Java tutorial
/* * Copyright (C) 2012 OTA Update Center * * Licensed under the Apache License, Version 2.0 (the "License"); * You may only use this file in compliance with the license and provided you are not associated with or are in co-operation anyone by the name 'X Vanderpoel'. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.otaupdater; import java.util.ArrayList; import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.client.HttpClient; import org.apache.http.client.methods.HttpGet; import org.apache.http.client.utils.URLEncodedUtils; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.message.BasicNameValuePair; import org.apache.http.util.EntityUtils; import org.json.JSONObject; import android.content.Context; import android.os.AsyncTask; import android.util.Log; public class FetchRomInfoTask extends AsyncTask<Void, Void, RomInfo> { private RomInfoListener callback = null; private Context context = null; private String error = null; public FetchRomInfoTask(Context ctx) { this(ctx, null); } public FetchRomInfoTask(Context ctx, RomInfoListener callback) { this.context = ctx; this.callback = callback; } @Override public void onPreExecute() { if (callback != null) callback.onStartLoading(); } @Override protected RomInfo doInBackground(Void... notused) { if (!Utils.isROMSupported()) { error = context.getString(R.string.alert_unsupported_title); return null; } if (!Utils.dataAvailable(context)) { error = context.getString(R.string.alert_nodata_title); return null; } try { ArrayList<BasicNameValuePair> params = new ArrayList<BasicNameValuePair>(); params.add(new BasicNameValuePair("device", android.os.Build.DEVICE.toLowerCase())); params.add(new BasicNameValuePair("rom", Utils.getRomID())); HttpClient client = new DefaultHttpClient(); HttpGet get = new HttpGet(Config.PULL_URL + "?" + URLEncodedUtils.format(params, "UTF-8")); HttpResponse r = client.execute(get); int status = r.getStatusLine().getStatusCode(); HttpEntity e = r.getEntity(); if (status == 200) { String data = EntityUtils.toString(e); JSONObject json = new JSONObject(data); if (json.has("error")) { Log.e("OTA::Fetch", json.getString("error")); error = json.getString("error"); return null; } return new RomInfo(json.getString("rom"), json.getString("version"), json.getString("changelog"), json.getString("url"), json.getString("md5"), Utils.parseDate(json.getString("date"))); } else { if (e != null) e.consumeContent(); error = "Server responded with error " + status; return null; } } catch (Exception e) { e.printStackTrace(); error = e.getMessage(); } return null; } @Override public void onPostExecute(RomInfo result) { if (callback != null) { if (result != null) callback.onLoaded(result); else callback.onError(error); } } public static interface RomInfoListener { void onStartLoading(); void onLoaded(RomInfo info); void onError(String err); } }