@Nonnull
	public static Number shiftLeft(@Nonnull Number value, @Nonnull Number shift) {
		// Check for widest types first, go down the type list to narrower types until reaching int.
		if (value instanceof Long) {
			return value.longValue() << shift.longValue();
		} else {
			return value.intValue() << shift.intValue();
		}
	}
@Test
	void testShiftLeft() {
		assertEquals(2 << 1, NumberUtil.shiftLeft(2, 1));
		assertEquals(2L << 1, NumberUtil.shiftLeft(2L, 1));
	}