fact.io.hdureader

Class FITS

java.lang.Object

fact.io.hdureader.FITS

public class FITS
extends Object

A FITS object containing all HDUs in a given file. HDUs can be accessed by their name.

FITS f = FITS.fromPath(p) HDU offsets = f.getHDU("ZDrsCellOffsets").orElseThrow(IOException::new); BinTable binTable = offsets.getBinTable();

BinTables can also directly be accessed by name if they exist.

FITS.fromPath(p).getBinTableByName("Events") .ifPresent(binTable -> { //do something with bintable })

Data from the BinTable can be read using the BinTableReader and ZFITSHeapReader classes.

FITS f = new FITS(u); BinTable events = f.getBinTableByName("Events").orElseThrow(IOException::new);

for(OptionalTypesMap p : BinTableReader.forBinTable(events)){ assertTrue(p.containsKey("Data")); }

Created by mackaiver on 03/11/16.

Field Summary

Fields

Modifier and Type	Field and Description
HDU	primaryHDU

Constructor Summary

Constructors

Constructor and Description
FITS(URL url)

Method Summary

Modifier and Type	Method and Description
static FITS	fromFile(File file) Creates a fits instance from a File object without throwing checked exceptions immediately.
static FITS	fromPath(Path path) Creates a fits instance from a path object without throwing checked exceptions immediately.
Optional<BinTable>	getBinTableByName(String hduExtName) Returns the binary data table which is in the HDU by the given name.
Optional<HDU>	getHDU(int hduIndex) This method returns the HDU at given index if it exists.
Optional<HDU>	getHDU(String extname) Extensions may have keyword called EXTNAME.
List<HDU>	getHDUs() Get a list of all HDUs in the fits file.
DataInputStream	getInputStreamForHDUData(HDU hdu) Provides a datastream to the data area of the given hdu.
Map<String,HDU>	getNamedHDUs() Get the a mapping of HDU names to all named HDU objects in the file.

Methods inherited from class java.lang.Object

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

Field Detail

primaryHDU

public HDU primaryHDU

Constructor Detail

FITS

public FITS(URL url)
     throws IOException

Throws:

IOException

Method Detail

fromPath

public static FITS fromPath(Path path)

Creates a fits instance from a path object without throwing checked exceptions immediately.

Parameters:

path - The path to the fits file

Returns:

a FITS object

fromFile

public static FITS fromFile(File file)

Creates a fits instance from a File object without throwing checked exceptions immediately.

Parameters:

file - the fits file

Returns:

a FITS object

getHDU

public Optional<HDU> getHDU(String extname)

Extensions may have keyword called EXTNAME. This method returns the extension with the given name if it exists.

Parameters:

extname - the HDU to get.

Returns:

the HDU with the passed EXTNAME value

getHDU

public Optional<HDU> getHDU(int hduIndex)

This method returns the HDU at given index if it exists.

Parameters:

hduIndex - the HDU to get.

Returns:

the HDU at the given index

getNamedHDUs

public Map<String,HDU> getNamedHDUs()

Get the a mapping of HDU names to all named HDU objects in the file.

Returns:

a map of names to HDUs

getHDUs

public List<HDU> getHDUs()

Get a list of all HDUs in the fits file.

Returns:

a map of names to HDUs

getBinTableByName

public Optional<BinTable> getBinTableByName(String hduExtName)

Returns the binary data table which is in the HDU by the given name. If the HDU exists and it contains a table.

Parameters:

hduExtName - the name of the hdu which contains the bintable

Returns:

the bintable for the specified hdu

getInputStreamForHDUData

public DataInputStream getInputStreamForHDUData(HDU hdu)
                                         throws IOException

Provides a datastream to the data area of the given hdu. This method is useful when reading custom data extensions that are present in the fits file.

Parameters:

hdu - the HDU of interest.

Returns:

a DataInputStream providing data from the data section of the given hdu.

Throws:

IOException - in case the stream cannot be opened