I've followed the Getting Started tutorial on spring.io for building REEST services https://spring.io/guides/gs/rest-service/. The problem is that this tutorial only explain how to produce a standalone running jar with tomcat embedded using spring boot.
Is there a way to create a project from scratch to produce a war to deploy for instance on an already existing tomcat instance?
PS: I had found a previous thread Spring RESTful Service as a WAR instead of JAR in Tomcat on stackoverflow concerning the very same issue. The problem is that the accepted answers and suggestions doesn't exactly solve my problem, since I'm not looking for ways to modify the standalone-app spring boot project so that it works on an external tomcat container, but would like to find a 'cleaner' solution not involving spring boot at all. (I'm not exactly sure how to behave here, being still quite new at stackoverflow. I hope that opening a new question is the correct procedure).
You don't need Spring Boot to create a rest controller.
Please follow the spring framework documentation on how to setup MVC
https://docs.spring.io/spring/docs/current/spring-framework-reference/web.html#spring-web
The MVC setup (the DispatcherServlet) depends on your spring version, you can either use xml or you can setup programmatically:
https://docs.spring.io/spring/docs/current/spring-framework-reference/web.html#mvc-servlet
Once this is setup, you can add a rest controller to your application. Note that a rest controller (the @RestController annotation) is a stereotype annotation that combines @ResponseBody and @Controller, in other words the Controller returns an object in the response body instead of returning a view.
This is a perfect example explaining what I said above:
http://www.programming-free.com/2014/01/spring-mvc-40-restful-web-services.html
Here is another example:
Directory Layout:
.
├── ./pom.xml
└── ./src
└── ./src/main
├── ./src/main/java
│ └── ./src/main/java/biz
│ └── ./src/main/java/biz/tugay
│ └── ./src/main/java/biz/tugay/restfulspring
│ └── ./src/main/java/biz/tugay/restfulspring/config
│ ├── ./src/main/java/biz/tugay/restfulspring/config/RestfulHello.java
│ └── ./src/main/java/biz/tugay/restfulspring/config/WebAppInitalizer.java
└── ./src/main/webapp
└── ./src/main/webapp/WEB-INF
└── ./src/main/webapp/WEB-INF/web.xml
pom.xml
<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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>biz.tugay</groupId>
<artifactId>restfulSpring</artifactId>
<packaging>war</packaging>
<version>1.0-SNAPSHOT</version>
<name>restfulSpring Maven Webapp</name>
<url>http://maven.apache.org</url>
<dependencies>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.0.1</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>4.3.16.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>4.3.16.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>4.3.16.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>4.3.16.RELEASE</version>
</dependency>
</dependencies>
<build>
<finalName>restfulSpring</finalName>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
<plugin>
<groupId>org.eclipse.jetty</groupId>
<artifactId>jetty-maven-plugin</artifactId>
<version>9.2.1.v20140609</version>
</plugin>
</plugins>
</build>
</project>
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
version="3.0">
</web-app>
WebAppInitalizer.java
package biz.tugay.restfulspring.config;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;
@Configuration
@EnableWebMvc
@ComponentScan("biz.tugay.restfulspring")
public class WebAppInitalizer extends AbstractAnnotationConfigDispatcherServletInitializer {
@Override
protected String[] getServletMappings() {
return new String[]{"/*"};
}
@Override
protected Class<?>[] getRootConfigClasses() {
return new Class<?>[]{WebAppInitalizer.class};
}
@Override
protected Class<?>[] getServletConfigClasses() {
return new Class[0];
}
}
RestfulHello.java
package biz.tugay.restfulspring.config;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
@RequestMapping(value = "/")
public class RestfulHello {
@RequestMapping(value = "hello")
public ResponseEntity<String> sayHello() {
final HttpHeaders httpHeaders= new HttpHeaders();
httpHeaders.setContentType(MediaType.APPLICATION_JSON);
return new ResponseEntity<String>("{\"msg\": \"Hello World\"}", httpHeaders, HttpStatus.OK);
}
}
Build and run:
mvn clean install
mvn jetty:start
Test:
> GET /hello HTTP/1.1
> Host: localhost:8080
> User-Agent: insomnia/5.15.0
> Accept: */*
< HTTP/1.1 200 OK
< Date: Fri, 27 Apr 2018 00:06:07 GMT
< Content-Type: application/json
< Content-Length: 22
< Server: Jetty(9.2.1.v20140609)
Content received:
{
"msg": "Hello World"
}
