private final ArrayList<HStoreFile> getLevel0Copy() {
      if (this.level0Files == null) {
        this.level0Files = new ArrayList<>(StripeStoreFileManager.this.state.level0Files);
      }
      return this.level0Files;
    }
Returns A lazy L0 copy from current state.
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StripeStoreFileManager.java