legacy/src/main/java/thredds/catalog/crawl/CatalogCrawler.java
public void crawlDirectDatasets(InvDataset ds, CancelTask task, PrintWriter out, Object context, boolean release) {
    boolean isCatRef = (ds instanceof InvCatalogRef);
    if (filter != null && filter.skipAll(ds)) {
      if (isCatRef && release) ((InvCatalogRef) ds).release();
      return;
    }

    if (isCatRef) {
      InvCatalogRef catref = (InvCatalogRef) ds;
      if (out != null)
        out.println(" **CATREF " + catref.getURI() + " (" + ds.getName() + ") ");
      countCatrefs++;
      
      if (!listen.getCatalogRef( catref, context)) {
        if (release) catref.release();
        return;
      }
    }

    // get datasets with data access ("leaves")
    List<InvDataset> dlist = ds.getDatasets();
    List<InvDataset> leaves = new ArrayList<InvDataset>();
    for (InvDataset dds : dlist) {
      if (dds.hasAccess())
        leaves.add(dds);
    }

    if (leaves.size() > 0) {
      if (type == Type.first_direct) {
        InvDataset dds = leaves.get(0);
        listen.getDataset(dds, context);

      } else if (type == Type.random_direct) {
        listen.getDataset(chooseRandom(leaves), context);

      } else if (type == Type.random_direct_middle) {
        listen.getDataset(chooseRandomNotFirstOrLast(leaves), context);

      } else { // do all of them
        for (InvDataset dds : leaves) {
          listen.getDataset(dds, context);
          if ((task != null) && task.isCancel()) break;
        }
      }
    }

    // recurse
      for (InvDataset dds : dlist) {
        if (dds.hasNestedDatasets())
          crawlDirectDatasets(dds, task, out, context, release);
        if ((task != null) && task.isCancel())
          break;
      }

    /* if (out != null) {
     int took = (int) (System.currentTimeMillis() - start);
     out.println(" ** " + ds.getName() + " took " + took + " msecs\n");
   } */

    if (ds instanceof InvCatalogRef && release) {
      InvCatalogRef catref = (InvCatalogRef) ds;
      catref.release();
    }

  }
public void crawlDirectDatasets(InvDataset ds, CancelTask task, PrintWriter out, Object context, boolean release) {
    boolean isCatRef = (ds instanceof InvCatalogRef);
    if (filter != null && filter.skipAll(ds)) {
      if (isCatRef && release) ((InvCatalogRef) ds).release();
      return;
    }

    if (isCatRef) {
      InvCatalogRef catref = (InvCatalogRef) ds;
      if (out != null)
        out.println(" **CATREF " + catref.getURI() + " (" + ds.getName() + ") ");
      countCatrefs++;
      
      if (!listen.getCatalogRef( catref, context)) {
        if (release) catref.release();
        return;
      }
    }

    // get datasets with data access ("leaves")
    List<InvDataset> dlist = ds.getDatasets();
    List<InvDataset> leaves = new ArrayList<InvDataset>();
    for (InvDataset dds : dlist) {
      if (dds.hasAccess())
        leaves.add(dds);
    }

    if (leaves.size() > 0) {
      if (type == Type.first_direct) {
        InvDataset dds = leaves.get(0);
        listen.getDataset(dds, context);

      } else if (type == Type.random_direct) {
        listen.getDataset(chooseRandom(leaves), context);

      } else if (type == Type.random_direct_middle) {
        listen.getDataset(chooseRandomNotFirstOrLast(leaves), context);

      } else { // do all of them
        for (InvDataset dds : leaves) {
          listen.getDataset(dds, context);
          if ((task != null) && task.isCancel()) break;
        }
      }
    }

    // recurse
      for (InvDataset dds : dlist) {
        if (dds.hasNestedDatasets())
          crawlDirectDatasets(dds, task, out, context, release);
        if ((task != null) && task.isCancel())
          break;
      }

    /* if (out != null) {
     int took = (int) (System.currentTimeMillis() - start);
     out.println(" ** " + ds.getName() + " took " + took + " msecs\n");
   } */

    if (ds instanceof InvCatalogRef && release) {
      InvCatalogRef catref = (InvCatalogRef) ds;
      catref.release();
    }

  }
Crawl this dataset recursively. Only send back direct datasets

@param ds   the dataset
@param task user can cancel the task (may be null)
@param out  send status messages to here (may be null)
@param context caller can pass this object in (used for thread safety)