@Override public boolean remove(long key1, int key2) {
        return super.remove0(key1, key2);
    }
@Test
    public void testRemove() {
        final long key1 = randomKey();
        final int key2 = randomKey();
        insert(key1, key2);

        assertTrue(hsa.remove(key1, key2));
        assertFalse(hsa.remove(key1, key2));
    }