public String asJsonString() {
    try (Writer out = new StringWriter()) {
      new ObjectMapper().writeValue(out, this);
      return out.toString();
    } catch (IOException e) {
      throw new UncheckedIOException("Unable to convert " + this + " to json", e);
    }
  }
Returns the json representation of this object.
@return {@link String} containing a json.
storage-api/src/java/org/apache/hadoop/hive/common/MaterializationSnapshot.java