uk.ac.starlink.table
Class EmptyStarTable

java.lang.Object
  extended by uk.ac.starlink.table.WrapperStarTable
      extended by uk.ac.starlink.table.EmptyStarTable
All Implemented Interfaces:
StarTable

public class EmptyStarTable
extends WrapperStarTable

A wrapper table which has the same metadata as its base table, but no rows.

Since:
5 Aug 2004

Field Summary
 
Fields inherited from class uk.ac.starlink.table.WrapperStarTable
baseTable
 
Constructor Summary
EmptyStarTable()
          Creates a new empty table with no columns, no rows and no parameters.
EmptyStarTable(StarTable baseTable)
          Creates a new empty table with metadata taken from an existing one.
 
Method Summary
 Object getCell(long lrow, int icol)
          Returns the contents of a given table cell.
 Object[] getRow(long lrow)
          Returns the contents of a given table row.
 long getRowCount()
          Returns the number of rows in this table, if known.
 RowSequence getRowSequence()
          Returns an object which can iterate over all the rows in the table sequentially.
 boolean isRandom()
          Indicates whether random access is provided by this table.
 
Methods inherited from class uk.ac.starlink.table.WrapperStarTable
checkedLongToInt, getBaseTable, getColumnAuxDataInfos, getColumnCount, getColumnInfo, getName, getParameterByName, getParameters, getURL, setName, setParameter, setURL, toString
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

EmptyStarTable

public EmptyStarTable(StarTable baseTable)
Creates a new empty table with metadata taken from an existing one.

Parameters:
baseTable - base table

EmptyStarTable

public EmptyStarTable()
Creates a new empty table with no columns, no rows and no parameters.

Method Detail

isRandom

public boolean isRandom()
Description copied from interface: StarTable
Indicates whether random access is provided by this table. Only if the result is true may the StarTable.getRow(long) and StarTable.getCell(long, int) methods be used.

Specified by:
isRandom in interface StarTable
Overrides:
isRandom in class WrapperStarTable
Returns:
true if table random access methods are available

getRowCount

public long getRowCount()
Description copied from interface: StarTable
Returns the number of rows in this table, if known. If the number of rows cannot be (easily) determined, a value of -1 will be returned.

Specified by:
getRowCount in interface StarTable
Overrides:
getRowCount in class WrapperStarTable
Returns:
the number of rows, or -1

getCell

public Object getCell(long lrow,
                      int icol)
Description copied from interface: StarTable
Returns the contents of a given table cell. The class of the returned object should be the same as, or a subclass of, the class returned by getColumnInfo(icol).getContentClass().

Specified by:
getCell in interface StarTable
Overrides:
getCell in class WrapperStarTable
Parameters:
lrow - the index of the cell's row
icol - the index of the cell's column
Returns:
the contents of this cell

getRow

public Object[] getRow(long lrow)
Description copied from interface: StarTable
Returns the contents of a given table row. The returned value is equivalent to an array formed of all the objects returned by getCell(irow,icol) for all the columns icol in sequence.

Specified by:
getRow in interface StarTable
Overrides:
getRow in class WrapperStarTable
Parameters:
lrow - the index of the row to retrieve
Returns:
an array of the objects in each cell in row irow

getRowSequence

public RowSequence getRowSequence()
Description copied from interface: StarTable
Returns an object which can iterate over all the rows in the table sequentially.

Specified by:
getRowSequence in interface StarTable
Overrides:
getRowSequence in class WrapperStarTable
Returns:
an object providing sequential access to the table data

Copyright © 2004 CLRC: Central Laboratory of the Research Councils. All rights reserved.