Java REST Client

Posted 2020-08-19 Life Overflow

GET:

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

public class GETRestClient {

    private static final String targetURL = "http://localhost:8080/path/get.serv";

    public static void main(String[] args) {

        try {

            URL restServiceURL = new URL(targetURL);

            HttpURLConnection httpConnection = (HttpURLConnection) restServiceURL.openConnection();
            httpConnection.setRequestMethod("GET");
            httpConnection.setRequestProperty("Accept", "application/json");

            if (httpConnection.getResponseCode() != 200) {
                throw new RuntimeException("HTTP GET Request Failed with Error code : "+ httpConnection.getResponseCode());
            }

            BufferedReader responseBuffer = new BufferedReader(
                    new InputStreamReader((httpConnection.getInputStream())));

            String output;
            System.out.println("Output from Server:  \n");

            while ((output = responseBuffer.readLine()) != null) {
                System.out.println(output);
            }
            httpConnection.disconnect();
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }
}

POST:

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

public class POSTRestClient {
    private static final String targetURL = "http://localhost:8080/path/post.serv";

    public static void main(String[] args) {
        try {

            URL targetUrl = new URL(targetURL);

            HttpURLConnection httpConnection = (HttpURLConnection) targetUrl.openConnection();
            httpConnection.setDoOutput(true);
            httpConnection.setRequestMethod("POST");
            httpConnection.setRequestProperty("Content-Type", "application/json");

            String input = "{\"id\":1,\"no\":\"no0003\",\"name\":\"jack\"}";

            OutputStream outputStream = httpConnection.getOutputStream();
            outputStream.write(input.getBytes());
            outputStream.flush();

            if (httpConnection.getResponseCode() != 200) {
                throw new RuntimeException("Failed : HTTP error code : " + httpConnection.getResponseCode());
            }

            BufferedReader responseBuffer = new BufferedReader(
                    new InputStreamReader((httpConnection.getInputStream())));

            String output;
            System.out.println("Output from Server:\n");
            while ((output = responseBuffer.readLine()) != null) {
                System.out.println(output);
            }

            httpConnection.disconnect();
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }
}