BitSet implements Serializable, Cloneable { @Override public BitSet clone() { return new BitSet(bits); } BitSet(int numBits); private  BitSet(long[] bits); @Override BitSet clone(); @Override String toString();  }
@Test public void testClone() { BitSet bitSet = new BitSet(NUM_BITS); bitSet.set(NUM_BITS-1); bitSet = bitSet.clone(); assertTrue(bitSet.get(NUM_BITS-1)); }