code: public void readTable() {
      // [START bigtable_hw_scan_all_veneer]
      try {
        System.out.println("\nReading the entire table");
        Query query = Query.create(tableId);
        ServerStream<Row> rowStream = dataClient.readRows(query);
        for (Row r : rowStream) {
          System.out.println("Row Key: " + r.getKey().toStringUtf8());
          for (RowCell cell : r.getCells()) {
            System.out.printf(
                "Family: %s    Qualifier: %s    Value: %s%n",
                cell.getFamily(), cell.getQualifier().toStringUtf8(), cell.getValue().toStringUtf8());
          }
        }
      } catch (NotFoundException e) {
        System.err.println("Failed to read a non-existent table: " + e.getMessage());
      }
      // [END bigtable_hw_scan_all_veneer]
    }
docs: Demonstrates how to read an entire table.