Share
VIDEOS 1 TO 50
Should an Android dev learn anything other than Java?
Should an Android dev learn anything other than Java?
Published: 2013/09/27
Channel: Ask A Dev
Difference between java and android
Difference between java and android
Published: 2016/05/03
Channel: Makwana Ranjit
Comparison of Java and Android API Top # 8 Facts
Comparison of Java and Android API Top # 8 Facts
Published: 2015/10/27
Channel: Ashutosh Choksi
Java vs C app performance – Gary explains
Java vs C app performance – Gary explains
Published: 2016/05/03
Channel: Android Authority
Java Vs Kotlin - Which Is Better ?
Java Vs Kotlin - Which Is Better ?
Published: 2017/05/20
Channel: Play4Tech
Android vs. iOS - Differences That Matter
Android vs. iOS - Differences That Matter
Published: 2016/04/14
Channel: Android Authority
HTML5 Apps VS Native Apps
HTML5 Apps VS Native Apps
Published: 2015/06/04
Channel: Android Authority
image comparison based on pixels  in java
image comparison based on pixels in java
Published: 2016/11/28
Channel: seetha ramaiah Vadde
kotlin vs Java   clearing your doubts
kotlin vs Java clearing your doubts
Published: 2017/05/20
Channel: Hitesh Choudhary
What is an API?
What is an API?
Published: 2015/06/19
Channel: MuleSoft Videos
Should I Learn Java or JavaScript?
Should I Learn Java or JavaScript?
Published: 2014/03/11
Channel: Techy Help
Will Kotlin replace Java? | Is Java Dead?
Will Kotlin replace Java? | Is Java Dead?
Published: 2017/05/19
Channel: Telusko Learnings
What Programming Language Should I Learn?
What Programming Language Should I Learn?
Published: 2014/06/25
Channel: Koder Boat
Performance Comparison; Java, Python and Go on App Engine
Performance Comparison; Java, Python and Go on App Engine
Published: 2013/06/01
Channel: Google Developers
Explaining to Granpa Why to use Kotlin instead of Java #droidconit #turin
Explaining to Granpa Why to use Kotlin instead of Java #droidconit #turin
Published: 2016/04/08
Channel: Enrico Carraro
Should I Learn Java or Python?
Should I Learn Java or Python?
Published: 2013/09/29
Channel: Question Everything
How to compare two dates by using compareto() method in java
How to compare two dates by using compareto() method in java
Published: 2016/03/29
Channel: competitiveexamsmaterial
Comparing Strings in Java, == and .equals();
Comparing Strings in Java, == and .equals();
Published: 2012/05/10
Channel: NetbeansTutorials
Difference between "== operator" and "equals() method"  in java?
Difference between "== operator" and "equals() method" in java?
Published: 2014/04/30
Channel: DURGA EDUCATION
REST API concepts and examples
REST API concepts and examples
Published: 2014/07/14
Channel: WebConcepts
Kotlin is here for Android.  Is Java dead Now ?
Kotlin is here for Android. Is Java dead Now ?
Published: 2017/05/18
Channel: Hitesh Choudhary
Kotlin and Java differences
Kotlin and Java differences
Published: 2017/05/25
Channel: Maitreyi App
Difference between Java vs Javaw vs Javaws
Difference between Java vs Javaw vs Javaws
Published: 2014/08/23
Channel: Durga Software Solutions
Adv Java || Differences between Http Methods  GET  and POST Part -1
Adv Java || Differences between Http Methods GET and POST Part -1
Published: 2016/08/22
Channel: Durga Software Solutions
java vs kotlin comparison | kotlin and java in Android Development Hindi/Urdu
java vs kotlin comparison | kotlin and java in Android Development Hindi/Urdu
Published: 2017/07/13
Channel: Daniyal Ak
[Android application] Compare code between Kotlin and Java
[Android application] Compare code between Kotlin and Java
Published: 2017/06/09
Channel: Android Tutorial
Java vs C++
Java vs C++
Published: 2014/04/28
Channel: LearnToProgram: Become a Web or Mobile Developer
Java vs Python Platforms Comparison
Java vs Python Platforms Comparison
Published: 2014/06/18
Channel: Alexander Bykovsky
Larry Wall: 5 Programming Languages Everyone Should Know
Larry Wall: 5 Programming Languages Everyone Should Know
Published: 2011/06/13
Channel: Big Think
Java 8 Stream and RxJava comparison: patterns and performances by José Paumard
Java 8 Stream and RxJava comparison: patterns and performances by José Paumard
Published: 2015/11/11
Channel: Devoxx
Differences Between C and Java
Differences Between C and Java
Published: 2013/02/25
Channel: Q Liu
Android Vs. iOS: Which is The Best If You
Android Vs. iOS: Which is The Best If You're A Software Developer?
Published: 2016/02/26
Channel: Simple Programmer
Corejava-Basics-Difference b/w C, Cpp and Java
Corejava-Basics-Difference b/w C, Cpp and Java
Published: 2015/11/19
Channel: Durga Software Solutions
#1.3 Understand the Differences between JVM vs JRE vs JDK in java in one video
#1.3 Understand the Differences between JVM vs JRE vs JDK in java in one video
Published: 2017/06/16
Channel: Smartherd
14.11 HashMap and HashTable in Java
14.11 HashMap and HashTable in Java
Published: 2016/04/18
Channel: Telusko Learnings
Core Java Training | Difference b/w Java & others [C & C++]  by Nagoor Babu
Core Java Training | Difference b/w Java & others [C & C++] by Nagoor Babu
Published: 2016/08/31
Channel: Durga Software Solutions
Java v/s C++ (In Hindi) - A Bold War Between Languages
Java v/s C++ (In Hindi) - A Bold War Between Languages
Published: 2016/12/07
Channel: 3BrosTech
When to use Abstract class and When to use Interface in Java
When to use Abstract class and When to use Interface in Java
Published: 2016/10/06
Channel: Siva Reddy
Python Vs. Java For Intermediate Developers
Python Vs. Java For Intermediate Developers
Published: 2011/09/19
Channel: Biz of Tech
How to compare two Strings in java?
How to compare two Strings in java?
Published: 2016/03/09
Channel: competitiveexamsmaterial
Difference between comparable and comparator interface in java
Difference between comparable and comparator interface in java
Published: 2013/06/20
Channel: Shweta Dubey
Java API | Developing Restful APIs | Rest API In Java | Java Tutorial | Java Training | Edureka
Java API | Developing Restful APIs | Rest API In Java | Java Tutorial | Java Training | Edureka
Published: 2017/04/12
Channel: edureka!
Translating Java to Swift
Translating Java to Swift
Published: 2014/12/21
Channel: Cody Henrichsen
C  Vs Java  - Difference Between C And Java
C Vs Java - Difference Between C And Java
Published: 2017/01/16
Channel: MAD differences
Comparison of  the three Cursors of Java (Collection Framework)
Comparison of the three Cursors of Java (Collection Framework)
Published: 2014/03/08
Channel: Durga Software Solutions
What is the difference between Serializalble and Externalizable interface Java Interview Question An
What is the difference between Serializalble and Externalizable interface Java Interview Question An
Published: 2014/01/10
Channel: Interview Dot
C# and Java Comparison
C# and Java Comparison
Published: 2017/01/29
Channel: Ahmed Ali
ADV JAVA || Differences between ServletConfig and ServletContext Part  - 1
ADV JAVA || Differences between ServletConfig and ServletContext Part - 1
Published: 2016/08/21
Channel: Durga Software Solutions
How Long Does It Take To Learn To Code For Java & Android?
How Long Does It Take To Learn To Code For Java & Android?
Published: 2017/01/14
Channel: Java Programming For Beginners
14.5 LinkedList vs ArrayList in Java
14.5 LinkedList vs ArrayList in Java
Published: 2016/04/04
Channel: Telusko Learnings
NEXT
GO TO RESULTS [51 .. 100]

WIKIPEDIA ARTICLE

From Wikipedia, the free encyclopedia
Jump to: navigation, search

This article compares the application programming interfaces (APIs) and virtual machines (VMs) of the programming language Java and operating system Android.

While most Android applications are written in Java-like language, there are some differences between the Java API and the Android API, and Android does not run Java bytecode by a traditional Java virtual machine (JVM), but instead by a Dalvik virtual machine in older versions of Android, and an Android Runtime (ART) in newer versions, that compile the same code that Dalvik runs to Executable and Linkable Format (ELF) executables containing machine code.

Java bytecode in Java Archive (JAR) files is not executed by Android devices. Instead, Java classes are compiled into a proprietary bytecode format and run on Dalvik (or compiled version thereof with newer ART), a specialized virtual machine (VM) designed for Android. Unlike Java VMs, which are stack machines (stack-based architecture), the Dalvik VM is a register machine (register-based architecture).

Dalvik has some traits that differentiate it from other standard VMs:[1]

  • The VM was designed to use less space.
  • The constant pool has been modified to use only 32-bit indexes to simplify the interpreter.
  • Standard Java bytecode executes 8-bit stack instructions. Local variables must be copied to or from the operand stack by separate instructions. Dalviik instead uses its own 16-bit instruction set that works directly on local variables. The local variable is commonly picked by a 4-bit virtual register field.

Because the bytecode loaded by the Dalvik virtual machine is not Java bytecode and due to the way Dalvik loads classes, it is impossible to load library packages as JJAR files. A different procedure must be used to load Android libraries, in which the content of the underlying dex file must be copied in the application private internal storage area before it is loaded.[2]

System properties[edit]

As is the case for the Java SE class System, the Android System class allows retrieving system properties. However, some mandatory properties defined with the Java virtual machine have no meaning or a different meaning on Android. For example:

  • java.version property returns 0 because it is not used on Android.
  • java.specification.version invariably returns 0.9 independently of the version of Android used.
  • java.class.version invariably returns 50 independently of the version of Android used.
  • user.dir has a different meaning on Android.
  • user.home and user.name properties do not exist on Android.

Class library[edit]

Current versions of Android use the latest Java language and its libraries (but not full graphical user interface (GUI) frameworks), not the Apache Harmony Java implementation, that older versions used. Java 8 source code that works in latest version of Android, can be made to work in older versions of Android.

java.lang package[edit]

By default, the default output stream System.out and System.err do not output anything,[3] and developers are encouraged to use the Log class, which logs Strings on the LogCat tool.[4] This has changed at least from HoneyComb, and they now output to the log console also.

Graphics and widget library[edit]

Android does not use the Abstract Window Toolkit nor the Swing library. User interfaces are built using View objects. Android uses a framework similar to Swing, based on Views rather than JComponents. However, Android widgets are not JavaBeans: the Android application Context must be provided to the widget at creation.

Look and feel[edit]

Android widget library does not support a pluggable look and feel architecture. The look and feel of Android widgets must be embedded in the widgets. However, a limited ability exists to set styles and themes for an application.[5]

Layout manager[edit]

Contrary to Swing where layout managers can be applied to any container widget, Android layout behavior is encoded in the containers.[6]

java.beans package[edit]

Android includes only a small subset of the java.beans package (PropertyChangeEvent and related classes).

See also[edit]

References[edit]

  1. ^ Rose, John (2008-05-31). "with Android and Dalvik at Google I/O". Retrieved 2008-06-08. 
  2. ^ Fred Chung (2011-07-28). "Custom Class Loading in Dalvik". Google. Retrieved 2011-11-27. 
  3. ^ "Android Debug Bridge". Google. Retrieved 2009-05-31. By default, the Android system sends stdout and stderr (System.out and System.err) output to /dev/null. 
  4. ^ "Reading and Writing Logs". Google. Retrieved 2011-11-27. 
  5. ^ "Applying Styles and Themes". Google. Retrieved 2011-09-03. 
  6. ^ "Common Layout Objects". Google. Retrieved 2011-09-03. 

Disclaimer

None of the audio/visual content is hosted on this site. All media is embedded from other sites such as GoogleVideo, Wikipedia, YouTube etc. Therefore, this site has no control over the copyright issues of the streaming media.

All issues concerning copyright violations should be aimed at the sites hosting the material. This site does not host any of the streaming media and the owner has not uploaded any of the material to the video hosting servers. Anyone can find the same content on Google Video or YouTube by themselves.

The owner of this site cannot know which documentaries are in public domain, which has been uploaded to e.g. YouTube by the owner and which has been uploaded without permission. The copyright owner must contact the source if he wants his material off the Internet completely.

Powered by YouTube
Wikipedia content is licensed under the GFDL and (CC) license