docs: protected void overwriteOldEntry(Entry newEntry) {
          assert (this.getBuffer().isEmpty());
          assert (newEntry.getBuffer().isEmpty());
          this.data.overwriteOldCluster(newEntry.data);
          newEntry.setParentEntry(this.parentEntry);
          if (newEntry.getChild()!=null)
          for (Entry e : newEntry.getChild().getEntries())
          	e.setParentEntry(this);
          //this.setParentEntry(newEntry.getParentEntry());
          this.child=newEntry.child;
      }