LongBitMask extends SingleLongBitMask implements BitMask { @Override public BitMask set(int index) { if (index >= 64) { return BitMask.Factory.getEmpty(index+1).setAll(this).set(index); } this.mask = this.mask | (1L << index); return this; } LongBitMask();  LongBitMask(long mask); @Override BitMask set(int index); @Override BitMask setAll(BitMask mask); @Override BitMask reset(int index); @Override BitMask resetAll(BitMask mask); @Override boolean isSet(int index); @Override boolean isAllSet(); @Override boolean isEmpty(); @Override boolean intersects(BitMask mask); long asLong(); @Override LongBitMask clone(); @Override String getInstancingStatement();  }
@Test public void testSet() { Assert.assertEquals("1", new LongBitMask().set(0).toString()); Assert.assertEquals("2", new LongBitMask().set(1).toString()); Assert.assertEquals("0, 2", new LongBitMask().set(65).toString()); }