In these cases Open Street Map is a good solution. Most of the applications written using google map api use google map data for displaying map. In this cases one should find a solution to integrate OSM inside google map api.

After some RnD on google map api and OSM I found out a solution to this. Google map api has a nice provision to add custom map types. And I used this feature to implement the solution. I added a custom map type in my google map and fetch the desired tiles from osm server. Here is the JavaScript code snippet:

var map = new GMap(document.getElementById(“map”));

map.addControl(new GScaleControl());

map.addControl(new GLargeMapControl());

map.addControl(new GMapTypeControl());

//Custom function for fetchng tiles from OSM server

CustomGetTileUrl=function(a,b){

return ‘http://a.tile.openstreetmap.org/’+b+’/'+a.x+’/'+a.y+’.png’;

}

var copyright = new GCopyright(1,

new GLatLngBounds(new GLatLng(53.8136257,-3.0981445),

new GLatLng(53.8654855,-2.9663944) ),

17, “”);

var copyrightCollection = new GCopyrightCollection(”);

copyrightCollection.addCopyright(copyright);

var tilelayers = [new GTileLayer(copyrightCollection,1,17)];

tilelayers[0].getTileUrl = CustomGetTileUrl;

var osmmap = new GMapType(tilelayers, G_SATELLITE_MAP.getProjection(), “O.S.M.”);

map.addMapType(osmmap);

map.setCenter(new GLatLng(34.6891,33.0182), 14, osmmap);

This will create an extra map type labeled “O. S.M.” besides the standard map types of google map api.

Here is the details:

Server used:
Tomcat 6.0.16 as servlet container x 2
Apache 2.2.6 as load balancer x 1

Testing Tool:

Jakarta JMeter 2.6.1

Apache Configuration:

Here, I created a cluster named mycluster using 2 tomcat server and sticksession named as JSESSIONID. My test application myapp was running on both of the tomcat server.

I used loadfactor 50 on both of the tomcat server (meaning both of them will be sharing equal load). I

1. Enable mod_proxy: In httpd.conf enable/add

LoadModule proxy_module modules/mod_proxy.so

2. Enable mod_proxy_balancer: In httpd.conf

LoadModule proxy_balancer_module modules/mod_proxy_balancer.so

3. Configure the load balancer on the cluster and balancer manager:

In httpd.conf add these lines:

ProxyPass /myapp balancer://mycluster stickysession=JSESSIONID

<Proxy balancer://mycluster>


BalancerMember http://localhost:8080/myapp route=tomcat1 loadfactor=50
BalancerMember http://localhost:3333/myapp route=tomcat2 loadfactor=50

</Proxy>

<Location /balancer-manager>
SetHandler balancer-manager
</Location>

After restarting the server and hitting http://localhost/balancer-manager in a browser it showed me the configurations of the cluster.

Tomcat Configuration:

1. In server.xml file of tomcat running on 8080 port I configured the jvm route as tomcat1 as :

<Engine name="Catalina" defaultHost="localhost" jvmRoute="tomcat1">

By editing the engine tag.

2. In server.xml file of tomcat running on 3333 port I configured the jvm route as tomcat1 the same way:

<Engine name="Catalina" defaultHost="localhost" jvmRoute="tomcat2">

The testing application:

I used a single servlet for the test application myapp.

Here is the code snippet of the servlet named myservlet:

ServletContext sc = this.getServletContext();
String servername = sc.getInitParameter("servername");
out.print("This is from ::" + servername);

In web.xml of the application I added a context parameter named servername which value was server1 while deploying into tomcat1(on port 8080) and server2 on tomcat2(running on 3333 port).

Testing:

With JMeter I created a script for hiitting the url http://localhost/myapp/myservlet using 400 concurrent thread in 20 loops to see the effect.

1. Optimizing MySQL: Queries and Indexes
2. Using Fulltext Indexes in MySQL – Part 1
3. Using Fulltext Indexes in MySQL – Part 2, Boolean searches

name[0] = “sihan”

name[1] = “rasel”

name[2] = “siam”

name[3] = “shamim”

All I have to do build the query string like this :

http://server_url:server_port/servletname?name=sihan&name=rasel&name=siam&name=shamim

And in the servlet we can get the array like this:

String[] names = request.getParameterValues("name");

Then ‘names‘ array will contain all the four values passed in ‘name‘ parameter.

• microedition.media.version :: 1.1
• supports.mixing :: false
• supports.audio.capture :: true
• supports.video.capture :: false
• supports.recording :: true
• audio.encodings :: encoding=audio/amr
• video.encodings :: encoding=video/H263
• video.snapshot.encodings :: encoding=jpeg encoding-png
• streamable.contents :: video.mpeg

And previously I found (source http://developers.sun.com/mobility/apis/articles/mmapioptions/ ):

• microedition.media.version returns a string representing the version of MMAPI implemented, "1.0" or "1.1" if MMAPI is supported, or null if it isn’t.
• supports.mixing returns true if mixing is supported, false if it isn’t.
• supports.audio.capture returns true if audio capture is supported, false if it isn’t.
• supports.video.capture returns true if video capture is supported, false if it isn’t.
• supports.recording returns true if recording is supported, false if it isn’t.
• audio.encodings returns a string representing the supported audio capture formats, or null if audio capture isn’t supported.
• video.encodings returns a string representing the supported video capture formats, or null if video capture isn’t supported.
• video.snapshot.encodings returns a string representing the supported image capture formats, or null if video snapshot isn’t supported.
• streamable.contents returns a string representing the supported streamable content types, in MIME syntax.

Now have a look at my benchmark result:

1. it shows “supports.video.capture” as “false” meaning that it does not support video capture but shows “encoding=video/H263” as "video.encodings", representing the supported video capture format as video/H263. Also it shows “video.snapshot.encodings” as “encoding=jpeg encoding-png” which means its supported image capture formats are “jpeg” and “png”. These things are self cotradictory. Ideally video.encodings,video.snapshot.encodings should be null.
   
2. In my benchmark I found “supports.recording“ as “true” meaning that recording is supported. At first glance I was astonished thinking that “this handset does not support video capture but supports recording !(I was thinking of video recording as recording)  “ . After some googling I came to know that

You may encounter some confusion when trying to reconcile some of the property values mentioned above with what you observe on a real device. For example: the Nokia 3230 and the Nokia 6600 both return true for both the supports.video.capture and the supports.recording properties. So it seems that both devices will support video recording. But there is a catch. If supports.recording returns true, you can record media using at least one player type — at least one, but not necessarily all. The Nokia 6600 supports the recording of audio, but not the recording of video. But the Nokia 3230 also supports video recording.

(source : http://www.javaworld.com/javaworld/jw-09-2007/jw-09-mobilevideo1.html?page=2)

The case is the same for Nokia-6600 and Samsung-SGH-U700 handsets.

And running my video/image capturing program I always get “javax.microedition.media.MediaException:Not Support Camera”. Then I became sure that Neither video recording nor snap shot is possible on this device with MMAPI.


<?xml version="1.0" encoding="UTF-8"?>
<rss version="2.0">
<channel>
<generator>NFE/1.0</generator>
<title>Google News - Sci/Tech</title>
<link>http://news.google.com/?ned=us&amp;topic=t</link>
<language>en</language>
<webMaster>news-feedback@google.com</webMaster>
<copyright>&amp;copy;2008 Google</copyright>
<pubDate>Wed, 06 Aug 2008 07:13:30 GMT</pubDate>
<lastBuildDate>Wed, 06 Aug 2008 07:13:30 GMT</lastBuildDate>
<image>
<title>Google News</title>
<url>http://news.google.com/intl/en_us/images/news_res.gif</url>
<link>http://news.google.com/</link>
</image>
<item>
<title>Delta to Offer Wi-Fi on US Flights - New York Times</title>
<link>http://news.google.com/news/url?sa=T&amp;ct=us/0-0&amp;fd=R&amp;url=http://www.nytimes.com/2008/08/06/technology/06delta.html%3Fref%3Dbusiness&amp;cid=1233786045&amp;ei=Gk-ZSLbVI4PGlgS_94jVBA&amp;usg=AFQjCNHnUSPm9sCPP4k2gWPBDboZAiYtCw</link>
<guid isPermaLink="false">tag:news.google.com,2005:cluster=498a14bd
</guid>
<pubDate>Wed, 06 Aug 2008 01:10:42 GMT</pubDate>
<description>&lt;table border=0 width= valign=top cellpadding=2 cellspacing=7&gt;&lt;tr&gt;&lt;td width=80 align=center valign=top&gt;&lt;font style=&quot;font-size:85%;font-family:arial,sans-serif&quot;&gt;&lt;a href=&quot;http://news.google.com/news/url?sa=T&amp;ct=us/0i-0&amp;fd=R&amp;url=http://www.geekzone.co.nz/content.asp%3Fcontentid%3D7864&amp;cid=1233786045&amp;ei=Gk-ZSLbVI4PGlgS_94jVBA&amp;usg=AFQjCNF4sPd1YWYzXRyLVYtIYVl_ndmW4g&quot;&gt; .......
</description>

</item>
<item>
<title>LiMo lands seven new phones - Register</title>
<link>http://news.google.com/news/url?sa=T&amp;ct=us/19-0&amp;fd=R&amp;url=http://www.theregister.co.uk/2008/08/05/limo_lands_seven_new_phones/&amp;cid=1233302260&amp;ei=Gk-ZSLbVI4PGlgS_94jVBA&amp;usg=AFQjCNEILOMvAvv5fwcFWpYLWWJVs7vc5Q</link>
<guid isPermaLink="false">tag:news.google.com,2005:cluster=4982b2f4
</guid>
<pubDate>Tue, 05 Aug 2008 01:00:06 GMT</pubDate>
<description>&lt;table border=0 width= valign=top cellpadding=2 cellspacing=7&gt;&lt;tr&gt;&lt;td width=80 align=center valign=top&gt;&lt;font style=&quot;font-size:85%;limo-platform/&amp;cid=1233302260&amp;ei=Gk-ZSLbVI4PGlgS_94jVBA&amp;usg=AFQjCNHS1CWmT1jipl0N-Q-VEOnxM-TmRg&quot;&gt;&lt;img src=http://news.google.com/news?imgefp=hOtr_7v_dyoJ&amp;....</description>
</item>
</channel>
</rss>

Using PHP’s SimpleXML(introduced in PHP5) api it is very easy to access different nodes of the xml above. Like, if we want to get the title of the rss at google news we can write,

$url = "http://news.google.com/?ned=us&topic=t&output=rss"; // url of google news
$xml = simplexml_load_file($url); //loading the document
$title = $xml->channel->title; //gets the title of the document.


The beauty of the function "simplexml_load_file()" is : it does not only load and parse the document but also points to the root element of the document (which is 'rss' here).

Using ‘Simple XML api’ the following code snippet prints news from google news rss :

<?php
$url = "http://news.google.com/?ned=us&topic=t&output=rss";
$rss = simplexml_load_file($url);
if($rss)
{
echo '<h1>'.$rss->channel->title.'</h1>';
echo '<li>'.$rss->channel->pubDate.'</li>';
$items = $rss->channel->item;
foreach($items as $item)
{
$title = $item->title;
$link = $item->link;
$published_on = $item->pubDate;
$description = $item->description;
echo '<h3><a href="'.$link.'">'.$title.'</a></h3>';
echo '<span>('.$published_on.')</span>';
echo '<p>'.$description.'</p>';
}
}
?>


Set: Nokia-6300

1. Locator string for capturing should be different for capturing image and video

For image it should be,

“capture://image”

For video it should be,

“capture://video”

2. Shows device(camera) unavailable when battery charge is low.

3. png encoding in getSnapShot() method is not supported. Using null as parameter works fine.

Set: Sony Ericsson W850i

1. Problem: Got black screen while capturing more than one time(in canvas).

Solution: Probably caused by paint overwrite problem in this device. Used form display to show camera and it solved the problem.

2. Locator string for capturing is “capture://audio_video” for capturing image and video

3. “png” encoding in getSnapShot() method is not supported. Also custom height, width parameter does not work. Using null as parameter works fine.

4. Video rotates 90 degree counter clockwise after capturing: yet to find a solution.

Note:

1. null in the getSnapShot() method means default parameter of the set which is “encoding=png” and “dimension=480×640″ in case of SE 850i

2. In Other sets of Nokia N series(95,93,90,82,76,73,70) the locator string “capture://video” works fine; also png encoding and custom dimensions works fine.

Here is some important system properties to check while working with MMAPI:

• “microedition.amms.version”
• “microedition.media.version”
• “supports.mixing”
• “supports.audio.capture”
• “supports.video.capture”
• “supports.recording”
• “audio.encodings”
• “video.encodings”
• “video.snapshot.encodings”
• “streamable.contents”

Here is a sample code for such an URLEncoder:

public class URLEncoder {
public static String encode(String s, String enc) throws IOException {
ByteArrayOutputStream bOut = new ByteArrayOutputStream();
DataOutputStream dOut = new DataOutputStream(bOut);
StringBuffer ret = new StringBuffer(); //return value
dOut.writeUTF(s);
ByteArrayInputStream bIn = new ByteArrayInputStream(bOut.toByteArray());
bIn.read();
bIn.read();
int c = bIn.read();
while (c >= 0) {
if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || c == '.' || c == '-' || c == '*' || c == '_') {
ret.append((char) c);
} else if (c == ' ') {
ret.append('+');
} else {
if (c < 128 ) {
appendHex(c, ret);
} else if (c < 224) {
appendHex(c, ret);
appendHex(bIn.read(), ret);
} else if (c < 240) {
appendHex(c, ret);
appendHex(bIn.read(), ret);
appendHex(bIn.read(), ret);
}
}
c = bIn.read();
}
return ret.toString();
}
private static void appendHex(int arg0, StringBuffer buff) {
buff.append('%');
if (arg0 < 16) {
buff.append('0');
}
buff.append(Integer.toHexString(arg0));
}
}

Note:

Encode each parameter name and its value with the encoder not the whole URL.

Like, to encode the parameter “user name=j2me & test|” use:

URLEncoder.encode(“user name”) as parameter and URLEncoder.encode(“j2me & test|”) and thus build the whole query string.

So, I added the following line in my Apache server’s ‘mime.types’ configuaration file:

text/vnd.sun.j2me.app-descriptor                jad

And it worked like a charm.

For apache tomcat server it should be added in the “web.xml” file like this:

  <mime-mapping>

        <extension>jad</extension>

        <mime-type>text/vnd.sun.j2me.app-descriptor</mime-type>

  </mime-mapping>

“IECapt is a simple command line utility that uses the Internet Explorer rendering engine to render a web page into a GIF/JPEG/BMP/PNG image file” (Quoted from sourceforge.net). 

It is a written in C++, licensed under GPL and runs in 32 Bit Windows XP/NT/2000. It can be found here.

Sample command:

From windows command line type the following command:

IECapt.exe http://sihantech.wordpress.com thumb.png

This will create an image ‘thumb.png’ in local disk by capturing a screenshot of the given url.

Now we can execute this by PHP using exec() function or by java using Runtime.getRuntime().exec() method.