Android Architecture

Hello friends

                We have already see the introduction to android (read first if not). Today we see the architecture of android. Architecture of android means a things that together become a platform to run android application easily in a small touch screen device.

There are main five part in android Architecture

1        1)      Linux kernel (Figure mark as 1)

2        2)      Libraries (Figure mark as 2)

3        3)      Android Runtime (Figure mark as 3)

4        4)      Application Framework (Figure mark as 4)

5        5)      Application (Figure mark as 5)

The above five part combine and form a Android Architecture. Lets see each in detail

1 1)    Linux kernel : In Android Architecture the bottom of the layer is Linux(See figure mark as 1).This layer provides a basic system functionality like process management, device management like Camera, Keypad, Display, Bluetooth, etc. Also, the kernel handles all the things that Linux is really good at such as networking and a vast array of device drivers, which take the pain out of interfacing to peripherals hardware.

2 2)     Libraries :  In Android Architecture on the top of Linux kernel there is a set of libraries including open-source Web browser engine webkit, well known libc, media framework, SGL, Free Type, SQLite database which is a useful repository for storage and sharing of application data, libraries to play and record audio and video, SSL libraries responsible for internet security etc.

3 3)      Android Runtime: In Android Architecture this is a third section that is available on the second layer from the bottom. This section provide a key component called Dalvik Virtual Machine (Detail we discuss in later post) just like a java virtual machine (JVM) but it is specially designed and optimized for Android.

The Dalvik Virtual Machine (DVM) makes use of Linux core features like memory management and multi-threading, which is intrinsic in the java language. The Dalvik VM enables every Android Application to run in its own process, with its own instance of the Dalvik Virtual machine.

4 4)      Application Framework : The Application Framework layer provides many higher-level services to application in the form of java classes. Application developers are allowed to make use of these service in their applications.

5 5)      Application : You will find all the Android application at the top layer. You will write your application to be installed on the layer only. Example of such application are Contacts, Books, Browser, Games, or any other application you installed in your device.