Java虚拟机是否依赖于机器？

Question

Is the JVM (Java Virtual Machine) platform dependent?

What is the advantage of using the JVM, and having Java be a translated language?

Answer 1

Yes, generally a JVM is platform dependent in the sense that it is implemented for the specific platform.

The advantage of using a JVM is that, at least in theory, it makes code written in Java platform agnostic and so the same code could run on any platform without modification to the code.

Answer 2

There are many advantages to having a virtual machine (such as the Java Virtual Machine - with its' write once, run anywhere promises); among them are -

1. Your application becomes operating system independent
2. Your application becomes architecture independent

In other words, your application becomes (at least somewhat) future-proof as regards to the shifting landscape of competitive vendors. Still (IMO) the biggest advantage is that Java applications and frameworks run the same on Linux, Mac and Windows. Although each does need it's own implementation of the Virtual Machine (eg the actual Java Runtime Environment is platform specific, it is available in source form ).

Answer 3

The parts of the JVM that dialogue with the operating system are platform dependant. But Java bytecode is independant, or at least supposed to be (edge cases probably exist).

The advantage of the JVM is simply to be able to compile once and be able to run executable bytecode on any platform which is supported. This is opposed to how things were before where you had to recompile to suit another OS or processor.

Btw, Java is not a translated/interpreted language like PHP or javascript. It's actually compiled with the JVM acting as a middleman or abstraction layer above an operating system.

Answer 4

JVM itself is not independent. When you download jdk ,you can see that you have to choose you platform at first.You have to get clear your machine and OS type including unix-like ,windows or mac , 32-bit or 64-bit.But we always say that java is a platform-independent programming language,it is because JVM works as a middle-lays between your java application and the underline OS ,thus making java developer can just focus on the same JVM ,ignoring the isomerism of Operating Systems and hardware environments.

Answer 5

JVM is a specification that provides runtime environment in which java bytecode can be executed.

Jvm Interprets your bytecode into Machine Understandable code .

The JVM performs following operation:

 - Loads code
 - Verifies code
 - Executes code
 - Provides runtime environment 

To do this a code has to be written,
So Implementation of specifications is done here(sun provides mostly).
This implemetation is JRE .

JVM ALSO TELL HOW FOLLOWING THINGS MUST HAPPEN:

 - Memory area
 - Class file format
 - Register set
 - Garbage-collected heap
 - Fatal error reporting etc.

So Yes JVM strongly platform dependant,find detail working Here JVM Details