JVM memory

In this chapter you will learn:

1. Get the memory in your Java virtual machine

Get the memory in your Java virtual machine

• long totalMemory()
  Returns the total amount of memory in the Java virtual machine.
• long freeMemory()
  Returns the amount of free memory in the Java Virtual Machine.
• long maxMemory()
  Returns the maximum amount of memory that the Java virtual machine will attempt to use.

public class Main {
  public static void main(String[] args) {
    Runtime runtime = Runtime.getRuntime();
    System.out.println("Total memory:"+runtime.totalMemory());
    System.out.println("Free memory:"+runtime.freeMemory());
    System.out.println("Max memory:"+runtime.maxMemory());
  }/*from j  av a  2s  .  co m*/
}

The output:

Total memory:5177344
Free memory:4991032
Max memory:66650112

Next chapter...

What you will learn in the next chapter:

1. Run garbage collector and finalization methods

Java standard stream

Java system property get and set

Current time in millis second and nano second

Random UUID

JVM memory

JVM garbage collector

JVM shutting down

Processor count

OS system commands

Random class

Random value

Random value range

Compile Java source code

Timer and TimerTask