Android Learning path one Android architecture

An Android architecture

Two local libraries

The local library of C + + from the Open source community provides the necessary services for the Android application layer. They include:

Webkit

A high-speed web rendering engine that has been used by Safari, Chrome, and many other browsers.

Sqlite

A full-featured SQL database

Apache Harmony

Open-source Java implementations

Opengl

3D Image Rendering Library

Openssl

Secure Sockets Layer

Three DALVK virtual machines

Understanding DALVK needs to start from a Java perspective, and understand the differences between them, recommend the following articles

The difference between a Java virtual machine and a Dalvik virtual machine

Android Virtual Machine Dalvik draws controversy constantly

1. Registers and stacks

one of the first differences between the Dalvik and the standard Java Virtual machine (JVM) is that the Dalvik is based on a register, and the JVM is stack-based.

2. Operating Environment

Another big difference between Dalvik and Java is that the operating environment--dalvik optimized to allow instances of multiple virtual machines to run concurrently in limited memory, and each Dalvik application executes as a standalone Linux process.

Four Linux Systems

The value of the movement

Security

Android Learning path one Android architecture