Package uk.ac.starlink.fits

Class StandardFitsTableSerializer

  • All Implemented Interfaces:
    FitsTableSerializer
    Direct Known Subclasses:
    VariableFitsTableSerializer
    public class StandardFitsTableSerializer
extends java.lang.Object
implements FitsTableSerializer
    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.
    Author:
    Mark Taylor (Starlink)

    • Constructor Summary

      Constructors 
      Constructor Description
      StandardFitsTableSerializer​(uk.ac.starlink.table.StarTable table, boolean allowSignedByte, WideFits wide)
      Constructs a serializer to write a given StarTable, with explicit instruction about how to write byte-type columns data.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      java.lang.String getBadValue​(int icol)
      Returns the bad value (text of the TNULLnn card), if any, used for a given column.
      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.
      nom.tam.fits.Header getHeader()
      Returns a header suitable for the HDU which will contain the table.
      long getRowCount()
      Returns the number of rows which will be output.
      void writeData​(java.io.DataOutput strm)
      Writes the HDU data for the table to an output stream.

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • StandardFitsTableSerializer

        public StandardFitsTableSerializer​(uk.ac.starlink.table.StarTable table,
                                   boolean allowSignedByte,
                                   WideFits wide)
                            throws java.io.IOException
        Constructs a serializer to write a given StarTable, with explicit instruction about how to write byte-type columns data. Since FITS bytes are unsigned (unlike, for instance, java bytes), they can cause trouble in some circumstances, so avoiding writing them may sometimes help.
        Parameters:
        table - the table to be written
        allowSignedByte - if true, bytes written as FITS signed bytes (TZERO=-128), if false bytes written as signed shorts
        wide - convention for representing over-wide tables; null to avoid this convention
        Throws:
        java.io.IOException - if it won't be possible to write the given table

    • Method Detail

      • getHeader

        public nom.tam.fits.Header getHeader()
                              throws nom.tam.fits.HeaderCardException
        Description copied from interface: FitsTableSerializer
        Returns a header suitable for the HDU which will contain the table.
        Specified by:
        getHeader in interface FitsTableSerializer
        Returns:
        header object
        Throws:
        nom.tam.fits.HeaderCardException

      • writeData

        public void writeData​(java.io.DataOutput strm)
               throws java.io.IOException
        Description copied from interface: FitsTableSerializer
        Writes the HDU data for the table to an output stream.
        Specified by:
        writeData in interface FitsTableSerializer
        Parameters:
        strm - destination stream
        Throws:
        java.io.IOException

      • 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 interface FitsTableSerializer
        Parameters:
        icol - column to query
        Returns:
        format letter for data in column icol, or 0 for a column being skipped

      • 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 be null 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 interface FitsTableSerializer
        Parameters:
        icol - column to query
        Returns:
        dimensions array for data in column icol or null for a column being skipped

      • getBadValue

        public java.lang.String getBadValue​(int icol)
        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 interface FitsTableSerializer
        Parameters:
        icol - column to query
        Returns:
        blank value string, or null if there is none or the column is being skipped