uk.ac.starlink.oldfits

Class FitsStarTable

java.lang.Object

uk.ac.starlink.table.AbstractStarTable

uk.ac.starlink.table.RandomStarTable

uk.ac.starlink.oldfits.FitsStarTable

All Implemented Interfaces:

Closeable, AutoCloseable, StarTable

public class FitsStarTable
extends RandomStarTable

An implementation of the StarTable interface which uses FITS TABLE or BINTABLE extensions.

This implementation uses the table handling in the nom.tam.fits package. I think that performance could be considerably improved by rewriting the table access from scratch. The reason for this is largely that the nom.tam.fits classes do a lot of wrapping of values in (perhaps multi-dimensional) arrays, which is not for our purposes necessary. Such a re-implementation would take a bit of effort unfortunately.

This class should only be used for TABLE extension (that is ASCII table) HDUs. The BintableStarTable class is much more efficient for BINTTABLE extensions (binary table) HDUs.

Author:

Mark Taylor (Starlink)

Constructor Summary

Constructors

Constructor and Description
FitsStarTable(TableHDU thdu) Constructs a FitsStarTable object from a FITS TableHDU object.

Method Summary

Modifier and Type	Method and Description
Object	getCell(long lrow, int icol) Implementations of this method must be safe for concurrent calls from multiple threads.
List<ValueInfo>	getColumnAuxDataInfos() Goes through the table columns (ColumnInfo objects) and picks out all the AuxData items which exist, generalising where necessary and returning a union of them in alphabetical order by name.
int	getColumnCount() Returns the number of columns in this table.
ColumnInfo	getColumnInfo(int icol) Returns the object describing the data in a given column.
Object[]	getRow(long lrow) The AbstractStarTable implementation of this method constructs a row by repeated invocation of AbstractStarTable.getCell(long, int).
long	getRowCount() Implementations must supply a non-negative return value.

Methods inherited from class uk.ac.starlink.table.RandomStarTable

getRowAccess, getRowSequence, isRandom

Methods inherited from class uk.ac.starlink.table.AbstractStarTable

checkedLongToInt, close, getName, getParameters, getRowSplittable, getURL, setName, setParameters, setURL

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface uk.ac.starlink.table.StarTable

getParameterByName, setParameter

Constructor Detail

FitsStarTable

public FitsStarTable(TableHDU thdu)
              throws IOException

Constructs a FitsStarTable object from a FITS TableHDU object.

Parameters:

thdu - a TableHDU object containing data

Throws:

IOException

Method Detail

getRowCount

public long getRowCount()

Description copied from class: RandomStarTable

Implementations must supply a non-negative return value.

Specified by:

getRowCount in interface StarTable

Specified by:

getRowCount in class RandomStarTable

Returns:

the number of rows in the table

getColumnCount

public int getColumnCount()

Description copied from interface: StarTable

Returns the number of columns in this table.

Specified by:

getColumnCount in interface StarTable

Specified by:

getColumnCount in class AbstractStarTable

Returns:

the number of columns

getColumnInfo

public ColumnInfo getColumnInfo(int icol)

Description copied from interface: StarTable

Returns the object describing the data in a given column.

Specified by:

getColumnInfo in interface StarTable

Specified by:

getColumnInfo in class AbstractStarTable

Parameters:

icol - the column for which header information is required

Returns:

a ValueInfo object for column icol

getColumnAuxDataInfos

public List<ValueInfo> getColumnAuxDataInfos()

Description copied from class: AbstractStarTable

Goes through the table columns (ColumnInfo objects) and picks out all the AuxData items which exist, generalising where necessary and returning a union of them in alphabetical order by name. Subclasses should override this if they can do better, for instance providing an order for the keys.

Specified by:

getColumnAuxDataInfos in interface StarTable

Overrides:

getColumnAuxDataInfos in class AbstractStarTable

Returns:

a list of all the auxiliary metadata ValueInfo items which in fact crop up in column metadata

See Also:

DefaultValueInfo.getAuxData()

getCell

public Object getCell(long lrow,
                      int icol)
               throws IOException

Description copied from class: RandomStarTable

Implementations of this method must be safe for concurrent calls from multiple threads.

Specified by:

getCell in interface StarTable

Specified by:

getCell in class RandomStarTable

Parameters:

lrow - the index of the cell's row

icol - the index of the cell's column

Returns:

the contents of this cell

Throws:

IOException - if there is an error reading the data

getRow

public Object[] getRow(long lrow)
                throws IOException

Description copied from class: AbstractStarTable

The AbstractStarTable implementation of this method constructs a row by repeated invocation of AbstractStarTable.getCell(long, int).

Specified by:

getRow in interface StarTable

Overrides:

getRow in class AbstractStarTable

Parameters:

lrow - the index of the row to retrieve

Returns:

an array of the objects in each cell in row irow

Throws:

IOException - if there is an error reading the data