### Question:
MutableLinearProbeLongHashSet extends AbstractLinearProbeLongHashSet implements MutableLongSet, Resource { @Override public LongSet freeze() { frozen = true; final FrozenCopy frozen = new FrozenCopy(); frozenCopies.put( memory, frozen ); return frozen; } MutableLinearProbeLongHashSet( MemoryAllocator allocator ); @Override boolean add( long element ); @Override boolean addAll( long... elements ); @Override boolean addAll( LongIterable elements ); @Override boolean remove( long element ); @Override boolean removeAll( LongIterable elements ); @Override boolean removeAll( long... elements ); @Override boolean retainAll( LongIterable elements ); @Override boolean retainAll( long... source ); @Override void clear(); @Override MutableLongIterator longIterator(); @Override void close(); @Override MutableLongSet tap( LongProcedure procedure ); @Override MutableLongSet with( long element ); @Override MutableLongSet without( long element ); @Override MutableLongSet withAll( LongIterable elements ); @Override MutableLongSet withoutAll( LongIterable elements ); @Override MutableLongSet asUnmodifiable(); @Override MutableLongSet asSynchronized(); @Override LongSet freeze(); @Override ImmutableLongSet toImmutable();  }### Answer:
@Test void freeze() { set.addAll( 1, 2, 3, 100, 200, 300 ); final LongSet frozen = set.freeze(); assertEquals( set, frozen ); assertEquals( 6, set.size() ); assertEquals( 6, frozen.size() ); set.removeAll( 1, 100 ); assertNotEquals( set, frozen ); assertEquals( 4, set.size() ); assertEquals( 6, frozen.size() ); }