Introduction

Following is simple JAX-RS tutorial, which sends “Hello World” text as response string using JAX-RS API and Jersey implementation. Technologies and Tools used in this article:

  1. JDK
  2. Eclipse
  3. Tomcat
  4. Maven
  5. Jersey 1.8

Create Maven Web Project

Create a Maven web project and name it “helloworld” .

  • File -> New -> Other -> Maven Project -> Next
  • Select maven-archetype-webapp
  • Select Next
  • Type Group Id, Artifact Id and Package name
  • And select Finish

Add Project Dependencies

Add Jersey repository using Maven. Use Maven URL to get appropriate repository.

Now update pom.xml file by adding following dependency.

File : pom.xml

  <dependency>
     <groupId>com.sun.jersey</groupId>
     <artifactId>jersey-server</artifactId>
     <version>1.8</version>
  </dependency>

Create REST Service

Now it is time to create a class which serves as REST service. Create class named RestService and a public method getMessage

package com.zain.restapi;

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


@Path("/message")
public class RestService {

 @GET
 public Response getMessage() {

  String message = "Hello World!";

  return Response.status(200).entity(message).type("text/plain").build();
 }
}

Note: @Path annotation act as routing which map incoming URI to appropriate Class Update web.xml for Jersey configuration In web.xml, add servlet with class com.sun.jersey.spi.container.servlet.ServletContainer

File : web.xml

<web-app  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">
      
       <servlet>
              <servlet-name>jersey-serlvet</servlet-name>
              <servlet-class>
                     com.sun.jersey.spi.container.servlet.ServletContainer
                </servlet-class>
              <init-param>
                   <param-name>com.sun.jersey.config.property.packages</param-name>
                   <param-value>com.zain.restapi</param-value>
              </init-param>
              <load-on-startup>1</load-on-startup>
       </servlet>

       <servlet-mapping>
              <servlet-name>jersey-serlvet</servlet-name>
              <url-pattern>/rest/*</url-pattern>
       </servlet-mapping>
</web-app>

Directory Structure

Final project directory structure

jax-rs directory structure

Demo

To execute this application you need to type following URL

http://localhost:8080/{project name}/{jersey servlet name}/{@path param value}

here is actual URL for this tutorial.

http://localhost:8080/helloworld/rest/message

jax-rs directory demo

Source Code

Download source code from this Github

References