Finding out system RAM via Java

Question

I am writing a program in which i need to do a minimum system RAM validation. How do i go about calculating the RAM of the machine that is executing the code in its JVM ?

Answer 1

I think it is not possible with pure java at all.

Within the JVM you can only mesure the JVM-ram not the System RAM. http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/management/MemoryMXBean.html

You'll need a piece of native code.

Answer 2

You can have a look into Runtime class:

Runtime.getRuntime().maxMemory();

but from Runtime docs:

Returns the maximum amount of memory that the Java virtual machine will attempt to use. If there is no inherent limit then the value Long.MAX_VALUE will be returned