A DESCRIPTION OF THE REQUEST :
I suggest to add

    public static native xxx[] newUninitialziedXxxArray(int size);

set of methods to java.lang.reflect.Array for all primitive types except boolean. These methods will allow to create uninitialized primitive arrays
when initial element values do no matter. For instance in java.util.Arrays

    public static char[] copyOf(char[] original, int newLength) {
// char[] copy = new char[newLength];
       char[] copy = java.lang.reflect.Array.newUninitializedCharArray(newLength);
        System.arraycopy(original, 0, copy, 0, Math.min(original.length, newLength));
        return copy;
    }

and many other places all over JDK.


JUSTIFICATION :
Zeroing arrays is expensive. This test

        long t0 = System.currentTimeMillis();
        for(int i = 0; i < 1000; i++) {
              byte[] a = new byte[n];
        }
        System.out.println(System.currentTimeMillis() - t0);

shows < 1ms for n = 1 and ~500 ms for n = 1000000 on my PC. Creating uninitialized arrays will boost performance.


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
java.lang.reflect.Array.newUninitializedXxxArray returns xxx array with uninitialized elements.