Runtime : freeMemory()

package Runtime;

public class freeMemory {
    public static void main(String args[]){
        Runtime r=Runtime.getRuntime();
        long mem1, mem2;
        Integer someints[] =new Integer[10000];
       
        System.out.println("Total memory is :"+ r.totalMemory());
       
        mem1=r.freeMemory();
        System.out.println("Initial free memory :"+mem1);
        r.gc();
        mem1=r.freeMemory();
        System.out.println("Free memory after garbage collection :"+mem1);
       
        for(int i=0;i<someints.length;i++)
            someints[i]=null;
   
        r.gc();
       
        mem2=r.freeMemory();
        System.out.println("Free memory after collecting "+ "discarded Integers :"+mem2);
    }
}