Class SequenceReader

Method Details

• add

  public SequenceReader add(DataReader reader)

  Appends a reader to the sequence; must be called before open().

• addExceptionProperties

  public DataException addExceptionProperties(DataException exception)

  Description copied from class: Endpoint

  Adds this endpoint's current state to a DataException. Since this method is called whenever an exception is thrown, subclasses should override it to add their specific information.

  Overrides:

  addExceptionProperties in class DataReader

• getCount

  public int getCount()

  Returns the number of readers in the sequence.

• remove

  public SequenceReader remove(DataReader reader)

  Takes a reader out of the sequence; must be called before open().

• removeAllDataReader

  public SequenceReader removeAllDataReader()

  Empties the sequence; must be called before open().

• get

  public DataReader get(int index)

  Returns the reader at the given 0-based position in the sequence.

• open

  public void open() throws DataException

  Description copied from class: DataEndpoint

  Makes this endpoint ready for reading or writing.

  Overrides:

  open in class DataEndpoint

  Throws:

  DataException

• available

  public int available()

  Description copied from class: DataReader

  Returns the number of records that can probably be read without blocking.

  Overrides:

  available in class DataReader

• close

  public void close() throws DataException

  Description copied from class: DataEndpoint

  Indicates that this endpoint has finished reading or writing.

  Overrides:

  close in class DataEndpoint

  Throws:

  DataException

• readImpl

  protected Record readImpl() throws Throwable

  Description copied from class: DataReader

  Overridden by subclasses to read the next record from this DataReader. The default implementation of DataReader.read() now insures that this method will not be called again after it returns a null.

  If no record is available, null will be returned.

  Contract for subclasses (see also docs/authoring/DataReader.md):

  • Return null exactly once to signal end-of-stream.
  • Do not call this method directly — DataReader.read() is the template method that wraps exceptions, increments the record count, and tracks lineage.
  • Do not call DataEndpoint.incrementRecordCount() here; DataReader.read() already does.
  • Throw raw exceptions; DataReader.read() wraps them via exception(throwable).

  Specified by:

  readImpl in class DataReader

  Throws:

  Throwable