Java data types

Java data types
Data types in java programming language are classified into two main group.
1------>Primitive data types
2------>Reference data types

Details of the data types

JavaScript Introduction

JavaScript Introduction

What do you think about java and javaScript???

Are these same?

No. 

  

Java applets can also run in all browser, but java applets are not enabled in every browser.

New mobile

புதிய மொபைல் அறிமுகம்
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இன்று நாம் பார்க்க போவது Samsung Galaxy Alpha என்ற மிக அதி தொழில்நுட்பத்துடன் கூடிய ஸ்மார்ட்ஃபோன்.

சாம்சங் நிறுவனம் மொபைல் சந்தையில் தொடர்ந்து முதல் இடத்தில் இருக்கிறது. இதற்கு காரணம் பல வகையான மொபைல்களை தொடர்ந்து அறிமுகம் செய்வதுதான். சென்ற ஜூலை மாதம் நான்கு மொபைல்களை அறிமுகம் செய்தது சாம்சங், இப்போது விலை சற்று அதிகம் உள்ள அதிக திறன் மட்டும் தொழில்நுட்பத்துடன் கூடிய ஸ்மார்ட்ஃபோனை வெளியிட இருக்கிறது. இந்த Samsung Galaxy Alpha வரும் செப்டெம்பர் மாதம் இந்தியா உட்பட 150 நாடுகளில் வெளிவர இருக்கிறது.

இதன் விவர குறிப்புகள்:

- 4.7-inch Super AMOLED display with a resolution of 720 x 1280-pixel
- Android 4.4.4 KitKat with TouchWiz
- Exynos 5430 (octa-core, four cores running at 1.8GHz and four more at 1.3GHz)
- 2GB RAM
- 12-megapixel rear camera,
- 2.1-megapixel front cam
- 32GB of internal storage, No microSD card slot
- 4G+ LTE connectivity, Cat. 6 with 300Mbps down/50Mbps up speeds
- 1860mAh battery
WiFi: 802.11 a/b/g/n/ac HT80, MIMO(2x2)
Bluetooth®: 4.0 BLE / ANT+
- 0.26” (6.7mm) thick
Accelerometer, Gyro Sensor, Geomagnetic Sensor, Hall Sensor,
Light Sensor, Proximity Sensor ,Gesture Sensor, Fingerprint
Sensor, HR Sensor என எல்லாமே உள்ளது.

இந்த குறிப்புகளை பார்க்கும் போது இந்த ஸ்மார்ட்போனுக்கு மெமரி கார்ட் இல்லை, ஏனென்றால் தேவையே இல்லை என்று சொல்லலாம்.

இதன் பிரசாசர் Exynos SoC, with quad-core 1.8GHz மற்றும் quad-core 1.3GHz என்பதால் மொபைல் அதிவேகத்துடன் இயங்க வல்லது. Exynos SoC என்பது புதிய தொழில்நுட்பத்துடன் கூடியது.

இதன் பாட்டரி திறன் 1860 mAhதான் என்றாலும் Ultra Power Saving Mode இருப்பதால் மின்சார சேமிப்பு அதிக நாட்கள் வரை வருமாம். போதா குறைக்கு சென்சார் டெக்னாலோஜி வேறு இருக்கிறது.

இந்த மொபைலில்தான் நெட் வேகம் மிக மிக அதிகம் என சாம்சங் நிறுவனம் அறிவித்து இருக்கிறது.

சரி இதன் விலை பார்க்கலாமா? இதன் விலை விவரங்கள் இன்னும் அதிகார பூர்வமாக அறிவிக்கபடவில்லை இருப்பினும் $689 டாலர் என தெரிகிறது, இந்தியாவில் இதன் விலை சுமார் 42,250 ரூபாய் என தெரிகிறது.

evolve of Android

Android Operating System

• Android is a Linux-based smartphone operating system and software platform created by Google.
• Android is an open source operating system which allows developers to access and modified.

Origin of android version

Android beta

• The beta release of Android OS was released on 5 November 2007. 
• The first SDK was released a week later, on 12 November 2007.

Android 1.0

• Android 1.0 was the first commercially available release of the OS.
• It was available on the pioneering device - the T-Mobile G1.
• It was released on October 2008.

Android 1.1

• Android 1.1 was pushed out on 9 February 2009, coinciding with the announcement of the HTC Dream.
• It was available on the twin of the T-Mobile G1.

Android 1.5 (Cupcake)

• Android 1.5 Cupcake was released on 30 April 2009.
• It was the first major Android overhaul.
• it also was the first Android release to be pet-named after a dessert - a tradition that has been kept alive ever since.
• Every subsequent Android release was named after a dessert, whose name started with the next letter of the alphabet.
• 1.5 Cupcake added support for third-party software keyboards, third-party widgets, on-screen keyboard, shoot video, stereo Bluetooth, copy and paste in the web browser, screen auto-rotation, and an option to upload media to YouTube.

Android 1.6 (Donut)

• Android 1.6 Donut was released on 15 September 2009.
• It added text-to-speech, updated Android Market now offered app screenshots, and it introduced support for WVGA screens.
• The camera became faster, and the gallery, camera and camcorder got deeply integrated with each other.

Android 2.x (Eclair)

Android 2.0:-

• Its SDK was released on 26 October 2009.
• Android 2.0 introduced multiple account sync, Microsoft Exchange email support, Bluetooth 2.1, the Quick Contact feature, Live wallpapers,showing a pop-up for call, SMS and email, as soon as you tap on a contact's avatar.
• The camera received new features such as flash support, digital zoom, scene mode, white balance, color effect and macro focus. 
• The web browser UI was updated and some new features were added such as double-tap to zoom.
• It introduced Google Maps Navigation.

Android 2.1:-

• Android 2.1 Eclair Google introduced its first Nexus devices as well 

Android 2.2.x (Froyo)

• Android 2.2.Froyo SDK was released on 20 May 2010.
• Storage access and applications became faster thanks to the added JIT compiler. 
• The web browser got a speed boost too, courtesy of the new JavaScript engine.
• Android 2.2 Froyo also introduced push notifications, USB tethering and Wi-Fi hotspot functionality, an updated Android Market with automatic updates and batch install.
• The Adobe Flash support was another major new feature of the web browser.
• Minor revisions were later released as updates such as Android 2.2.1, 2.2.2, and 2.2.3.

Android 2.3.x (Gingerbread)

• Android 2.3 Gingerbread SDK was released on 6 December 2010. 
• This Android release offered an updated user interface and even better performance optimization.
• It added native support for SIP VoIP internet telephony, improved text input and keyboard accuracy, enhanced copy/paste functionality (word-by-word selection), Near Field Communication (NFC) support, new audio effects such as headphone virtualization and bass boost, new system-wide download manager, and native support for a front-facing camera.
• Developers also received a number of under-the-hood enhancements, giving them lower-level access to audio, graphics, and inputs, plus concurrent garbage collection for increased performance and native support for extra sensors such as gyroscopes and barometers. All this allowed devs to write faster native code.
• Newer phones, which came out of the box with Gingerbread, now used the newer ext4 file system.
• Android 2.3 Gingerbread however, was mainly touted for its enhanced power management, which took a more active approach to dealing with apps, which kept the phone going for much longer.
• As of December 2012, Gingerbread is still the most widely used release of Android in the world.Minor revisions were later released as updates such as Android 2.3.1, 2.3.2, 2.3.4, 2.3.5, 2.3.6, and 2.3.7.\
• Among the more important updates of those from a user's point of view is Android 2.3.4 Gingerbread (April 2011) introduced support for voice or video chat via Google Talk.
• Android 2.3.5 Gingerbread (July 2011) introduced an improved Gmail app, camera enhancements, and an even better battery efficiency.
• Google continued the Nexus lineup with the launch of the Samsung-made Google Nexuss (December 2010), which was the first phone publicly released with Android 2.3 Gingerbread, and also the first phone to support NFC on both hardware and software level.

Android 3.x (Honeycomb)

• Android 3.0 Honeycomb SDK was released on 22 February 2011. 
• It was Android's tablet-only version and was available concurrently with Android Gingerbread for phones.
• Android Honeycomb introduced a new all-touch user interface, which did not rely on any physical navigation buttons. Unfortunately, it was plagued by performance issues throughout its product life.
• Besides the visual differences, Honeycomb was first to introduce native hardware acceleration and support for multi-core processors. Honeycomb offered support for video calls over Google Talk even before Gingerbread smartphones did (the feature was only released in Android 2.3.4).
• Later on Honeycomb was updated to Android 3.1 and 3.2 before Gingerbread and Honeycomb were both replaced by Android 4.0 Ice Cream Sandwich.
• Android 3.1 added support for USB accessories such as external keyboards and pointing devices, joysticks and gamepads. Android 3.2 brought along refinements in performance via optimizations for a wider range of tablet devices.
• Android 3.x Honeycomb release was not accompanied by a dedicated Nexus device, but Google widely used the Motorola XOOM as an ambassador and main demonstration platform for Honeycomb.

Android 4.0.x (Ice Cream Sandwich)

• The Android 4.0.x Ice Cream Sandwich SDK was released on 19 October 2011.
• Android ICS was released along with the Google Galaxy Nexus(November 2011) - the next successor in the popular Nexus lineup.
• Android Ice Cream Sandwich or ICS, as it is better known, integrated the phone and tablet branches of Android into a single edition with a common interface, which again didn't rely on physical navigation buttons.
• One of the most prominent changes in the UI was that the Widgets were now moved to a tab of their own in the main menu.
• Numerous other changes were introduced too, such as a new typeface throughout the UI - Roboto, the ability to launch apps from the lockscreen, support for real-time speech to text dictation, Face Unlock, Google Chrome web browser came preinstlalled with tabs and syncing of bookmarks, camera with time-lapse and panorama and a built-in photo editor, data usage analysis, and new calendar and mail apps. 
• The UI graphics and animations got hardware acceleration and Wi-Fi Direct functionality was now supported natively.
• Minor revisions were later released as updates such as Android 4.0.1 and 4.0.2.
• In December 2011 Android 4.0.3 was released, fixing most bugs spotted in the previous releases plus adding enhanced video stabilization.
• Android 4.0.4 is another minor update, which further enhanced the performance of the OS.
• Further minor revisions were later released as updates ranging from Android 4.0.4 to 4.0.5 and 4.0.6.

Android 4.1.x (Jelly Bean)

• Android 4.1 Jelly Bean SDK was released on 9 July 2012. 
• A new version 4.2 was released later on under the same Jelly Bean moniker.
• Android 4.1 Jelly Bean has a focus on performance, aiming to get rid of stutter by introducing Vsync (Vertical synchronization) of the timing of the frames output and the screen's refresh rate. Also, Jelly Bean adds triple buffering in graphics.
• Instead of a smartphone, Google chose to display a tablet along with its Android 4.1 Jelly Bean release - the Google Nexus 7(July 2012) was meant to show that Jelly Bean looked equally good on a tablet screen.
• Beyond performance, there are other interesting features such as, offline voice recognition and dictation, expandable notifications, USB audio output and HDMI multichannel audio output, App encryption and Smart App updates. 
• The Roboto font has also been refreshed, widgets are now dynamically resizable, and word prediction has been updated, too. 
• Google Now is also a pretty big deal - it processes various data about your location, time of day, your schedule, etc. - and it shows you a pack of information cards, which it deems important to you in the current context. It also supports an advanced natural language voice search function, which is quite flexible.
• Minor revisions of 4.1 Jelly bean were later released as updates such as Android 4.1.1 and 4.1.2.

Android 4.2.x (Jelly Bean)

• Android 4.2 Jelly Bean builds on the foundations of 4.1 Jelly Bean and adds many new features. 
• There is now support for multiple user accounts on tablets, native settings shortcuts in the notifications pane, gesture typing (ala Swype), wireless screen streaming via Wi-Fi Direct (over the Miracast protocol), widgets on the lockscreen, support for USB audio docks, redesigned camera app with HDR mode, Photo Sphere capturing and a built-in editor with filters, as well as further stability improvement.
• A minor revision of Android 4.2 was later released as an update - Android 4.2.1. Most importantly it added native support for Bluetooth gamepads and joysticks.
• The release of the Android 4.2 was supported with the announcement of a fourth Nexus smartphone - the LG-made Google Nexus 4 (November 2012).
• Not only that, but Google also unveiled a 10-inch tablet - the Samsung-made Google Nexus 10

Android 4.3.x (Jelly Bean)

• Google announced Android Jelly Bean 4.3 in July 2013. Along with the announcement, Google also unveiled the 2nd generation Nexus 7 tablet, which was the first device to ship with Android 4.3 out of the box.
• The improvements introduced by Android 4.3 are mostly marginal from a user's point of view:

• Bluetooth LE (a.k.a. Bluetooth Smart) support
• OpenGL ES 3.0 support, allowing for improved game graphics
• Restricted access mode for user profiles (Kid mode or Guest mode)
• Virtual surround sound by Fraunhoffer
• Filesystem write performance improvement by "trim" support
• Auto-complete in the dialer of the Phone app
• Bluetooth AVRCP 1.3 support - displays track names when streaming to a stereo.
• Faster user switching
• Location detection through Wi-Fi even with Wi-Fi off
• Improved Photo Sphere
• 4K resolution video capture support
• Background Wi-Fi location still runs even when Wi-Fi is turned off
• Many security enhancements, performance enhancements, and bug fixes

Android 4.4 (Kit Kat)

Rumored to be called "Key Lime Pie", the next version of Android was announced on 3 September 2013 under the name KitKat (with the endorsement of Nestle).

First program in java

Java first program and explanation

public class Hello

• class is a keyword, which is identifier used to declare a new class (Hello is a new class).

public static void main(String[] args)

• This is main method of the class.
• It is suggests that program will begin executing.
• All of the java program begin their execution by calling main().
• Public keyword is an access specifier which allows to control the visibility of a java program.
• Here the main () must be declared public.
• static allows main () to be called without declaring the objects.
• There is only one parameter in main () i.e. String args[], basically it is an array of instances of the string class.

System.out.println("Hello World!)

• Hello World! - this line used to display the string.
• The println() is a method which is used to take the cursor on to a new line.

Features of Java

Features of Java
Simple
Secure
Portable
Object Oriented
Multithreaded
High Performance
Dispersed
Dynamic
Simple

• Java is a simple and easy to understand. That mean is syntax's are very clear.

Secure

• Java provides a secure mean of creating internet application.
• Java provides secure way to access web applications.

Portable

• Java programs can be run on any platform.
• Java program can be transfer over world wide web(eg applets)

Object-oriented

Java programming is object-oriented programming language.

Java and other languages

Java vs C# & Java vs C++

Here are differences between java and C#.

Java added and removed some feature from C++.

Java environment

Setting up your Java development                               environment

• In this section you will get instruction for downloading and installing JDK and using eclipse IDE

• The JDK include a set of command line tools for compiling and running your code.

• Eclipse is a popular open source IDE for Java development.It handles basic tasks, such as code compilation and setting up a debugging environment, so that you can focus on writing and testing code.You need an installed JDK in order to use Eclipse for Java development.

Install JDK 6

Follow these steps to download and install JDK 6:

1. Browse to Java SE Downloads and click the Java Platform (JDK) box to display the download page for the latest version of the JDK (JDK 6, update 21 at the time of this writing).
2. Click the Download button.
3. Select the operating system platform you need.
4. You will be asked for your account username and password. Enter them if you have an account, sign up if you don't, or you can click Continue to skip this step and proceed to the download.
5. Save the file to your hard drive when prompted.
6. When the download is complete, run the install program. (The file you've just downloaded is a self-extracting ZIP file that is also the install program.) Install the JDK to your hard drive in an easy-to-remember location (such as C:\home\jdk1.6.0_20 on Windows or ~/jdk1.6.0_20 on Linux). It's a good idea to encode the update number in the name of the install directory you choose.

You now have a Java environment on your machine. Next, you will install the Eclipse IDE.

Install Eclipse

To download and install Eclipse, follow these steps:

1. Browse to Eclipse Galileo Sr2 Packages.
2. Click on Eclipse IDE for Java Developers.
3. Under Download Links on the right-hand side, select your platform.
4. Select the mirror you want to download from, then save the file to your hard drive.
5. Extract the contents of the .zip file to a location on your hard drive that you'll be able to remember easily (such as C:\home\eclipse on Windows or ~/eclipse on Linux).

Set up Eclipse

The Eclipse IDE sits atop the JDK as a useful abstraction, but it still needs to access the JDK and its various tools. Before you can use Eclipse to write Java code, you have to tell it where the JDK is located.

To set up your Eclipse development environment:

1. Launch Eclipse by double-clicking on eclipse.exe (or the equivalent executable for your platform).
2. The Workspace Launcher will appear, allowing you to select a root folder for your Eclipse projects. Choose a folder you will easily remember, such as C:\home\workspace on Windows or ~/workspace on Linux.
3. Dismiss the Welcome to Eclipse screen.
4. Click Window > Preferences > Java > Installed JREs. Figure 1 shows the setup screen for the JRE:

   Figure 1. Configuring the JDK used by Eclipse

   
5. Eclipse will point to an installed JRE. You need to make sure you use the one you downloaded with JDK 6. If Eclipse does not automatically detect the JDK you installed, click Add... and in the next dialog Standard VM, then click Next.
6. Specify the JDK's home directory (such as C:\home\jdk1.6.0_20 on Windows), then click Finish.
7. Confirm that the JDK you want to use is selected and click OK.

Eclipse is now set up and ready for you to create projects and compile and run Java code. The next section will familiarize you with Eclipse.

The Eclipse development environment

The Eclipse development environment has four main components:

• Workspace
• Projects
• Perspectives
• Views

The primary unit of organization in Eclipse is the workspace. A workspace contains all of your projects. A perspective is a way of looking at each project (hence the name), and within a perspective are one or more views.

The Java perspective

Figure 2 shows the Java perspective, which is the default perspective for Eclipse. You should see this perspective when you start up Eclipse.

Figure 2. Eclipse Java perspective

The Java perspective contains the tools you need to begin writing Java applications. Each tab shown in Figure 2 is a view for the Java perspective. Package Explorer and Outline are two particularly useful views.

The Eclipse environment is highly configurable. Each view is dockable, so you can move it around in the Java perspective and place it where you want it. For now, though, stick with the default perspective and view setup.

Create a project

Follow these steps to create a new Java project:

1. Click on File > New > Java Project ... and you will see a dialog box open like the one shown in Figure 3:

   Figure 3. New Java Project wizard

   
2. Enter Intro as the project name and click Finish.
3. If you want to modify the default project settings, click Next. (This is recommended only if you have experience with the Eclipse IDE.)
4. Click Finish to accept the project setup and create the project.

Introduction to Java

 Introduction to java 

 History

• Java is programming language.
• It created by James Gosling from sun microsystems in 1991. The first publicly available version of Java (Java 1.0) was released in 1995.
• Sun Microsystems was acquired by the Oracle Corporation in 2010.pa