### Question:
Roaring64Bitmap implements Externalizable, LongBitmapDataProvider { public boolean runOptimize() { boolean hasChanged = false; ContainerIterator containerIterator = highLowContainer.containerIterator(); while (containerIterator.hasNext()) { Container container = containerIterator.next(); Container freshContainer = container.runOptimize(); if (freshContainer instanceof RunContainer) { hasChanged = true; containerIterator.replace(freshContainer); } } return hasChanged; } Roaring64Bitmap(); void addInt(int x); @Override void addLong(long x); @Override long getLongCardinality(); int getIntCardinality(); @Override long select(final long j); Iterator<Long> iterator(); @Override void forEach(final LongConsumer lc); @Override long rankLong(long id); void or(final Roaring64Bitmap x2); void xor(final Roaring64Bitmap x2); void and(final Roaring64Bitmap x2); void andNot(final Roaring64Bitmap x2); @Override void writeExternal(ObjectOutput out); @Override void readExternal(ObjectInput in); @Override String toString(); @Override LongIterator getLongIterator(); @Override boolean contains(long x); @Override int getSizeInBytes(); @Override long getLongSizeInBytes(); @Override boolean isEmpty(); @Override ImmutableLongBitmapDataProvider limit(long x); boolean runOptimize(); @Override void serialize(DataOutput out); void serialize(ByteBuffer byteBuffer); void deserialize(DataInput in); void deserialize(ByteBuffer in); @Override long serializedSizeInBytes(); void clear(); @Override long[] toArray(); static Roaring64Bitmap bitmapOf(final long... dat); void add(long... dat); void add(final long rangeStart, final long rangeEnd); @Override LongIterator getReverseLongIterator(); @Override void removeLong(long x); @Override void trim(); @Override int hashCode(); @Override boolean equals(Object obj); void flip(final long x); @Override Roaring64Bitmap clone();  }### Answer:
@Test public void testRunOptimize() { Roaring64Bitmap map = new Roaring64Bitmap(); map.addLong(123); map.addLong(234); map.runOptimize(); }