samples/MySampleRss/src/com/example/codelab/rssexample/RssService.java - platform/development - Git at Google

 /*
  * Copyright (C) 2007 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * 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.example.codelab.rssexample;

 import android.app.Notification;
 import android.app.NotificationManager;
 import android.app.Service;
 import android.content.Intent;
 import android.content.SharedPreferences;
 import android.os.Binder;
 import android.os.IBinder;
 import android.os.Parcel;
 import android.os.Bundle;
 import android.database.Cursor;
 import android.content.ContentResolver;
 import android.os.Handler;
 import android.text.TextUtils;
 import java.io.BufferedReader;
 import java.net.URL;
 import java.net.MalformedURLException;
 import java.lang.StringBuilder;
 import java.io.InputStreamReader;
 import java.io.IOException;
 import java.util.GregorianCalendar;
 import java.text.SimpleDateFormat;
 import java.util.logging.Logger;
 import java.util.regex.Pattern;
 import java.util.regex.Matcher;
 import java.text.ParseException;

 public class RssService extends Service implements Runnable{
     private Logger mLogger = Logger.getLogger(this.getPackageName());
     public static final String REQUERY_KEY = "Requery_All"; // Sent to tell us force a requery.
     public static final String RSS_URL = "RSS_URL"; // Sent to tell us to requery a specific item.
     private NotificationManager mNM;
     private Cursor mCur;                        // RSS content provider cursor.
     private GregorianCalendar mLastCheckedTime; // Time we last checked our feeds.
     private final String LAST_CHECKED_PREFERENCE = "last_checked";
     static final int UPDATE_FREQUENCY_IN_MINUTES = 60;
     private Handler mHandler;           // Handler to trap our update reminders.
     private final int NOTIFY_ID = 1;    // Identifies our service icon in the icon tray.

     @Override
     protected void onCreate(){
         // Display an icon to show that the service is running.
         mNM = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
         Intent clickIntent = new Intent(Intent.ACTION_MAIN);
         clickIntent.setClassName(MyRssReader5.class.getName());
         Notification note = new Notification(this, R.drawable.rss_icon, "RSS Service",
                 clickIntent, null);
         mNM.notify(NOTIFY_ID, note);
         mHandler = new Handler();

         // Create the intent that will be launched if the user clicks the
         // icon on the status bar. This will launch our RSS Reader app.
         Intent intent = new Intent(MyRssReader.class);

         // Get a cursor over the RSS items.
         ContentResolver rslv = getContentResolver();
         mCur = rslv.query(RssContentProvider.CONTENT_URI, null, null, null, null);

         // Load last updated value.
         // We store last updated value in preferences.
         SharedPreferences pref = getSharedPreferences("", 0);
         mLastCheckedTime = new GregorianCalendar();
         mLastCheckedTime.setTimeInMillis(pref.getLong(LAST_CHECKED_PREFERENCE, 0));

 //BEGIN_INCLUDE(5_1)
         // Need to run ourselves on a new thread, because
         // we will be making resource-intensive HTTP calls.
         // Our run() method will check whether we need to requery
         // our sources.
         Thread thr = new Thread(null, this, "rss_service_thread");
         thr.start();
 //END_INCLUDE(5_1)
         mLogger.info("RssService created");
     }

 //BEGIN_INCLUDE(5_3)
     // A cheap way to pass a message to tell the service to requery.
     @Override
     protected void onStart(Intent intent, int startId){
         super.onStart(startId, arguments);
         Bundle arguments = intent.getExtras();
         if(arguments != null) {
             if(arguments.containsKey(REQUERY_KEY)) {
                 queryRssItems();
             }
             if(arguments.containsKey(RSS_URL)) {
                 // Typically called after adding a new RSS feed to the list.
                 queryItem(arguments.getString(RSS_URL));
             }
         }
     }
 //END_INCLUDE(5_3)

     // When the service is destroyed, get rid of our persistent icon.
     @Override
     protected void onDestroy(){
       mNM.cancel(NOTIFY_ID);
     }

     // Determines whether the next scheduled check time has passed.
     // Loads this value from a stored preference. If it has (or if no
     // previous value has been stored), it will requery all RSS feeds;
     // otherwise, it will post a delayed reminder to check again after
     // now - next_check_time milliseconds.
     public void queryIfPeriodicRefreshRequired() {
         GregorianCalendar nextCheckTime = new GregorianCalendar();
         nextCheckTime = (GregorianCalendar) mLastCheckedTime.clone();
         nextCheckTime.add(GregorianCalendar.MINUTE, UPDATE_FREQUENCY_IN_MINUTES);
         mLogger.info("last checked time:" + mLastCheckedTime.toString() + "  Next checked time: " + nextCheckTime.toString());

         if(mLastCheckedTime.before(nextCheckTime)) {
             queryRssItems();
         } else {
             // Post a message to query again when we get to the next check time.
             long timeTillNextUpdate = mLastCheckedTime.getTimeInMillis() - GregorianCalendar.getInstance().getTimeInMillis();
             mHandler.postDelayed(this, 1000 * 60 * UPDATE_FREQUENCY_IN_MINUTES);
         }

     }

     // Query all feeds. If the new feed has a newer pubDate than the previous,
     // then update it.
     void queryRssItems(){
         mLogger.info("Querying Rss feeds...");

         // The cursor might have gone stale. Requery to be sure.
         // We need to call next() after a requery to get to the
         // first record.
         mCur.requery();
         while (mCur.next()){
              // Get the URL for the feed from the cursor.
              int urlColumnIndex = mCur.getColumnIndex(RssContentProvider.URL);
              String url = mCur.getString(urlColumnIndex);
              queryItem(url);
         }
         // Reset the global "last checked" time
         mLastCheckedTime.setTimeInMillis(System.currentTimeMillis());

         // Post a message to query again in [update_frequency] minutes
         mHandler.postDelayed(this, 1000 * 60 * UPDATE_FREQUENCY_IN_MINUTES);
     }


     // Query an individual RSS feed. Returns true if successful, false otherwise.
     private boolean queryItem(String url) {
         try {
             URL wrappedUrl = new URL(url);
             String rssFeed = readRss(wrappedUrl);
             mLogger.info("RSS Feed " + url + ":\n " + rssFeed);
             if(TextUtils.isEmpty(rssFeed)) {
                 return false;
             }

             // Parse out the feed update date, and compare to the current version.
             // If feed update time is newer, or zero (if never updated, for new
             // items), then update the content, date, and hasBeenRead fields.
             // lastUpdated = <rss><channel><pubDate>value</pubDate></channel></rss>.
             // If that value doesn't exist, the current date is used.
             GregorianCalendar feedPubDate = parseRssDocPubDate(rssFeed);
             GregorianCalendar lastUpdated = new GregorianCalendar();
             int lastUpdatedColumnIndex = mCur.getColumnIndex(RssContentProvider.LAST_UPDATED);
             lastUpdated.setTimeInMillis(mCur.getLong(lastUpdatedColumnIndex));
             if(lastUpdated.getTimeInMillis() == 0 ||
                 lastUpdated.before(feedPubDate) && !TextUtils.isEmpty(rssFeed)) {
                 // Get column indices.
                 int contentColumnIndex = mCur.getColumnIndex(RssContentProvider.CONTENT);
                 int updatedColumnIndex = mCur.getColumnIndex(RssContentProvider.HAS_BEEN_READ);

                 // Update values.
                 mCur.updateString(contentColumnIndex, rssFeed);
                 mCur.updateLong(lastUpdatedColumnIndex, feedPubDate.getTimeInMillis());
                 mCur.updateInt(updatedColumnIndex, 0);
                 mCur.commitUpdates();
             }
         } catch (MalformedURLException ex) {
               mLogger.warning("Error in queryItem: Bad url");
               return false;
         }
         return true;
     }

  // BEGIN_INCLUDE(5_2)
     // Get the <pubDate> content from a feed and return a
     // GregorianCalendar version of the date.
     // If the element doesn't exist or otherwise can't be
     // found, return a date of 0 to force a refresh.
     private GregorianCalendar parseRssDocPubDate(String xml){
         GregorianCalendar cal = new GregorianCalendar();
         cal.setTimeInMillis(0);
         String patt ="<[\\s]*pubDate[\\s]*>(.+?)</pubDate[\\s]*>";
         Pattern p = Pattern.compile(patt);
         Matcher m = p.matcher(xml);
         try {
             if(m.find()) {
                 mLogger.info("pubDate: " + m.group());
                 SimpleDateFormat pubDate = new SimpleDateFormat();
                 cal.setTime(pubDate.parse(m.group(1)));
             }
        } catch(ParseException ex) {
             mLogger.warning("parseRssDocPubDate couldn't find a <pubDate> tag. Returning default value.");
        }
         return cal;
     }

     // Read the submitted RSS page.
     String readRss(URL url){
       String html = "<html><body><h2>No data</h2></body></html>";
       try {
           mLogger.info("URL is:" + url.toString());
           BufferedReader inStream =
               new BufferedReader(new InputStreamReader(url.openStream()),
                       1024);
           String line;
           StringBuilder rssFeed = new StringBuilder();
           while ((line = inStream.readLine()) != null){
               rssFeed.append(line);
           }
           html = rssFeed.toString();
       } catch(IOException ex) {
           mLogger.warning("Couldn't open an RSS stream");
       }
       return html;
     }
 //END_INCLUDE(5_2)

     // Callback we send to ourself to requery all feeds.
     public void run() {
         queryIfPeriodicRefreshRequired();
     }

     // Required by Service. We won't implement it here, but need to
     // include this basic code.
     @Override
     public IBinder onBind(Intent intent){
         return mBinder;
     }

     // This is the object that receives RPC calls from clients.See
     // RemoteService for a more complete example.
     private final IBinder mBinder = new Binder()  {
         @Override
         protected boolean onTransact(int code, Parcel data, Parcel reply, int flags) {
             return super.onTransact(code, data, reply, flags);
         }
     };
 }
	/*
	* Copyright (C) 2007 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* 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.example.codelab.rssexample;

	import android.app.Notification;
	import android.app.NotificationManager;
	import android.app.Service;
	import android.content.Intent;
	import android.content.SharedPreferences;
	import android.os.Binder;
	import android.os.IBinder;
	import android.os.Parcel;
	import android.os.Bundle;
	import android.database.Cursor;
	import android.content.ContentResolver;
	import android.os.Handler;
	import android.text.TextUtils;
	import java.io.BufferedReader;
	import java.net.URL;
	import java.net.MalformedURLException;
	import java.lang.StringBuilder;
	import java.io.InputStreamReader;
	import java.io.IOException;
	import java.util.GregorianCalendar;
	import java.text.SimpleDateFormat;
	import java.util.logging.Logger;
	import java.util.regex.Pattern;
	import java.util.regex.Matcher;
	import java.text.ParseException;

	public class RssService extends Service implements Runnable{
	private Logger mLogger = Logger.getLogger(this.getPackageName());
	public static final String REQUERY_KEY = "Requery_All"; // Sent to tell us force a requery.
	public static final String RSS_URL = "RSS_URL"; // Sent to tell us to requery a specific item.
	private NotificationManager mNM;
	private Cursor mCur; // RSS content provider cursor.
	private GregorianCalendar mLastCheckedTime; // Time we last checked our feeds.
	private final String LAST_CHECKED_PREFERENCE = "last_checked";
	static final int UPDATE_FREQUENCY_IN_MINUTES = 60;
	private Handler mHandler; // Handler to trap our update reminders.
	private final int NOTIFY_ID = 1; // Identifies our service icon in the icon tray.

	@Override
	protected void onCreate(){
	// Display an icon to show that the service is running.
	mNM = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
	Intent clickIntent = new Intent(Intent.ACTION_MAIN);
	clickIntent.setClassName(MyRssReader5.class.getName());
	Notification note = new Notification(this, R.drawable.rss_icon, "RSS Service",
	clickIntent, null);
	mNM.notify(NOTIFY_ID, note);
	mHandler = new Handler();

	// Create the intent that will be launched if the user clicks the
	// icon on the status bar. This will launch our RSS Reader app.
	Intent intent = new Intent(MyRssReader.class);

	// Get a cursor over the RSS items.
	ContentResolver rslv = getContentResolver();
	mCur = rslv.query(RssContentProvider.CONTENT_URI, null, null, null, null);

	// Load last updated value.
	// We store last updated value in preferences.
	SharedPreferences pref = getSharedPreferences("", 0);
	mLastCheckedTime = new GregorianCalendar();
	mLastCheckedTime.setTimeInMillis(pref.getLong(LAST_CHECKED_PREFERENCE, 0));

	//BEGIN_INCLUDE(5_1)
	// Need to run ourselves on a new thread, because
	// we will be making resource-intensive HTTP calls.
	// Our run() method will check whether we need to requery
	// our sources.
	Thread thr = new Thread(null, this, "rss_service_thread");
	thr.start();
	//END_INCLUDE(5_1)
	mLogger.info("RssService created");
	}

	//BEGIN_INCLUDE(5_3)
	// A cheap way to pass a message to tell the service to requery.
	@Override
	protected void onStart(Intent intent, int startId){
	super.onStart(startId, arguments);
	Bundle arguments = intent.getExtras();
	if(arguments != null) {
	if(arguments.containsKey(REQUERY_KEY)) {
	queryRssItems();
	}
	if(arguments.containsKey(RSS_URL)) {
	// Typically called after adding a new RSS feed to the list.
	queryItem(arguments.getString(RSS_URL));
	}
	}
	}
	//END_INCLUDE(5_3)

	// When the service is destroyed, get rid of our persistent icon.
	@Override
	protected void onDestroy(){
	mNM.cancel(NOTIFY_ID);
	}

	// Determines whether the next scheduled check time has passed.
	// Loads this value from a stored preference. If it has (or if no
	// previous value has been stored), it will requery all RSS feeds;
	// otherwise, it will post a delayed reminder to check again after
	// now - next_check_time milliseconds.
	public void queryIfPeriodicRefreshRequired() {
	GregorianCalendar nextCheckTime = new GregorianCalendar();
	nextCheckTime = (GregorianCalendar) mLastCheckedTime.clone();
	nextCheckTime.add(GregorianCalendar.MINUTE, UPDATE_FREQUENCY_IN_MINUTES);
	mLogger.info("last checked time:" + mLastCheckedTime.toString() + " Next checked time: " + nextCheckTime.toString());

	if(mLastCheckedTime.before(nextCheckTime)) {
	queryRssItems();
	} else {
	// Post a message to query again when we get to the next check time.
	long timeTillNextUpdate = mLastCheckedTime.getTimeInMillis() - GregorianCalendar.getInstance().getTimeInMillis();
	mHandler.postDelayed(this, 1000 * 60 * UPDATE_FREQUENCY_IN_MINUTES);
	}

	}

	// Query all feeds. If the new feed has a newer pubDate than the previous,
	// then update it.
	void queryRssItems(){
	mLogger.info("Querying Rss feeds...");

	// The cursor might have gone stale. Requery to be sure.
	// We need to call next() after a requery to get to the
	// first record.
	mCur.requery();
	while (mCur.next()){
	// Get the URL for the feed from the cursor.
	int urlColumnIndex = mCur.getColumnIndex(RssContentProvider.URL);
	String url = mCur.getString(urlColumnIndex);
	queryItem(url);
	}
	// Reset the global "last checked" time
	mLastCheckedTime.setTimeInMillis(System.currentTimeMillis());

	// Post a message to query again in [update_frequency] minutes
	mHandler.postDelayed(this, 1000 * 60 * UPDATE_FREQUENCY_IN_MINUTES);
	}


	// Query an individual RSS feed. Returns true if successful, false otherwise.
	private boolean queryItem(String url) {
	try {
	URL wrappedUrl = new URL(url);
	String rssFeed = readRss(wrappedUrl);
	mLogger.info("RSS Feed " + url + ":\n " + rssFeed);
	if(TextUtils.isEmpty(rssFeed)) {
	return false;
	}

	// Parse out the feed update date, and compare to the current version.
	// If feed update time is newer, or zero (if never updated, for new
	// items), then update the content, date, and hasBeenRead fields.
	// lastUpdated = <rss><channel><pubDate>value</pubDate></channel></rss>.
	// If that value doesn't exist, the current date is used.
	GregorianCalendar feedPubDate = parseRssDocPubDate(rssFeed);
	GregorianCalendar lastUpdated = new GregorianCalendar();
	int lastUpdatedColumnIndex = mCur.getColumnIndex(RssContentProvider.LAST_UPDATED);
	lastUpdated.setTimeInMillis(mCur.getLong(lastUpdatedColumnIndex));
	if(lastUpdated.getTimeInMillis() == 0 \|\|
	lastUpdated.before(feedPubDate) && !TextUtils.isEmpty(rssFeed)) {
	// Get column indices.
	int contentColumnIndex = mCur.getColumnIndex(RssContentProvider.CONTENT);
	int updatedColumnIndex = mCur.getColumnIndex(RssContentProvider.HAS_BEEN_READ);

	// Update values.
	mCur.updateString(contentColumnIndex, rssFeed);
	mCur.updateLong(lastUpdatedColumnIndex, feedPubDate.getTimeInMillis());
	mCur.updateInt(updatedColumnIndex, 0);
	mCur.commitUpdates();
	}
	} catch (MalformedURLException ex) {
	mLogger.warning("Error in queryItem: Bad url");
	return false;
	}
	return true;
	}

	// BEGIN_INCLUDE(5_2)
	// Get the <pubDate> content from a feed and return a
	// GregorianCalendar version of the date.
	// If the element doesn't exist or otherwise can't be
	// found, return a date of 0 to force a refresh.
	private GregorianCalendar parseRssDocPubDate(String xml){
	GregorianCalendar cal = new GregorianCalendar();
	cal.setTimeInMillis(0);
	String patt ="<[\\s]pubDate[\\s]>(.+?)</pubDate[\\s]*>";
	Pattern p = Pattern.compile(patt);
	Matcher m = p.matcher(xml);
	try {
	if(m.find()) {
	mLogger.info("pubDate: " + m.group());
	SimpleDateFormat pubDate = new SimpleDateFormat();
	cal.setTime(pubDate.parse(m.group(1)));
	}
	} catch(ParseException ex) {
	mLogger.warning("parseRssDocPubDate couldn't find a <pubDate> tag. Returning default value.");
	}
	return cal;
	}

	// Read the submitted RSS page.
	String readRss(URL url){
	String html = "<html><body><h2>No data</h2></body></html>";
	try {
	mLogger.info("URL is:" + url.toString());
	BufferedReader inStream =
	new BufferedReader(new InputStreamReader(url.openStream()),
	1024);
	String line;
	StringBuilder rssFeed = new StringBuilder();
	while ((line = inStream.readLine()) != null){
	rssFeed.append(line);
	}
	html = rssFeed.toString();
	} catch(IOException ex) {
	mLogger.warning("Couldn't open an RSS stream");
	}
	return html;
	}
	//END_INCLUDE(5_2)

	// Callback we send to ourself to requery all feeds.
	public void run() {
	queryIfPeriodicRefreshRequired();
	}

	// Required by Service. We won't implement it here, but need to
	// include this basic code.
	@Override
	public IBinder onBind(Intent intent){
	return mBinder;
	}

	// This is the object that receives RPC calls from clients.See
	// RemoteService for a more complete example.
	private final IBinder mBinder = new Binder() {
	@Override
	protected boolean onTransact(int code, Parcel data, Parcel reply, int flags) {
	return super.onTransact(code, data, reply, flags);
	}
	};
	}