Continue reading »]]> My Samsung Galaxy Ace’s battery has become very week lately. It has swollen and been discharging really fast. Whenever I used to connect charger , the battery charge level used go up to 100% within minutes and again discharge within an hour when I start using it. It got discharged within minutes from 100% to 0% while using WI-FI or 3G.

Initially I thought , it may be due to age of the phone (2 years), rooting the phone, installing custom ROM (manufacturer knows the phone best ) or due to partitioning SD card to increase internal storage (phone may be unknowingly accessing my slow class 4 SD card frequently). I also consulted some “Gadget Guru” friends of mine but as expected their knowledge was limited to the user’s and market point of view. They asked me to get a new phone as a 3 year old would have suggested me . I completely forgot that fact that in our childhood gadgets we used to change the rechargeable batteries. These days the smart phones are being upgraded so frequently nobody bothers to get a new battery.

Finally I decided to replace the battery for 450 INR and then get a new phone if the phone really had a problem. It has been a week and battery performance has been drastically increased  as if it is a new phone. Here is a screenshot of the battery usage after I charged the battery to only 85%. I read somewhere the battery life increases more when you let the battery discharge below 10% and then charge all the way till 100% (one has to wait even after 100% , phone should say battery is charged.)
Also note that following good practices helps the phone retain charge for longer hours in my experience

• Keep the WI-FI turned off when not in wi-fi area, phone spends a lot of power just searching for signal
• Disable Background data use when not required.
• Create profiles and manage various power settings depending on the usage (Home, work or Car). This feature is available in most of the custom ROMs.
• Reduce screen brightness  at night time.
• Close the apps with Back button of Android because they keep running in the background if you press home button. Apple products does magic in this case by putting the background apps to sleep.

Continue reading »]]> One of my biggest problem with my phone got solved today. I had been using an old Android phone with only 181 Mb of Internal phone storage. As a result my phone starts complaining after installing few apps, especially the ones which can not be moved to SD card. I have a 16GB SD card installed but its of no use when it comes to running more number of apps. Lately I had to uninstall a lot of my favorite apps and rely on the browser, e.g. I never could install Android apps for Facebook, Twitter, Google+ etc. I always used the mobile websites.

Finally I started searching the workaround for the same. I found that a part of my SD card can be partitioned and formatted as linux file system , so that Android OS considers it as part of phone storage. This is possible for phones which are rooted and I was already using custom ROM from Cyanogenmod.

Note: following will wipe all your data in SD card including music and photos.

1. Use Mini Tool Partition Wizard Manager to delete the original SD card partition and create two primary partitions as follows
   1. A FAT32 partition with most of the size of the SD card.
   2. An EXT2 (old type file system format to make sure most of the ROM support it), you can try with EXT3 or EXT4 also but I never tested. I kept this partition as 1 GB, I think I will never run out of this space , adding apps.
2. Click “apply” to commit the partition changes  and format the SD card.
3. Copy and unzip the system.zip file on to the SD card.
4. Put the SD card back in the phone and start the Terminal Emulator app of the rooted phone.
5. copy the file 40int2ext file (found in the system.zip file ) in /system/mnt/etc/init.d directory of the phone. I used the “cp” command and changed the permission of the destination directory for writing file after changing the user to super user (su). You may have to click “allow” while changing the user.
6. That’s it, I rebooted and phone and saw the internal memory has been increased to almost 1 GB.

Wow ! that was great, I immediately loaded the phone with all the apps I always wanted to install.
I was surprised to see that the performance did not decrease noticeably even tough it is a low class SD card. I will continue to test by installing more apps.

Finally a word of caution : Do this only if you fine in case the phone or the card does not work after this experiment.
However if experiment is successful , you will never see the “insufficient storage” or “low memory” error

Source

Continue reading »]]> I have been using python for writing small utility programs. Till now I avoided scripting languages like python because I though shell script is master of everything and works in any linux computer. They also have all programming constructs like loops and conditions etc. However when it came to quickly get some work done, shell script too a lot of time write a error free program. Finally I jumped to python to do some file batch processing.

The most fundamental need to batch file processing is to iterate through all the files in a given directory. I could found several ways to do so using os.walk function but my old linux server had only Python 2.2 and I did not want to FTP files to my local PC to server back and fourth . So here is the code which also works in old version of python.

import os

# finds all the files in a directory recursively 
def listAll(dirName):
    filelist1=[]
    files = os.listdir(dirName)
    for f in files:
        if os.path.isfile(os.path.join(dirName,f)):
            filelist1.append(os.path.join(dirName,f))
        else:
            newlist=listAll(os.path.join(dirName,f));
            filelist1.extend(newlist)			
    return filelist1 
# root directory path
rootdir= '/home/'  

for f in listAll(rootdir):
    print "Absolute Path " + os.path.abspath(f)
    print "File Name"      + os.path.basename(f)
    print "Directory Path" + os.path.dirname(f)
    # Change directory 
    os.chdir(os.path.dirname(f))
    # print current directory 
    os.system("pwd")
    print os.getcwd()
    # check file extension
    if not ( f.endswith(".java") or or f.endswith(".xml")):
        # Do nothing 
        continue

Continue reading »]]>

I don’t remember how many of my friends and colleagues who are qualified engineers and doing the top technology jobs told me that they are bored of their “IT Job” and probably want to join a bank or may be do a cloth business. I always wanted to ask them why didn’t you think about this when you joined Engineering school ? or at  least deciding the major in engineering school ? Like computer science or mechanical engineering ? When I was deciding the same back in 2002 people almost forced me to take Mechanical or Electrical Engineering just because there was a dot com boom in the technology industry. Even at that time I believed that new possibilities are in computer science are way more than what there is in all other fields of engineering combined. By the time I graduated things really changed and I observed that graduated of all other departments of engineering taking up technology jobs and starting to write code for the first time in their lives. Thanks to the companies who only give you puzzles instead of programming question. Had I known that , I could have just practiced puzzles instead of learning to code all 4 years of my undergrad !

I love the above video. It says there aren’t many qualified programmer to fulfill upcoming requirements. Then why is there so much of unemployment despite of thousands of engineering colleges around all offering Computer Science and Information Technology related degree ? I don’t even see any private engineering college investing in heavy machinery for Electrical or Mechanical engineering departments. I found my answer when I toured various engineering colleges for guest lectures. Actually its just the degree. Even a final year student does not raise hand when I ask “Have you written any program in any language ?” I doubt its because they are sky or lack in communication skills. Anyway I highly recommend this video.

Anyway I always felt that I am born to code and this is what I think about few others

However all above are just my opinion. Not trying to belittle any branch of Engineering. I still love electronics, machines and electrical circuits, they are the basis of all computers and its real life applications. Just that I am happy that I studied what I wanted to do and doing what I wanted to study. I am just fortunate to realize this early , most people realize late and hard work in the past remains useless.

Continue reading »]]> As you may have come across news articles that asteroid 2012 DA14 will be fly by earth very closely. It will in fact come closer than the Moon and some Geo stationary satellites.

You can see the live event in SLOOH SpaceCamera if you think you are in a wrong timezone.

Following is the heaven’s above chart.

Ajay Talwar did a fantastic job by calculating the  speed of the asteroid relative to the sky which is very helpful to spot it using a telescope. Note that you need at least a small telescope or good binocular to spot it even when it is closest because the apparent magnitude would be little beyond what unaided human can see at the darkest location.

Here is the approximate schedule created by Ajay Talwar considering the viewer from New Delhi

15th February
23:53 IST – 2012DA14 rises in the constellation of Centaurus, apparent speed 0.44 degrees per minute, Mag 8.8
16th February
00:27 IST – crosses into Hydra, apparent speed 0.71 degrees per minute, Mag 0.78
00:29 IST – close to beta Hya, apparent speed 0.72 degrees per minute, Mag 7.8
00:41 IST – crosses into Crater, apparent speed 0.82 degrees per minute, Mag 7.4
01:02 IST – crosses into Virgo, apparent speed 0.92 degrees per minute, Mag 7.0
01:05 IST – closest approach (approximately for India), apparent speed 0.92 degrees per minute, Mag 6.9
01:10 IST – close to beta Vir, apparent speed 0.91 degrees per minute, Mag 6.9
01:21 IST – crosses into Leo, apparent speed 0.87 degrees per minute, Mag 6.8
01:25 IST – close to beta Leo, apparent speed 0.84 degrees per minute, Mag 6.9
01:44 IST – crosses into Ursa Major, apparent speed 0.69 degrees per minute, Mag 7.2
02:33 IST – close to M109 galaxy, apparent speed 0.34 degrees per minute, Mag 8.4
03:24 IST – crosses into Draco, apparent speed 0.07 degrees per minute, Mag 9.3
04:57 IST crosses into Camelopardalis (headed directly towards Polaris), apparent speed 0.07 degrees per minute, Mag 10.5
Dawn break in Delhi

Astronomer Phill Plait will be doing live hangout during this event , you can catch him at Google Plus.

Continue reading »]]> My last post was about #AdoptAJSR initiative in which JUG Hyderabad is actively involved. Meanwhile I was trying to explore the Websocket API for Java (JSR 356) using glassfish 4 ‘s latest build as reference implementation.

The idea was to use HTML5 websocket API in the front end to communicate with websocket endpoint created in the glassfish server.  To get started with I referred a  similar sample application blogged by Arun Gupta.

In this process I managed to log following bugs against the reference implementation

1. Session object coming as the parameter in @WebSocketClose annotated method is null
2. Session#isOpen method returns NoSuchMethodException
   
   To avoid this situation I have put the code “peer.getRemote().sendString(“Ping”);” in try block so that if it fails , it can gracefully remove that peer instead of ending up in exception.

My app lets you draw freehand lines in the browser and the same gets drawn in real time at every other user’s browser who is accessing this app. If you refresh the page or a new user joins in then the existing state of the drawing is shown the browser.

To create such project one has to go maven way as of now. Following are the major steps you need to care about while creating this project

1. Choose a Maven project in Netbeans

2. The Websocket Java APIs could not be imported in the Java class unless the websocket library is searched in the repository and added to the project

The source code that I created can be accessed from Github. Feel free to download and give feedback or try to create your own version.

You can download the slate demo video and play in any flash enabled browser.

Play this in full screen to see the code.

Further features and future challenges

1. Draw the existing lines slowly (Playback) when a new user joins in so that he gets the context. For this, one needs to block other users ( javaScript thread ) from drawing till the playback is over. or some way to buffer the new drawings till the JavaScript thread is free from playback.
2. Different color and strokes
3. Simultaneous drawing using webworkers.

Continue reading »]]> So many times while jotting down some text quickly (especially over a during call) we search for windows notepad. We forget that we have a full fledged browser always running which is a great software to do anything. In fact I have composed Gmail drafts and sometimes typed in Google to temporarily note down phone numbers and addresses. I found a trick to turn the browser quickly into a text editor/notepad

1. Open a new browser tab
2. Type the following in the address bar and hit Enter
   

   data:text/html, <html contenteditable>

3. You should be able to type in the web page now.. You can also paste text here from your clipboard
   

   data:text/html,<html contenteditable>

4. To make it easily accessible bookmark it on the bookmark toolbar
5. Optionally you can save text like a web page from the browser with Ctrl + S key.

Continue reading »]]> Lately there has been a lot of activity in JUG Hyderabad after introduction to #AdoptAJSR initiative. JUG Hyderabad has taken up JSR 338 (Java Persistence 2.1), JSR-107 (JCACHE – Java Temporary Caching API), JSR-256 (Java API for websocket ) and there has been significant progress. I am a kind of programmer who jumps into code directly before going through pages of theory. So here are some links for quick reference

• Blog post on #AdoptAJSR (Really Concise post by Arun )
• Blog post on Websocket in JavaEE7
• Blog post on Websocket Sample Application
• #AdoptAJSR websocket spec page
• Websocket Java Doc
• Websocket Spec Early Draft
• Websocket RI users mailing list (tyrus)
• Websocket RI Issue tracker ( JIRA )

Meanwhile The Java user group in Hyderabad has gone social and following are the links

• JUG Hyderabad Mailing list
• Meetup (Official Website)
• Twitter
• Google Plus Page
• Google Plus Community

JUG Hyderabad is looking for passionate people who are passionate about JAVA and want to drive the community forward. Do let us know.

Continue reading »]]> Last week I posted about the English-2020 project for improving spoken English world wide and I was also playing around my mobile phone. With the mobile version of English-2020 coming in next few months I came across this interesting site for learning french. Below is a partner post about this site and their apps. I always wanted to learn, hope you find it useful.

The French language is one of the most widely spoken languages in the world. There are currently more than 129 million people that speak French and 70 million of that are native speakers according to a study made by the European Union. This number is expected to increase up to 500 million in 2025 according to Agence universitaire de la Francophonie (AUF) and Laval University. Some study French because it is required in school and some learn this language to impress someone. Hearing someone talk in French, especially the likes of Olivier Martinez and Audrey Tatou, is a major turn on for most men and women. There is something sexy about this language that attracts people. Years ago, the only way to learn French is by going to a language school. With today’s technology, you can now learn this language by using your smartphone. Here are some Android applications that can come in handy when learning French:

PartyPoker France
Who says that learning French can be boring? You can actually have fun playing poker and at the same time learn this language. You can either visit the Partypoker.fr website or download its application in your Android phone. If you know the poker terms, then it will be easier for you to translate what’s on the website. If you are not familiar with them, then you can always click the Google translation on top of your browser. Since poker is mostly about numbers, then you only need to learn a few important terms including Full aux As (Aces Full), Miser le Pot (Bet the Pot), and Cart Ouverte (Open card). Once you have mastered those terms, then you can compete with the other French opponents at PartyPoker. There are different kinds of tournaments available in this poker site, which makes it more fun and exciting. You can also join in anytime you want because the games here run 24/7. Joining this game is a win-win situation because you won’t only have fun playing poker and learn basic French, but also get a chance to win huge cash.

French Translator/Dictionary
This application from GreenLife Apps is perfect for those who want to learn short French sentences. You can type an English sentence and it automatically translates it to French. Or you can type a French sentence so you will know what that means in English. Aside from translating English to French and vice-versa, you will also get a new word each day which you can add to your French vocabulary. The French Translator/Dictionary also gives sentences on how to use that word.

BabelFish Voice: French
French words are quite difficult to pronounce because how it is written is sometimes different from how you say it. Thanks to BabelFish Voice: French, you can now learn how to correctly say the words written in French. This application gives voice translation so all you have to do is speak into the microphone and get a spoken French translation. This will spare you from speaking funny French.

The above site has about 38,000 daily visitors according to wolframalpha.