Android/HttpRequest通信/HttpURLConnection

準備

AndroidManifest.xml

<uses-permission android:name="android.permission.INTERNET" />

サンプル

同期処理のみ(AsyncTaskなどで実行すること)

CustomHttpURLConnection http = new CustomHttpURLConnection();
http.execGet("https://api.github.com/feeds");

CustomHttpURLConnection.java

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.SocketTimeoutException;
import java.net.URL;
import android.util.Log;

class CustomHttpURLConnection
{
    public void execGet(String strGetUrl) {
        // System.setProperty("http.agent", "Dalvik/2.1.0 (Linux; U; Android 9; H8216 Build/PDP-PKQ1.180708.001-10229)"); // System.getProperty("http.agent");
        Log.i("HttpURLConnection", "ua=" + System.getProperty("http.agent"));
        HttpURLConnection urlConn = null;
        InputStream in = null;
        BufferedReader reader = null;
        try {
            URL url = new URL(strGetUrl);
            urlConn = (HttpURLConnection) url.openConnection();
            urlConn.addRequestProperty("Content-Type", "application/json; charset=UTF-8");
            urlConn.setRequestMethod("GET");
//      urlConn.setRequestMethod("POST");
            urlConn.setConnectTimeout(10000); // 10s
            urlConn.setReadTimeout(1000); // 1s
            urlConn.connect();
            int status = urlConn.getResponseCode();
            Log.i("HttpURLConnection", "status_code=" + status);
            if (status == HttpURLConnection.HTTP_OK) {
                in = urlConn.getInputStream();
                reader = new BufferedReader(new InputStreamReader(in));
                StringBuilder output = new StringBuilder();
                String line;
                while ((line = reader.readLine()) != null) {
                    output.append(line);
                }
                Log.i("HttpURLConnection", "res=" + output.toString());
            }
        } catch (SocketTimeoutException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (reader != null) {
                    reader.close();
                }
                if (urlConn != null) {
                    urlConn.disconnect();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

uaはサーバに接続して変更設定されていることを確認済み。

ドメイン接続許可しないエラーが出るときはこちらを確認

android/開発環境/Android8 [ｼｮｰﾄｶｯﾄ]

参考

https://itsakura.com/java-httpurlconnection

http://d.hatena.ne.jp/Kazuhira/20131026/1382796711

uaを設定しない場合とwebviewからもてっくる場合

HttpURLConnectionのuaデフォ(System.getProperty("http.agent");)

Dalvik/2.1.0 (Linux; U; Android 9; Pixel 2 XL Build/PPR2.181005.003)

webviewのua android/webview/useragent [ｼｮｰﾄｶｯﾄ]

Mozilla/5.0 (Linux; Android 9; Pixel 2 XL Build/PPR2.181005.003; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/70.0.3538.110 Mobile Safari/537.36

retry処理

本来のget処理をexecGetCore()に入れる

    public boolean execGet() throws Exception {
        Exception tmpException = null;
        for (int retry = 0; retry <= mRetry; retry++) {
            try {
                boolean ret = execGetCore();
                if (ret) {
                    return ret;
                }
            } catch (Exception e) {
                tmpException = e;
            }
        }
        if (Exception != null) {
            throw tmpException;
        }
        return false;
    }

async経由

import android.app.Activity;
import android.content.Context;
import android.content.DialogInterface;
import android.content.DialogInterface.OnCancelListener;
import android.os.AsyncTask;
import android.util.Log;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
/*
HttpAsyncTask task = new HttpAsyncTask();
task.setParam1("hoge");
*/
public class HttpAsyncTask extends AsyncTask<String, Integer, Long>
        implements OnCancelListener {
    private final String TAG = "MyAsyncTask";
    private Context mContext;
    private Activity mActivity;
    private String param1;
    public HttpAsyncTask(Context context) {
        this.mContext = context;
    }
    public void setActivity(Activity activity) {
        mActivity = activity;
    }
    public void setParam1(String str) {
        this.param1 = str;
    }
    @Override
    protected void onPreExecute() {
        Log.d(TAG, "onPreExecute");
    }
    @Override
    protected Long doInBackground(String... urls) {
        CustomHttpURLConnection http = new CustomHttpURLConnection();
        try {
            String encode = URLEncoder.encode(param1, "UTF-8");
            String url = "ttps://hoge.example.com/hoge?param1=" + encode;
            http.execGet(url);
            Log.d(TAG, url);
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return 123L;
    }
    @Override
    protected void onProgressUpdate(Integer... values) {
        Log.d(TAG, "onProgressUpdate=" + values[0]);
    }
    @Override
    protected void onCancelled() {
        Log.d(TAG, "onCancelled");
    }
    @Override
    protected void onPostExecute(Long result) {
        Log.d(TAG, "onPostExecute=" + result);
    }
    public void onCancel(DialogInterface dialog) {
        Log.d(TAG, "Dialog onCancell... calling cancel(true)");
        this.cancel(true);
    }
}