Package uk.ac.starlink.table

Class AccessRowSequence

java.lang.Object
uk.ac.starlink.table.AccessRowSequence
All Implemented Interfaces:
Closeable, AutoCloseable, RowData, RowSequence, uk.ac.starlink.util.Sequence
public class AccessRowSequence extends Object implements RowSequence
RowSequence implementation based on a RowAccess.
Since:
24 Jul 2020
Author:
Mark Taylor

  • Constructor Details

    • AccessRowSequence

      public AccessRowSequence(RowAccess racc, long nrow)
      Constructor.
      Parameters:
      racc - row access providing data access
      nrow - number of rows

  • Method Details

    • next

      public boolean next() throws IOException
      Description copied from interface: RowSequence
      Attempts to advance the current row to the next one. If true is returned the attempt has been successful, and if false is returned there are no more rows in this sequence. Since the initial position of a RowSequence is before the first row, this method must be called before current row data can be accessed using the RowSequence.getCell(int) or RowSequence.getRow() methods.
      Specified by:
      next in interface RowSequence
      Specified by:
      next in interface uk.ac.starlink.util.Sequence
      Returns:
      true iff this sequence has been advanced to the next row
      Throws:
      IOException - if there is some error

    • getCell

      public Object getCell(int icol) throws IOException
      Description copied from interface: RowSequence
      Returns the contents of a cell in the current row. The class of the returned object should be the same as, or a subclass of, the class returned by getColumnInfo(icol).getContentClass(). An unchecked exception will be thrown if there is no current row (next has not yet been called).
      Specified by:
      getCell in interface RowData
      Specified by:
      getCell in interface RowSequence
      Parameters:
      icol - column index
      Returns:
      the contents of cell icol in the current row
      Throws:
      IOException - if there is an error reading the data

    • getRow

      public Object[] getRow() throws IOException
      Description copied from interface: RowSequence
      Returns the contents of the current table row, as an array with the same number of elements as there are columns in this table. An unchecked exception will be thrown if there is no current row (next has not yet been called).
      Specified by:
      getRow in interface RowData
      Specified by:
      getRow in interface RowSequence
      Returns:
      an array of the objects in each cell in row irow
      Throws:
      IOException - if there is an error reading the data

    • close

      public void close() throws IOException
      Description copied from interface: RowSequence
      Indicates that this sequence will not be required any more. This should release resources associated with this object. The effect of calling any of the other methods following a close is undefined.
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Specified by:
      close in interface RowSequence
      Throws:
      IOException

    • createInstance

      public static AccessRowSequence createInstance(StarTable table) throws IOException
      Constructs an AccessRowSequence based on a given table.
      Parameters:
      table - table
      Returns:
      new row access
      Throws:
      IOException