cdm/src/main/java/ucar/nc2/dataset/NetcdfDataset.java
@Override
  public synchronized void close() throws java.io.IOException {
    if (agg != null) {
      agg.persistWrite(); // LOOK  maybe only on real close ??
      agg.close();
    }

    if (cache != null) {
      //unlocked = true;
      if (cache.release(this)) return;
    }

    if (orgFile != null) orgFile.close();
    orgFile = null;
  }
@Override
  public synchronized void close() throws java.io.IOException {
    if (agg != null) {
      agg.persistWrite(); // LOOK  maybe only on real close ??
      agg.close();
    }

    if (cache != null) {
      //unlocked = true;
      if (cache.release(this)) return;
    }

    if (orgFile != null) orgFile.close();
    orgFile = null;
  }
Close all resources (files, sockets, etc) associated with this dataset.
If the underlying file was acquired, it will be released, otherwise closed.