Package uk.ac.starlink.fits
Class StandardFitsTableSerializer
java.lang.Object
uk.ac.starlink.fits.StandardFitsTableSerializer
- All Implemented Interfaces:
FitsTableSerializer
- Direct Known Subclasses:
VariableFitsTableSerializer
Class which knows how to do the various bits of serializing a StarTable
to FITS BINTABLE format. A normal (row-oriented) organisation of the
data is used.
Array-valued columns are all written as fixed size arrays.
This class does the hard work for FitsTableWriter.
When writing tables that are marked up using the headers defined in
HealpixTableInfo
,
this serializer will attempt to insert FITS headers corresponding
to the HEALPix-FITS convention.
- Author:
- Mark Taylor (Starlink)
- See Also:
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Constructor Summary
ConstructorsConstructorDescriptionStandardFitsTableSerializer
(FitsTableSerializerConfig config, uk.ac.starlink.table.StarTable table) Constructor. -
Method Summary
Modifier and TypeMethodDescriptiongetBadValue
(int icol) Returns the bad value (text of the TNULLnn card), if any, used for a given column.Returns the configuration information for this serializer.int[]
getDimensions
(int icol) Returns the dimensions of the items which will be output for a given column.char
getFormatChar
(int icol) Returns the FITS TFORM letter which describes the type of data output for a given column.Returns header cards suitable for the HDU which will contain the table.protected CardImage[]
getHealpixHeaders
(uk.ac.starlink.table.HealpixTableInfo hpxInfo) Returns FITS headers specific for a table containing a HEALPix map.long
Returns the number of rows which will be output.void
writeData
(DataOutput strm) Writes the HDU data for the table to an output stream.long
writeDataOnly
(DataOutput strm) Writes the table data content without any trailing padding.
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Constructor Details
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StandardFitsTableSerializer
public StandardFitsTableSerializer(FitsTableSerializerConfig config, uk.ac.starlink.table.StarTable table) throws IOException Constructor.- Parameters:
config
- configurationtable
- table to serialize- Throws:
IOException
- if it won't be possible to write the given table
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Method Details
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getConfig
Returns the configuration information for this serializer.- Returns:
- config
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getHeader
Description copied from interface:FitsTableSerializer
Returns header cards suitable for the HDU which will contain the table. Additional metadata and an END marker will be added after these cards, so the returned array must not contain the END card.- Specified by:
getHeader
in interfaceFitsTableSerializer
- Returns:
- header cards
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writeData
Description copied from interface:FitsTableSerializer
Writes the HDU data for the table to an output stream. This is only intended to be called once following creation of this object. Subsequent calls result in undefined behaviour.- Specified by:
writeData
in interfaceFitsTableSerializer
- Parameters:
strm
- destination stream- Throws:
IOException
-
writeDataOnly
Writes the table data content without any trailing padding.- Parameters:
strm
- destination stream- Returns:
- number of bytes written
- Throws:
IOException
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getFormatChar
public char getFormatChar(int icol) Description copied from interface:FitsTableSerializer
Returns the FITS TFORM letter which describes the type of data output for a given column. This is as described by the FITS standard - 'J' for 4-byte integer, 'A' for characters, etc. If the column is not being output,(char)0
will be returned.- Specified by:
getFormatChar
in interfaceFitsTableSerializer
- Parameters:
icol
- column to query- Returns:
- format letter for data in column
icol
, or 0 for a column being skipped
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getDimensions
public int[] getDimensions(int icol) Description copied from interface:FitsTableSerializer
Returns the dimensions of the items which will be output for a given column. This will benull
only if that column is not being output. Otherwise it will be a zero-element array for a scalar, 1-element array for a vector, etc.- Specified by:
getDimensions
in interfaceFitsTableSerializer
- Parameters:
icol
- column to query- Returns:
- dimensions array for data in column
icol
ornull
for a column being skipped
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getBadValue
Description copied from interface:FitsTableSerializer
Returns the bad value (text of the TNULLnn card), if any, used for a given column.- Specified by:
getBadValue
in interfaceFitsTableSerializer
- Parameters:
icol
- column to query- Returns:
- blank value string, or null if there is none or the column is being skipped
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getRowCount
public long getRowCount()Description copied from interface:FitsTableSerializer
Returns the number of rows which will be output.- Specified by:
getRowCount
in interfaceFitsTableSerializer
- Returns:
- row count
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getHealpixHeaders
protected CardImage[] getHealpixHeaders(uk.ac.starlink.table.HealpixTableInfo hpxInfo) throws uk.ac.starlink.table.TableFormatException Returns FITS headers specific for a table containing a HEALPix map. If this method is called the assumption is that the table looks like it should be a HEALPix map of some sort. If there are problems with the metadata that prevent a consistent set of headers from being generated, a TableFormatException with an informative message should be thrown.- Parameters:
hpxInfo
- non-null healpix description- Returns:
- array of FITS headers describing healpix information
- Throws:
uk.ac.starlink.table.TableFormatException
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