uk.ac.starlink.pds4

Class BasePds4StarTable

java.lang.Object

uk.ac.starlink.table.AbstractStarTable

uk.ac.starlink.pds4.Pds4StarTable

uk.ac.starlink.pds4.BasePds4StarTable

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, StarTable

public class BasePds4StarTable
extends Pds4StarTable

Concrete Pds4StarTable subclass for fixed-length-record (binary and character) PDS tables.

Since:

24 Nov 2021

Field Summary

Fields inherited from class uk.ac.starlink.pds4.Pds4StarTable

DESCRIPTION_INFO

Constructor Summary

Constructors

Constructor and Description
BasePds4StarTable(BaseTable table, java.net.URL contextUrl) Constructor.

Method Summary

Modifier and Type	Method and Description
java.lang.Object	getCell(long lrow, int icol) The AbstractStarTable implementation of this method throws an UnsupportedOperationException, since unless otherwise provided there is no random access.
int	getColumnCount() Returns the number of columns in this table.
ColumnInfo	getColumnInfo(int icol) Returns the object describing the data in a given column.
java.lang.Object[]	getRow(long lrow) The AbstractStarTable implementation of this method constructs a row by repeated invocation of AbstractStarTable.getCell(long, int).
RowAccess	getRowAccess() Returns an object which can provide random access to this table's data, if random access is implemented.
RowSequence	getRowSequence() Returns an object which can iterate over all the rows in the table sequentially.
boolean	isRandom() The AbstractStarTable implementation of this method returns false.

Methods inherited from class uk.ac.starlink.pds4.Pds4StarTable

getRowCount

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

checkedLongToInt, close, getColumnAuxDataInfos, 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

BasePds4StarTable

public BasePds4StarTable(BaseTable table,
                         java.net.URL contextUrl)
                  throws java.io.IOException

Constructor.

Parameters:

table - table object on which this table is based

contextUrl - parent URL for the PDS4 label

Throws:

java.io.IOException

Method Detail

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

getRowSequence

public RowSequence getRowSequence()
                           throws java.io.IOException

Description copied from interface: StarTable

Returns an object which can iterate over all the rows in the table sequentially. Each such returned object is safe for use within a single thread, but not in general from multiple threads concurrently.

Specified by:

getRowSequence in interface StarTable

Specified by:

getRowSequence in class AbstractStarTable

Returns:

new RowSequence

Throws:

java.io.IOException - if there is an error providing access

isRandom

public boolean isRandom()

Description copied from class: AbstractStarTable

The AbstractStarTable implementation of this method returns false.

Specified by:

isRandom in interface StarTable

Overrides:

isRandom in class AbstractStarTable

Returns:

true if table random access methods are available

getRow

public java.lang.Object[] getRow(long lrow)
                          throws java.io.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:

java.io.IOException - if there is an error reading the data

getCell

public java.lang.Object getCell(long lrow,
                                int icol)
                         throws java.io.IOException

Description copied from class: AbstractStarTable

The AbstractStarTable implementation of this method throws an UnsupportedOperationException, since unless otherwise provided there is no random access.

Specified by:

getCell in interface StarTable

Overrides:

getCell in class AbstractStarTable

Parameters:

lrow - the index of the cell's row

icol - the index of the cell's column

Returns:

the contents of this cell

Throws:

java.io.IOException - if there is an error reading the data

getRowAccess

public RowAccess getRowAccess()
                       throws java.io.IOException

Description copied from interface: StarTable

Returns an object which can provide random access to this table's data, if random access is implemented. Each such returned object is safe for use within a single thread, but not in general from multiple threads concurrently.

Specified by:

getRowAccess in interface StarTable

Overrides:

getRowAccess in class AbstractStarTable

Returns:

new RowAccess

Throws:

java.io.IOException - if there is an error setting up access