Apache CXF helps you build and develop services using frontend programming APIs, like JAX-WS and JAX-RS. These services can speak a variety of protocols such as SOAP, XML/HTTP, RESTful HTTP, or CORBA and work over a variety of transports such as HTTP, JMS or JBI. In this tutorial, I will show you how to use Apache CXF to create a simple RESTful web service.
I am going to use the following tools and technologies.
- Apache CXF 2.2.12
- JDK 1.7
- Tomcat 7.0
- Maven
- Eclipse
I am going to take you to the following areas in this tutorial.
- Service Class and Mapping Configuration
- BootStrap Implimentation
- Front Controller Configuration
- Application Deployment
- Testing
Before start coding let's create a dynamic web project using the following maven command.
1 | mvn archetype:generate -DgroupId=com.techiekernel.rest -DartifactId=JAXRS-CXF -DarchetypeArtifactId=maven-archetype-webapp -DinteractiveMode=false |
After executing, the project will be get created with pom.xml file. As I am using JDK 7 and annotations, I have to specify the updated maven plugin. After giving the CXF dependency, the pom.xml looks as following.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 | <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>com.techiekernel.rest</groupId> <artifactId>JAXRS-CXF</artifactId> <packaging>war</packaging> <version>1.0-SNAPSHOT</version> <name>JAXRS-Jersey Maven Webapp</name> <url>http://maven.apache.org</url> <dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>3.8.1</version> <scope>test</scope> </dependency> <dependency> <groupId>org.apache.cxf</groupId> <artifactId>cxf-rt-frontend-jaxrs</artifactId> <version>2.2.12</version> <type>jar</type> <scope>compile</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-war-plugin</artifactId> <version>2.1.1</version> </plugin> <plugin> <artifactId>maven-compiler-plugin</artifactId> <configuration> <source>1.5</source> <target>1.5</target> </configuration> </plugin> </plugins> <finalName>JAXRS-CXF</finalName> </build> </project> |
Service Class and Mapping Configuration:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | package com.techiekernel.rest; import javax.ws.rs.GET; import javax.ws.rs.Path; import javax.ws.rs.PathParam; import javax.ws.rs.core.Response; @Path("/foobar") public class FooBarService { @GET @Path("/{param}") public Response getMsg(@PathParam("param") String msg) { String output = "FooBar say : " + msg; return Response.status(200).entity(output).build(); } } |
Front Controller Configuration:
As we are not using any framework like spring we have to write our own implimentation to make the service available. We are going to achieve this giving a implimentation to "javax.ws.rs.core.Application".
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 | package com.techiekernel.rest; import java.util.Collections; import java.util.HashSet; import java.util.Set; import javax.ws.rs.core.Application; import javax.ws.rs.ext.Provider; @Provider public class CXFApplication extends Application { private Set<Object> singletons = new HashSet<Object>(); public CXFApplication() { singletons.add(new FooBarService()); } @Override public Set<Object> getSingletons() { return singletons; } @Override public Set<Class<?>> getClasses() { // TODO Auto-generated method stub return Collections.emptySet(); } } |
Front Controller Configuration:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 | <web-app id="WebApp_ID" version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"> <display-name>JAXRS-CXF</display-name> <servlet> <servlet-name>CXFApplication</servlet-name> <display-name>CXFApplication</display-name> <servlet-class> org.apache.cxf.jaxrs.servlet.CXFNonSpringJaxrsServlet </servlet-class> <init-param> <param-name>javax.ws.rs.Application</param-name> <param-value>com.techiekernel.rest.CXFApplication</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>CXFApplication</servlet-name> <url-pattern>/ws/*</url-pattern> </servlet-mapping> </web-app> |
Application Deployment:
Now every thing is ready and time to build for creating a war file.
1 | mvn clean install; |
On successful completion of the above command a war file will be get created in target folder. Copy the war file to webapp folder of your tomcat and start the tomcat.
Testing:
Once tomcat is started use the following url to access the web service.
1 | http://localhost:8080/JAXRS-CXF/ws/foobar/foobar |
Output:
Once you hit the url in the browser, you are going to get the following output.
1 | FooBar say : foobar |
Source Code:
You can pull the code from GitHub.
