   <version>1.0-SNAPSHOT</version>
   
   <packaging>war</packaging>
   
   <properties>
       <java.version>1.8</java.version>
   </properties>    
   <parent>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-starter-parent</artifactId>
       <version>1.1.9.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>
   </dependencies>
   

2. I ran"mvn package"and got WAR file (size 250Mb), which I put into "webapps" folder.

3. I started Tomcat and am able to see my app listed, in my case "/highlighter-1.0-SNAPSHOT".
4. Clicking on the link for the app results in "Status 404" page.
5. When I run Spring Boot app just by itself, without container it runs on localhost:7777, but there is nothing there when I run it in Tomcat.

Update: There is another reference. Not sure how useful it is.

Answer 1

Your Application.java class should extend the SpringBootServletInitializer class ex:

public class Application extends SpringBootServletInitializer {}

Answer 2

This guide explains in detail how to deploy Spring Boot app on Tomcat:
http://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/#howto-create-a-deployable-war-file

Essentially I needed to add following class:

public class WebInitializer extends SpringBootServletInitializer {   
    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(App.class);
    }    
}

Also I added following property to POM:

<properties>        
    <start-class>mypackage.App</start-class>
</properties>

Answer 3

public class Application extends SpringBootServletInitializer {}

just extends the SpringBootServletInitializer. It will works in your AWS/tomcat

Answer 4

Update 2018-02-03 with Spring Boot 1.5.8.RELEASE.

In pom.xml, you need to tell Spring plugin when it is building that it is a war file by change package to war, like this:

<packaging>war</packaging>

Also, you have to excluded the embedded tomcat while building the package by adding this:

    <!-- to deploy as a war in tomcat -->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-tomcat</artifactId>
        <scope>provided</scope>
    </dependency>

The full runable example is in here https://www.surasint.com/spring-boot-create-war-for-tomcat/

Answer 5

After following the guide (or using Spring Initializr), I had a WAR that worked on my local computer, but didn't work remote (running on Tomcat).

There was no error message, it just said "Spring servlet initializer was found", but didn't do anything at all.

17-Aug-2016 16:58:13.552 INFO [main] org.apache.catalina.core.StandardEngine.startInternal Starting Servlet Engine: Apache Tomcat/8.5.4
17-Aug-2016 16:58:13.593 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployWAR Deploying web application archive /opt/tomcat/webapps/ROOT.war
17-Aug-2016 16:58:16.243 INFO [localhost-startStop-1] org.apache.jasper.servlet.TldScanner.scanJars At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.

and

17-Aug-2016 16:58:16.301 INFO [localhost-startStop-1] org.apache.catalina.core.ApplicationContext.log 2 Spring WebApplicationInitializers detected on classpath
17-Aug-2016 16:58:21.471 INFO [localhost-startStop-1] org.apache.catalina.core.ApplicationContext.log Initializing Spring embedded WebApplicationContext
17-Aug-2016 16:58:25.133 INFO [localhost-startStop-1] org.apache.catalina.core.ApplicationContext.log ContextListener: contextInitialized()
17-Aug-2016 16:58:25.133 INFO [localhost-startStop-1] org.apache.catalina.core.ApplicationContext.log SessionListener: contextInitialized()

Nothing else happened. Spring Boot just didn't run.

Apparently I compiled the server with Java 1.8, and the remote computer had Java 1.7.

After compiling with Java 1.7, it started working.

<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    <java.version>1.7</java.version> <!-- added this line -->
    <start-class>myapp.SpringApplication</start-class>
</properties>

Answer 6

I had same problem and i find out solution by following this guide . I run with goal in maven.

clean package

Its worked for me Thanq