Java Code Examples for org.apache.avro.io.parsing.Symbol#MAP_KEY_MARKER

/**
 * Read a string from the current location in parser.
 *
 * <p>This method differs from the original JsonDecoder by serializing all
 * structures captured by the current token into a JSON string. This enables
 * consistent behavior for handling variant types (e.g. field that can be a
 * boolean and a string) and for under-specified schemas.
 *
 * <p>This encoding is lossy because JSON strings are conflated with standard
 * strings. Consider the case where a number is decoded into a string. To
 * convert this Avro file back into the original JSON document, the encoder
 * must parse all strings as JSON and inline them into the tree. Now, if the
 * original JSON represents a JSON object as a string (e.g. `{"payload":
 * "{\"foo\":\"bar\"}"`), then the encoder will generate a new object that is
 * different from the original.
 *
 * <p>There are a few ways to avoid this if it is undesirable. One way is to use
 * a binary encoding for the JSON data such as BSON or base64. A second is to
 * normalize documents to avoid nested JSON encodings and to specify a schema
 * explictly to guide the proper typing.
 */
@Override
public String readString() throws IOException {
  parser.advance(Symbol.STRING);
  if (parser.topSymbol() == Symbol.MAP_KEY_MARKER) {
    parser.advance(Symbol.MAP_KEY_MARKER);
    assertCurrentToken(JsonToken.FIELD_NAME, "map-key");
  }

  String result = null;
  if (in.getCurrentToken() == JsonToken.VALUE_STRING
      || in.getCurrentToken() == JsonToken.FIELD_NAME) {
    result = in.getValueAsString();
  } else {
    // Does this create excessive garbage collection?
    TokenBuffer buffer = new TokenBuffer(in);
    buffer.copyCurrentStructure(in);
    result = mapper.readTree(buffer.asParser()).toString();
    buffer.close();
  }
  in.nextToken();
  return result;
}
 

@Override
public String readString() throws IOException {
    advance(Symbol.STRING);
    if (parser.topSymbol() == Symbol.MAP_KEY_MARKER) {
        parser.advance(Symbol.MAP_KEY_MARKER);
            if (in.getCurrentToken() != JsonToken.FIELD_NAME) {
                throw error("map-key");
            }
        } else {
            if (in.getCurrentToken() != JsonToken.VALUE_STRING) {
            throw error("string");
        }
    }
    String result = in.getText();
    in.nextToken();
    return result;
}
 

@Override
public void skipString() throws IOException {
    advance(Symbol.STRING);
    if (parser.topSymbol() == Symbol.MAP_KEY_MARKER) {
        parser.advance(Symbol.MAP_KEY_MARKER);
        if (in.getCurrentToken() != JsonToken.FIELD_NAME) {
            throw error("map-key");
        }
    } else {
          if (in.getCurrentToken() != JsonToken.VALUE_STRING) {
              throw error("string");
          }
    }
    in.nextToken();
}