src/main/java/com/googlecode/javaewah/datastructure/ImmutableBitSet.java
public BitSet asBitSet() {
  	BitSet bs = new BitSet(this.size());
  	this.data.rewind();
  	this.data.get(bs.data, 0, bs.data.length);
		return bs;
  }
public BitSet asBitSet() {
  	BitSet bs = new BitSet(this.size());
  	this.data.rewind();
  	this.data.get(bs.data, 0, bs.data.length);
		return bs;
  }
Get a copy of this ImmutableBitSet as a mutable BitSet.
@return a copy