Java で REST API (Post) 実行

ネットの記事をいろいろ参考にしながら、Java 1.8 の標準 API だけで作ってみた。

import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;
import java.nio.charset.StandardCharsets;

public class MainPost {

    public static void main(String[] args) {
        String urlStr = "https://httpbin.org/post";
        HttpURLConnection urlConn = null;
        BufferedReader reader = null;
        try {
            URL url = new URL(urlStr);
            urlConn = (HttpURLConnection)url.openConnection();

            // Post 送信
            urlConn.setRequestMethod("POST");
            urlConn.setDoOutput(true);
            OutputStream out = urlConn.getOutputStream();
            OutputStreamWriter writer = new OutputStreamWriter(out, StandardCharsets.UTF_8);
            String postData = "param1=value1&param2=value2";
            writer.write(postData);
            writer.close();

            // Post の response を受信
            int status = urlConn.getResponseCode();
            System.out.println("HTTP Status:" + status);
            if (status == HttpURLConnection.HTTP_OK) {
                InputStream in = urlConn.getInputStream();
                reader = new BufferedReader(new InputStreamReader(in, StandardCharsets.UTF_8));
                StringBuilder res = new StringBuilder();
                String line;
                while ((line = reader.readLine()) != null) {
                    res.append(line).append(System.lineSeparator());
                }
                System.out.println(res);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (reader != null) {
                    reader.close();
                }
                if (urlConn != null) {
                    urlConn.disconnect();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}