Spring Restful Web Services Example

Spring frameworks provides the Restful web services implementation, here is one simple example to implement Web services using Spring.

Softwares Used

• Java 1.8
• Spring 4
• Jetty Server

Create a maven project using web-app archetype and add below dependencies

<dependency>
            <groupId>org.eclipse.jetty</groupId>
            <artifactId>jetty-server</artifactId>
            <version>9.2.3.v20140905</version>
        </dependency>
        <dependency>
            <groupId>org.eclipse.jetty</groupId>
            <artifactId>jetty-servlet</artifactId>
            <version>9.2.3.v20140905</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>4.2.4.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.5.0</version>
        </dependency>

Create a Controller class to define our service

package com.vinod.vinod_spring_test;

import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
@RequestMapping("/state")
public class StateController {
    @RequestMapping(value = "/{code}", method = RequestMethod.GET)
    public @ResponseBody String getState(@PathVariable String code) {
        String result;
        if (code.equals("KL")) {
            result = "Kerala";
        } else {
            result = "Default State";
        }
        return result;
    }
}
  

Spring configuration class

package com.vinod.vinod_spring_test;

import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
@Configuration
@ComponentScan(basePackages = {
        "com.vinod.vinod_spring_test"})
public class MyWebServiceSpringConfig{

}

Main class to start Jetty server

package com.vinod.vinod_spring_test;

import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.servlet.ServletContextHandler;
import org.eclipse.jetty.servlet.ServletHolder;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;

public class JettyWebserviceStart {

    public static void main(String[] args) {
        final AnnotationConfigWebApplicationContext applicationContext = new AnnotationConfigWebApplicationContext();
        applicationContext.register(MyWebServiceSpringConfig.class);
        final ServletHolder servletHolder = new ServletHolder(new DispatcherServlet(applicationContext));
        final ServletContextHandler context = new ServletContextHandler();
        context.setContextPath("/");
        context.addServlet(servletHolder, "/*");
        final Server server = new Server(8080);
        server.setHandler(context);
        try {
            server.start();
            server.join();
        } catch (Exception e) {
            server.destroy();
            e.printStackTrace();
        }
    }

}
  

Output

Run the above program and hit the below url
http://localhost:8080/state/KL

Download examples

https://github.com/kkvinodkumaran/spring