public void clear() {         // Smack a new empty table down
    CHM newchm = new CHM(this,new ConcurrentAutoTable(),MIN_SIZE_LOG);
    while( !CAS(_chm_offset,_chm,newchm) ) { /*Spin until the clear works*/}
    CAS(_val_1_offset,_val_1,TOMBSTONE);
  }
Removes all of the mappings from this map.
jctools-core/src/main/java/org/jctools/maps/NonBlockingHashMapLong.java