Two versions of the same java program from which you are throwing a memory error and the other is not. Can't find out why?

I wrote a java program that tries to assign 2/3 of the heap memory to a byte array and then assign the remaining 1/3 of the heap to another byte array. I have two versions, one of which is throwing an OutOfMemory error and the other is not. Below are my programs.

Version1 - which throws an OutOfMemory error

public class MemoryTest
{
    public static void main(String[] args)
    {
        System.out.println( Runtime.getRuntime().totalMemory() );
        {
            byte[] b1 = new byte[(int) (Runtime.getRuntime().maxMemory() * 0.6)];
        }


        byte[] b2 = new byte[(int) (Runtime.getRuntime().maxMemory() * 0.3)];

        System.out.println( Runtime.getRuntime().totalMemory() );
    }
}

      

        
        
        
      

    

Version 2 - works fine

public class MemoryTest
{
    public static void main(String[] args)
    {
        System.out.println( Runtime.getRuntime().totalMemory() );
        {
            byte[] b1 = new byte[(int) (Runtime.getRuntime().maxMemory() * 0.6)];
        }

        int i=0; //create and initialize which resolves the OutOfMemory issue. No idea how this makes a difference.

        byte[] b2 = new byte[(int) (Runtime.getRuntime().maxMemory() * 0.3)];

        System.out.println( Runtime.getRuntime().totalMemory() );
    }
}

      

        
        
        
      

    

I checked gc and cleared b1 memory during b2 initialization in case of version 2. But the same does not happen with version 1.

I can't seem to find out how int initialization makes a difference? Can someone explain why version 1 is throwing an OutOfMemory error and why version 2 is not?

OS: Windows 7

Java version: 1.8