BackConnect.java

package vit.vithandbook.helperClass;

import android.app.Activity;
import android.content.ContentValues;
import android.content.Context;
import android.content.SharedPreferences;
import android.database.sqlite.SQLiteDatabase;
import android.util.Log;
import android.widget.Toast;

import org.json.JSONArray;
import org.json.JSONObject;

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

public class BackConnect {
    Context context;
    String PREF_KEY = "handbook_prefs";

    public BackConnect(Context context) {
        this.context = context;
    }

    public String getDateTime() {
        SharedPreferences prefs = context.getSharedPreferences(PREF_KEY, context.MODE_PRIVATE);
        String date = prefs.getString("last_sync", null);
        DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
        String dateTime = df.format(new Date());
        prefs.edit().putString("last_sync", dateTime);
        if (date != null)
            return date;
        else
            return dateTime;

    }

    public void getUpdatedData() {
        String jsonReply = null;
        try {
            String dateTime = getDateTime();
            String postData = "timestamp=" + dateTime;
            URL url = new URL("http://handbook-entry.herokuapp.com/api/updates");
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setRequestMethod("POST");
            conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
            conn.setRequestProperty("Content-Length", "" + Integer.toString(postData.getBytes().length));
            conn.setDoOutput(true);
            conn.setDoInput(true);
            DataOutputStream wr = new DataOutputStream(conn.getOutputStream());
            wr.writeBytes(postData);
            wr.flush();
            wr.close();
            final int resposnecode = conn.getResponseCode();
            if (resposnecode != 200) {
                ((Activity) context).runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        Toast.makeText(context, "Error fetching updates error code : " + Integer.toString(resposnecode), Toast.LENGTH_LONG).show();
                    }
                });
                return;
            }
            BufferedReader in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
            String line;
            while ((line = in.readLine()) != null) {
                jsonReply += line;
            }
            Log.d("json", jsonReply);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public void parseJsonData(String jsonData) throws Exception {
        SQLiteDatabase db = context.openOrCreateDatabase("Handbook", context.MODE_PRIVATE, null);
        db.beginTransaction();
        JSONArray array = new JSONArray(jsonData);
        for (int i = 0; i < array.length(); i++) {
            JSONObject obj = array.getJSONObject(i);
            ContentValues cv = getCV(obj);
            db.insertOrThrow("articles", null, cv);
        }
        db.setTransactionSuccessful();
        db.endTransaction();
        db.close();
    }

    ContentValues getCV(JSONObject object) throws Exception {
        ContentValues values = new ContentValues();
        values.put("main_category", object.getString("main_category"));
        values.put("sub_category", object.getString("sub_category"));
        values.put("topic", object.getString("topic"));
        values.put("content", object.getString("content"));
        values.put("tags", object.getString("tags"));
        return values;
    }
}