CXF Restful Tutorial
CXF Restful Tutorial explains step by step details of Creating / Developing Java rest Web services using Apache CXF, Spring and Eclipse
JAX-RS is Java API for RESTful Webservices which is very rely upon Representational State Transfer model, you can view JAX-RS specification
JAX-RS uses annotations for simplifying the development efforts.
Now a days more & more deployment is going based on restful services compare to WSDL Webservices, due to the weights towards the simplicity of configuration
You can see the below example, which is demonstrating How to create a Restful service using CXF
Required Libraries
You need to download
Following jar must be in classpath
- commons-logging-1.1.1.jar
- cxf-2.7.3.jar
- httpasyncclient-4.0-beta3.jar
- httpclient-4.2.1.jar
- httpcore-4.2.2.jar
- httpcore-nio-4.2.2.jar
- neethi-3.0.2.jar
- spring-aop-3.0.7.RELEASE.jar
- spring-asm-3.0.7.RELEASE.jar
- spring-beans-3.0.7.RELEASE.jar
- spring-context-3.0.7.RELEASE.jar
- spring-core-3.0.7.RELEASE.jar
- spring-expression-3.0.7.RELEASE.jar
- spring-web-3.0.7.RELEASE.jar
- wsdl4j-1.6.2.jar
- jaxb-impl-2.2.6.jar
- javax.ws.rs-api-2.0-m10.jar
- xmlschema-core-2.0.3.jar
- jettison-1.3.3.jar (JSON library)
CXF Restful Tutorial
I am creating a sample restful service project that pass Student object and return with some changes on that object. The service is using simple POJO (Plain Old Java Object) bean.
Firstly create a Dynamic Web Project (File->New->Dynamic Web Project) named "CXFRestfulTutorial" according to following screenshot
Create a Student Object
import javax.xml.bind.annotation.XmlRootElement;
@XmlRootElement(name = "Student")
public class Student {
private String name;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
Here @XmlRootElement(name = "Student"), is a JAXB convension specifies that Student is XML document.
If you are specifies that @Produces("application/json") then Jettison library converts the JAXB to json text as response
Create a Service Interface
This service interface will defines which methods of restful service, to be invoked by the client
public interface ChangeStudentDetails {
Student changeName(Student student);
Student getName();
}
Implement the Service Interface
Here we implment the service interface created on the previous step
Here we are using one example showing with GET method& another with POST method
GET---> Calling this method will not result any changes to the server
POST---> Calling this method will result changes to the server, This have more secure than GET method
import javax.ws.rs.Consumes;
import javax.ws.rs.GET;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
@Consumes("application/json")
@Produces("application/json")
public class ChangeStudentDetailsImpl implements ChangeStudentDetails {
@POST
@Path("/changeName")
public Student changeName(Student student) {
student.setName("HELLO " + student.getName());
return student;
}
@GET
@Path("/getName")
public Student getName() {
Student student = new Student();
student.setName("Rockey");
return student;
}
}
Note; On the above ChangeStudentDetailsImpl class, implementing an interface is not necessity, you can create restful services without implementing an interface.
@Consumes annotation specifies, the request is coming from the client
you can specify the Mime type as @Consumes("application/xml"), if the request is in xml format
@Produces annotation specifies, the response is going to the client
you can specify the Mime type as @Produces ("application/xml"), if the response need to be in xml format
Create a cxf.xml
CXF is using Spring internally, Finding classes by spring we need to add service implementation beans are added on "jaxrs:serviceBeans".
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:jaxrs="http://cxf.apache.org/jaxrs" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://cxf.apache.org/jaxrs http://cxf.apache.org/schemas/jaxrs.xsd"> <import resource="classpath:META-INF/cxf/cxf.xml" /> <jaxrs:server id="base" address="/rest"> <jaxrs:serviceBeans> <ref bean="StudentService" /> </jaxrs:serviceBeans> </jaxrs:server> <bean id="StudentService" class="com.student.ChangeStudentDetailsImpl" /> </beans>
Change web.xml
Change the web.xml file to find CXF servlet and cxf.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/cxf.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>/*</url-pattern> </servlet-mapping> </web-app>
Publishing CXF Restful Service
Deployed REST Web Service Using CXF