Drivers: display driver, camera driver, flash memory driver, binder (IPC) driver, keyboard driver, WiFi driver, audio driver and power management. The Linux kernel is also the abstraction layer of hardware and software stack. The former is not only compatible with the function functions that most java languages need to call, but also includes Android core library, such as android.os,, dia, etc The latter is a register based Java virtual machine, which mainly realizes the important functions such as life cycle management, stack management, thread management, security and exception management, garbage collection and so on.Īndroid core system services depend on the Linux kernel, such as security, memory management, process management, network protocol stack and driver model. SQLite is an acid compliant relational database management system, which is included in a relatively small C program OpenGL (Open Graphics Library) is a specification that defines a cross programming language and cross platform application program interface (API), which is used to generate two-dimensional and three-dimensional images.Īndroid runtime includes core library and Dalvik virtual machine. The system library includes 9 subsystems, namely layer management, media library, SQLite, OpenGL estate, freetype, WebKit, SGL, SSL and libc. Based on this reuse mechanism, users can easily replace various application components of the platform itself. Moreover, any application can publish its own functional modules, while other applications can use these published functional modules. On the Android platform, developers can fully access the API framework used by the core application. The application framework layer includes 10 parts: activity manager, window manager, content provider, view system, package manager, phone manager, resource manager, location manager, notification manager and XMPP service. This layer is the basis of Android application development, and developers mostly deal with it. At the same time, developers can use the Java language to design and write their own applications, which are equal and friendly with those core applications. This layer provides some core application packages, such as e-mail, SMS, calendar, map, browser and contact management. From top to bottom, there are four layers: application layer, application framework layer, system runtime layer and Linux kernel layer. The system architecture of Android adopts the idea of layered architecture. It was acquired by Google in 2005 and officially demonstrated the system to the outside world on November 5, 2007.
The Android operating system was originally developed by Andy Rubin.
It is a lightweight, short and powerful mobile system, and an open system for mobile phones. Google designed the Android logo as a green robot, indicating that the Android system is in line with the concept of environmental protection.
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