Skip to main content

Guide : Spring Boot with Apache CXF for REST services

In this series of guide, we are going to explore writing REST services with Apache CXF using Spring Boot.
The project is build using maven. I assume that you already know how to use maven.
Step 1 : Adding dependencies for Spring Boot
By default you have to inherit the parent pom of spring boot, but that cannot be followed everytime, so I use an alternative to that. I basically add spring boot pom as dependency so that it brings all the dependencies.
<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    <java.version>1.8</java.version>
    <spring.version>1.4.3.RELEASE</spring.version>
    <cxf.version>3.1.10</cxf.version>
</properties>

<dependencies>
    <dependency>
    <!-- Alternative to inheriting from parent spring pom -->
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-dependencies</artifactId>
        <version>${spring.version}</version>
        <type>pom</type>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <version>${spring.version}</version>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.apache.cxf</groupId>
        <artifactId>cxf-spring-boot-starter-jaxrs</artifactId>
        <version>${cxf.version}</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.jaxrs</groupId>
        <artifactId>jackson-jaxrs-json-provider</artifactId>
        <version>2.8.5</version>
    </dependency>
</dependencies>

Step 2: Package structure of application
We can create some basic packages to have an outline of what code will go where and its basically good idea to have a general outline of the application ready. Following are the packages that we will make for now
  • config
  • dao
  • models
  • rest
  • services
  • utils

Step 3 : Spring Boot Starter class
When writing spring boot, you have to create an Application class or in this case i call it Starter class. This class is main class that is the entry point of your packaged spring boot (more on this later). It looks like as below
package org.blog;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

/**
 * Created by Anand_Rajneesh on 3/23/2017.
 */
@SpringBootApplication
public class Starter {

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

@SpringBootApplication does a bunch of stuff under the hood, it basically tells the Spring to do package scan to identify component classes, configuration classes etc.
Step 4 : Writing CXF Service
In rest package that we created in Step 2, create a new class Ping. This will be basically our health check class which would return 200 ok if everything is ok with the service.
package org.blog.rest;

import org.springframework.stereotype.Service;

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.core.Response;

/**
 * Created by Anand_Rajneesh on 3/24/2017.
 */
@Path("/ping")
@Service
public class Ping {

    @GET
    public Response health(){
        return Response.ok().build();
    }
}
Ping class has two annotations : @Service to register it as Spring component. @Path – to specify the url on which the service will be accessible
Step 6 : Enabling CXF
Create an application.properties file in resources folder. Add below line to it
cxf.jaxrs.component-scan=true
This tells cxf to look for Spring components which might act as JAX-RS resources, providers and other extensions.
That’s it, you have basic REST application set up here.
Now package your jar by running mvn package and then start it.
Use url http://localhost:8080/services/ping and it should give a 200 ok back in response.
What you can do on your own is look at the various JAX-RS annotations, play with status codes and http methods. Create more services and experiment.
More on the cxf servlet path configuration and more features of cxf later..

Comments

Post a Comment

Popular posts from this blog

Enabling CXF goodies in Spring Boot

In this post we are going to add some of the CXF features to our existing app that we developed in  previous post . These features are : ID Logging Jackson Provider for POJO to JSON conversion Swagger 2 documentation Step 1: Configuration class Create a RestServer class in config package as shown below package org . blog . config ; import com.fasterxml.jackson.jaxrs.json.JacksonJsonProvider ; import org.apache.cxf.feature.LoggingFeature ; import org.apache.cxf.jaxrs.swagger.Swagger2Feature ; import org.springframework.context.annotation.Bean ; import org.springframework.context.annotation.Configuration ; /** * Created by Anand_Rajneesh on 3/23/2017. */ @Configuration public class RestServer { @Bean public JacksonJsonProvider jsonProvider (){ return new JacksonJsonProvider (); } @Bean public LoggingFeature loggingFeature (){ return new LoggingFeature (); } @Bean public Swagger2Featur

OOPs simply explained

What is OOPs ? It is Object Oriented Programming. It comprises of Polymorphism Encapsulation Inheritance Abstraction Already lost me ? Now here it is read about OOPs as if you deal with it every day. Let's take at OOPs from a Corporate world point of view. There is an organization which comprises of several employees which form a hierarchy. Now every employee has their way of working, some work hard, some like to delegate and some are smart. Though everyone does work in office, they do it in their own way. This is Polymorphism (implementing a function differently while keeping the semantics of function same). Employees are after all humans, we all have secrets. We have our own perspective which we may or may not share with everyone i.e. we have state and behavior only accessible to us. We share some of our secrets with our closest friends, some of our perspective to a group of people depending upon our status. In the end we do keep everything close and private, nothing