How to access Restful web service using Java Http Client

Step-1

First we need to add these dependencies in pom.xml

<!-- GSON -->

<dependency>

<groupId>com.google.code.gson</groupId>

<artifactId>gson</artifactId>

<version>2.3.1</version>

</dependency>

<!-- http client -->

<dependency>

<groupId>org.apache.httpcomponents</groupId>

<artifactId>httpclient</artifactId>

<version>4.1.1</version>

</dependency>

class ProgramService {

     @Override

public void addProgram(ProgramVO programVo) {

DefaultHttpClient client = new DefaultHttpClient();

//This code converting Java Object into JSON String

String json = new GsonBuilder().create().toJson(programVo, ProgramVO.class);

HttpResponse response =null;

try{

      //Define a postRequest request

        HttpPost postRequest = new HttpPost("http://www.gpsprogramys.co.in/com.gps.quiz/android/v1/program/padd");

         

        //Set the API media type in http content-type header

         //Here we are setting content-type & Accept as JSON

        postRequest.setHeader("content-type", "application/json");

        postRequest.setHeader("Accept", "application/json"); 

       

        //Set the request post body

        postRequest.setEntity(new StringEntity(json));

         

        //Send the request; It will immediately return the response in HttpResponse object if any

        response = client.execute(postRequest);

        System.out.println(response.toString());

       

        //verify the valid error code first

        int statusCode = response.getStatusLine().getStatusCode();

       

        System.out.println(statusCode);

        System.out.println(statusCode);

         /*if (statusCode != 201)

        {

            throw new RuntimeException("Failed with HTTP error code : " + statusCode);

        }*/

}

catch (UnsupportedEncodingException e) {

        e.printStackTrace();

    } catch (ClientProtocolException e) {

        e.printStackTrace();

    } catch (IOException e) {

        e.printStackTrace();

    }

finally

    {

        //Important: Close the connect

        client.getConnectionManager().shutdown();

    }

}

}

Rest Provider code :-

@Controller
@Scope("request")
@RequestMapping(value = "/v1/program")
public class ProgramController {

@Autowired
@Qualifier("ProgramService")
private IProgramService iProgramService;

public ProgramController() {
}

@RequestMapping(value =ProgramURIConstant.GET_PROGRAM, method = RequestMethod.GET, produces = { MediaType.APPLICATION_JSON_VALUE })
public @ResponseBody
ProgramVO findProgramById(@PathVariable("pid") String programid) {
ProgramVO result = iProgramService.findProgramByQId(programid);
return result;
}

@RequestMapping(value = ProgramURIConstant.ADD_PROGRAM, method = RequestMethod.POST, produces = { MediaType.APPLICATION_JSON_VALUE })
public @ResponseBody
String addProgram(@RequestBody ProgramVO programVO) {
programVO.setTimestamp(DateUtils.getCurrentTimeIntoTimestamp());
String result = iProgramService.addProgram(programVO);
return result;
}

@RequestMapping(value = "padd", method = RequestMethod.POST)
@ResponseStatus(value=HttpStatus.OK)
public @ResponseBody
String addProgramText(@RequestBody ProgramVO programVO) {
programVO.setTimestamp(DateUtils.getCurrentTimeIntoTimestamp());
String result = iProgramService.addProgram(programVO);
return result;

}
}