Develop a simple RESTful Webservices using Apache CXF and Spring Framework – Part I

This article shows how to create a simple RESTful webservices using Apache CXF which supports JAX-RS.

Part I – A simple RESTful Webservices using Apache CXF
Part II – Testing using RestTemplate and JUNIT
Part III – Exception/Error handling using ExceptionMapper
Part IV – BeanParam Example

Apache CXF supports JAX-WS and JAX-RS APIs. It also provides seamless integration with Spring framework.

Service Definition Interface (ExampleService.java)

package com.idodevjobs.sample.service;

import com.idodevjobs.sample.model.ExampleModel;

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;

@Path("/example")
@Produces("application/json")
public interface ExampleService {

    @GET
    @Path("/{id}")
    public ExampleModel get(@PathParam("id") String id);

}

Service Implementation (ExampleServiceImpl.java)

package com.idodevjobs.sample.service;

import com.idodevjobs.sample.model.ExampleModel;
import org.springframework.stereotype.Service;

@Service("exampleService")
public class ExampleServiceImpl implements ExampleService {

    @Override
    public ExampleModel get(String modelId) {
        return new ExampleModel("example", 1001);
    }
}

Model Object(ExampleModel.java)

package com.idodevjobs.sample.model;

public class ExampleModel {
    private String string;
    private int anInt;

    public ExampleModel() {}

    public ExampleModel(String string, int anInt) {
        this.string = string;
        this.anInt = anInt;
    }

    public String getString() {
        return string;
    }

    public void setString(String string) {
        this.string = string;
    }

    public int getAnInt() {
        return anInt;
    }

    public void setAnInt(int anInt) {
        this.anInt = anInt;
    }

    @Override
    public String toString() {
        return "ExampleModel{" +
                "string='" + string + '\'' +
                ", anInt=" + anInt +
                '}';
    }
}

Web application configuration(web.xml)

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" 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_2_5.xsd">

    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/spring-cxf-rest-example.xml</param-value>
    </context-param>

    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

    <servlet>
        <servlet-name>CXFServlet</servlet-name>
        <servlet-class>
            org.apache.cxf.transport.servlet.CXFServlet
        </servlet-class>
        <load-on-startup>1</load-on-startup>
    </servlet>

    <servlet-mapping>
        <servlet-name>CXFServlet</servlet-name>
        <url-pattern>/services/*</url-pattern>
    </servlet-mapping>

</web-app>

Spring/CXF Configuration(spring-cxf-rest-example.xml)

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:jaxrs="http://cxf.apache.org/jaxrs"
       xmlns:cxf="http://cxf.apache.org/core"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="
                        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
                        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
                        http://cxf.apache.org/jaxrs http://cxf.apache.org/schemas/jaxrs.xsd
                        http://cxf.apache.org/core http://cxf.apache.org/schemas/core.xsd">

    <context:component-scan base-package="com.idodevjobs" />

    <jaxrs:server id="exampleCxfServer" address="/">
        <jaxrs:serviceBeans>
            <ref bean="exampleService"/>
        </jaxrs:serviceBeans>
        <jaxrs:extensionMappings>
            <entry key="json" value="application/json"/>
        </jaxrs:extensionMappings>
        <jaxrs:features>
            <cxf:logging/>
        </jaxrs:features>
        <jaxrs:providers>
            <bean class="com.fasterxml.jackson.jaxrs.json.JacksonJsonProvider" />
        </jaxrs:providers>
    </jaxrs:server>

</beans>

Maven Dependency 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>spring-cxf-rest-example</groupId>
    <artifactId>spring-cxf-rest-example</artifactId>
    <packaging>war</packaging>

    <version>1.0-SNAPSHOT</version>
    <name>spring-cxf-rest-example</name>

    <properties>
        <spring.version>4.0.0.RELEASE</spring.version>
        <cxf.version>3.0.0</cxf.version>
        <jackson.version>2.0.1</jackson.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.cxf</groupId>
            <artifactId>cxf-rt-frontend-jaxrs</artifactId>
            <version>${cxf.version}</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.jaxrs</groupId>
            <artifactId>jackson-jaxrs-json-provider</artifactId>
            <version>${jackson.version}</version>
        </dependency>
    </dependencies>
    <build>
        <finalName>spring-cxf-rest-example</finalName>
    </build>
</project>

Testing

Do a mvn clean install, copy the war to tomcat/webapps directory and start the server by running startup.sh (non-windows) or startup.bat (windows) file.

Open http://localhost:8080/spring-cxf-rest-example/services/example/1 on a browser or any REST client will give

{"string":"example","anInt":1001}

Leave comment for any queries.

Spring framework related tutorials:

REST Webservices using Apache CXF & Spring framework
Spring Data REST using Java configurations
Spring Data REST using XML configurations
Working with multiple properties files in Spring framework
Spring RestTemplate example
Spring prototype scope example