Android Question 1: android Question 1

Source: Internet
Author: User

Android Question 1: android Question 1

 

1. is the process of Android DVM (Dalvik VM) the process of Linux the process of an application the same concept?

DVM (Dalvik VM) refers to the Virtual Machine of dalvik. Every Android application runs in its own process and has an independent Dalvik Virtual Machine instance. Every DVM is a process in Linux, so it can be considered the same concept. Running in your own DVM process, different apps will not interfere with each other, and will not cause all app processes to crash because of the crash of a DVM.

The Android runtime environment mainly refers to the virtual machine technology Dalvik. All Java programs in Android run on Dalvik VM. Every program on Android has its own thread, and DVM only executes the Dalvik executable file of. dex. Each Android Application has an independent DVM instance at the underlying layer and is executed under its interpretation.

 

2. Similarities and Differences between DVM and JVM in java in Android:

DVM: Dalvik virtual machine
JVM: Java virtual machine

Difference 1: dvm executes the. dex format file. jvm executes the. class file license file. Apk indicates the android package. Jvm executes the. class file.

Difference 2: dvm is a register-based Virtual Machine and jvm execution is a virtual machine based on the virtual stack. The speed of register access is much faster than that of stack. dvm can be optimized based on hardware and is suitable for mobile devices.

Difference 3: The. class file has a lot of redundant information. The dex tool will remove redundant information and integrate all. class files into the. dex file. Reduces I/O operations and improves the search speed of classes.

Contact Us

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: info-contact@alibabacloud.com and provide relevant evidence. A staff member will contact you within 5 working days.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.