Linux and native language

Question

Is it true that Android is a version of Linux? I have read that it is. Linux is a re-written version of Unix, right? Unix was written in C, right? I assume that Linux was written mostly or entirely in C++.

The thing that is confusing to me is that most programming for Android is done in Java. It appears that even MonoDroid executes Java. This seems strange to me. It seems to me that it would be more efficient if the MonoDroid runtime were written in C++ instead of Java.

Sam Hobbs · Answer

A logical explanation for using Java is portability but even Java source code would need to be modified for other UIs in other OSs.

Vulpes · Answer

I don't know why Google chose to write the UI part of Android in Java rather than C++ but given the Oracle court case they certainly must be regretting it now! It also makes like difficult for anyone wanting to write apps in any language other than Java. Even C/C++ developers using the NDK have to call into the Java API for UI services! MonoDroid as I understand it does likewise wrapping the Java API within the MonoDroid API. This means that the Mono runtime and Dalvik VM both have to be present at the same time which doesn't augur well for either memory usage or performance. One other option I've noticed for Android development is Basic4Android (see http://www.basic4ppc.com/ ) which apparently produces native Android apps with no extra runtimes or dependencies. This and the way the language is structured suggests to me that it must compile down to Java code which then runs on the Dalvik VM.

Mahesh Chand · Answer

I wonder if Java was used to support Web. I know C++ has its limitations when it comes to the Web development. Also sometimes decision of building a tool also depends on its Architect. If I build a tool even I think Java is better suited for it but I will build it in C# ;).

owen huddlestone · Answer

Yes it is Android is a version of Linux is using as its operating system.

Sam Hobbs · Answer

What is Android? | Android Developers is a description of Android. vs-android is one of three ways I found to do Android development using C/C++. That is not much related to MonoDroid except it indicates it is relevant to ask why MonoDroid is developed using Java. Also there is something called the NDK that can be used to create portions of an Android application in C/C++ in which performance is critical.

Suthish Nair · Answer

That was somthing new to me :). After some research came to know Android uses Linux as its operating system.