nom.tam.fits
Class BinaryTable

java.lang.Object
  nom.tam.fits.Data
      nom.tam.fits.BinaryTable

public class BinaryTable

extends Data

This class defines the methods for accessing FITS binary table data.

Field Summary

(package private) Vector	columns The columns of data in the binary table.
(package private) int[][]	dimens The dimensions of each column.
(package private) byte[]	hashArea This is the area in which variable length column data lives.
(package private) int	hashPtr Pointer to the next available byte in the hashArea.
(package private) Object[]	modelRow An example of the structure of a row
(package private) int[]	sizes The sizes of each column (in number of entries per row)
(package private) ColumnTable	table Where the data is actually stored.

Fields inherited from class nom.tam.fits.Data

dataArray

Constructor Summary

BinaryTable()
Create a null binary table data segment.

BinaryTable(Header myHeader)
Create a binary table from given header information.

BinaryTable(Object[][] data)
Create a binary table from existing data in row order.

Method Summary

void	addColumn(Object[] o) Add a column to the end of a table.
void	addFlattenedColumn(Object o, int[] dims) Add a column where the data is already flattened.
void	addRow(Object[] o) Add a row at the end of the table.
Column	addVarData(Object[] data) Add a variable length column to the data.
protected void	expandHashArea(int need) This routine makes sure the hash area is large enough to fill a given request.
Class[]	getBases()
Object[]	getColumn(int col) Get a given column
int[][]	getDimens()
Object	getElement(int i, int j) Get a particular element from the table.
Object	getFlattenedColumn(int col) Get a column in flattened format.
int	getHeapSize()
int	getNcol() Get the number of columns in the table.
int	getNrow() Get the number of rows in the table
Object[]	getRow(int row) Get a given row
int[]	getSizes()
int	getTrueSize() Get the size of the data in the HDU sans padding.
char[]	getTypes()
Object	getVarData(int col, Class baseClass, boolean complex) Get the data from a variable length column as a two-d primitive array.
void	read(BufferedDataInputStream i) Read a data array into the current object and if needed position to the beginning of the next FITS block.
protected void	readTrueData(BufferedDataInputStream i) Read in the actual data portion.
void	setColumn(int col, Object[] xcol) Replace a column in the table.
void	setElement(int i, int j, Object o) Replace a single element within the table.
void	setFlattenedColumn(int col, Object data) Set a column with the data already flattened.
void	setRow(int row, Object[] data) Replace a row in the table.
protected int	useModelRow(Object[] model, int nrow) Use an example row to determine what the table should look like.
protected boolean	validColumn(int j) Check if the column number is valid.
protected boolean	validRow(int i) Check to see if this is a valid row.
void	write(BufferedDataOutputStream os) Write the data -- including any buffering needed
protected void	writeTrueData(BufferedDataOutputStream o) Write the data including any hash data.

Methods inherited from class nom.tam.fits.Data

getData, getPaddedSize, getPadding

Methods inherited from class java.lang.Object

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

Field Detail

hashArea

byte[] hashArea

This is the area in which variable length column data lives.

hashPtr

int hashPtr

Pointer to the next available byte in the hashArea.

columns

Vector columns

The columns of data in the binary table.

sizes

int[] sizes

The sizes of each column (in number of entries per row)

dimens

int[][] dimens

The dimensions of each column.

modelRow

Object[] modelRow

An example of the structure of a row

table

ColumnTable table

Where the data is actually stored.

Constructor Detail

BinaryTable

public BinaryTable()
            throws FitsException

Create a null binary table data segment.

BinaryTable

public BinaryTable(Header myHeader)
            throws FitsException

Create a binary table from given header information.

BinaryTable

public BinaryTable(Object[][] data)
            throws FitsException

Create a binary table from existing data in row order.

Parameters:

data - The data used to initialize the binary table.

Method Detail

useModelRow

protected int useModelRow(Object[] model,
                          int nrow)

Use an example row to determine what the table should look like.

Parameters:

model - An example of a row. Each element of model should have the structure of the corresponding element of the row.

nrow - The number of rows in the table.

Returns:

The size of the table in bytes.

getRow

public Object[] getRow(int row)
                throws FitsException

Get a given row

Parameters:

row - The index of the row to be returned.

Returns:

A row of data.

Throws:

FitsException

setRow

public void setRow(int row,
                   Object[] data)
            throws FitsException

Replace a row in the table.

Parameters:

row - The index of the row to be replaced.

data - The new values for the row.

Throws:

FitsException - Thrown if the new row cannot match the existing data.

setColumn

public void setColumn(int col,
                      Object[] xcol)
               throws FitsException

Replace a column in the table.

Parameters:

col - The index of the column to be replaced.

xcol - The new data for the column

Throws:

FitsException - Thrown if the data does not match the current column description.

setFlattenedColumn

public void setFlattenedColumn(int col,
                               Object data)
                        throws FitsException

Set a column with the data already flattened.

Parameters:

col - The index of the column to be replaced.

data - The new data array. This should be a one-d primitive array.

Throws:

FitsException - Thrown if the type of length of the replacement data differs from the original.

getColumn

public Object[] getColumn(int col)
                   throws FitsException

Get a given column

Parameters:

col - The index of the column.

Throws:

FitsException

getFlattenedColumn

public Object getFlattenedColumn(int col)
                          throws FitsException

Get a column in flattened format. For large tables getting a column in standard format can be inefficient because a separate object is needed for each row. Leaving the data in flattened format means that only a single object is created.

Parameters:

col -

Throws:

FitsException

getElement

public Object getElement(int i,
                         int j)
                  throws FitsException

Get a particular element from the table.

Parameters:

i - The row of the element.

j - The column of the element.

Throws:

FitsException

addRow

public void addRow(Object[] o)
            throws FitsException

Add a row at the end of the table.

Parameters:

o - An array of objects instantiating the data. These should have the same structure as any existing rows.

Throws:

FitsException

addColumn

public void addColumn(Object[] o)
               throws FitsException

Add a column to the end of a table.

Parameters:

o - An array of identically structured objects with the same number of elements as other columns in the table.

Throws:

FitsException

addFlattenedColumn

public void addFlattenedColumn(Object o,
                               int[] dims)
                        throws FitsException

Add a column where the data is already flattened.

Parameters:

o - The new column data. This should be a one-dimensional primitive array.

Throws:

FitsException

getNrow

public int getNrow()

Get the number of rows in the table

getNcol

public int getNcol()

Get the number of columns in the table.

validRow

protected boolean validRow(int i)

Check to see if this is a valid row.

Parameters:

i - The Java index (first=0) of the row to check.

validColumn

protected boolean validColumn(int j)

Check if the column number is valid.

Parameters:

j - The Java index (first=0) of the column to check.

setElement

public void setElement(int i,
                       int j,
                       Object o)
                throws FitsException

Replace a single element within the table.

Parameters:

i - The row of the data.

j - The column of the data.

o - The replacement data.

Throws:

FitsException

expandHashArea

protected void expandHashArea(int need)

This routine makes sure the hash area is large enough to fill a given request. If not it reallocates the hash area, and copies the old data into the new area.

Parameters:

need - The number of bytes needed for the current hash area request.

writeTrueData

protected void writeTrueData(BufferedDataOutputStream o)
                      throws FitsException

Write the data including any hash data.

Overrides:

writeTrueData in class Data

Parameters:

o - The output stream.

Throws:

FitsException

read

public void read(BufferedDataInputStream i)
          throws FitsException

Description copied from class: Data

Read a data array into the current object and if needed position to the beginning of the next FITS block.

Overrides:

read in class Data

Parameters:

i - The input data stream

Throws:

FitsException

readTrueData

protected void readTrueData(BufferedDataInputStream i)
                     throws FitsException

Description copied from class: Data

Read in the actual data portion. This method needs to be overriden for ASCII tables and for binary tables with variable length data.

Overrides:

readTrueData in class Data

Parameters:

i - The input stream.

Throws:

FitsException

getTrueSize

public int getTrueSize()

Get the size of the data in the HDU sans padding.

Overrides:

getTrueSize in class Data

addVarData

public Column addVarData(Object[] data)
                  throws FitsException

Add a variable length column to the data.

Parameters:

data - The data comprising the variable length column. This should be a two dimensional primitive array (3D for complex data). Note that it is declared as a one dimensional object array to make access convenient. Any 2-d array can be cast to a 1-d array of objects.

Returns:

A column describing the variable format data. This column can then be added to the table using other functions.

Throws:

FitsException

getVarData

public Object getVarData(int col,
                         Class baseClass,
                         boolean complex)
                  throws FitsException

Get the data from a variable length column as a two-d primitive array.

Parameters:

col - The index of the column to be returned.

baseClass - The base class of the array. It should be one of the primitive types, e.g, Integer.TYPE.

Throws:

FitsException

write

public void write(BufferedDataOutputStream os)
           throws FitsException

Description copied from class: Data

Write the data -- including any buffering needed

Overrides:

write in class Data

Parameters:

os - The output stream on which to write the data.

Throws:

FitsException

getHeapSize

public int getHeapSize()

getDimens

public int[][] getDimens()

getBases

public Class[] getBases()

getTypes

public char[] getTypes()

getSizes

public int[] getSizes()