uk.ac.starlink.table

Class RowListStarTable

java.lang.Object

uk.ac.starlink.table.AbstractStarTable

uk.ac.starlink.table.RandomStarTable

uk.ac.starlink.table.RowListStarTable

All Implemented Interfaces:

Closeable, AutoCloseable, StarTable

public class RowListStarTable
extends RandomStarTable

Simple modifiable StarTable implementation. It has a fixed number of columns and a variable number of rows; rows can be added, removed and modified.

The current implementation stores the data in a List of Object[] arrays - each list element contains the cells of one row of the table. Thus currently you can't store more than Integer.MAX_VALUE rows.

Some validation is performed when objects are inserted into the table, but it is possible to subvert this - the table itself can't guarantee that its data structures represent a legal table.

Author:

Mark Taylor (Starlink)

Constructor Summary

Constructors

Constructor and Description
RowListStarTable(ColumnInfo[] colInfos) Constructs a new RowListStarTable specifying the columns that it will contain.
RowListStarTable(StarTable template) Constructs a new RowListStarTable with its column and table metadata copied from an existing table.

Method Summary

Modifier and Type	Method and Description
void	addRow(Object[] values) Adds a new row to the end of the table.
void	clearRows() Removes all rows from the table.
Object	getCell(long lrow, int icol) Implementations of this method must be safe for concurrent calls from multiple threads.
int	getColumnCount() Returns the number of columns in this table.
ColumnInfo	getColumnInfo(int icol) Returns the object describing the data in a given column.
Object[]	getRow(long lrow) The AbstractStarTable implementation of this method constructs a row by repeated invocation of AbstractStarTable.getCell(long, int).
long	getRowCount() Implementations must supply a non-negative return value.
void	insertRow(long lrow, Object[] values) Adds a new row in the middle of the table.
void	removeRow(long lrow) Removes an existing row from the table.
void	setCell(long lrow, int icol, Object value) Sets the value of a given cell in the table.
void	setRow(long lrow, Object[] values) Sets the value of a given row in the table.

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

getRowAccess, getRowSequence, isRandom

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

RowListStarTable

public RowListStarTable(ColumnInfo[] colInfos)

Constructs a new RowListStarTable specifying the columns that it will contain.

Parameters:

colInfos - array of objects defining the columns of the table

RowListStarTable

public RowListStarTable(StarTable template)

Constructs a new RowListStarTable with its column and table metadata copied from an existing table. The data of the template is ignored.

Parameters:

template - template table supplying column and table metadata

Method Detail

getRowCount

public long getRowCount()

Description copied from class: RandomStarTable

Implementations must supply a non-negative return value.

Specified by:

getRowCount in interface StarTable

Specified by:

getRowCount in class RandomStarTable

Returns:

the number of rows in the table

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

getCell

public Object getCell(long lrow,
                      int icol)

Description copied from class: RandomStarTable

Implementations of this method must be safe for concurrent calls from multiple threads.

Specified by:

getCell in interface StarTable

Specified by:

getCell in class RandomStarTable

Parameters:

lrow - the index of the cell's row

icol - the index of the cell's column

Returns:

the contents of this cell

getRow

public Object[] getRow(long lrow)

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

setCell

public void setCell(long lrow,
                    int icol,
                    Object value)

Sets the value of a given cell in the table. value has to have a class compatible with its column.

Parameters:

lrow - row index

icol - column index

value - new value for the cell at lrow, icol

Throws:

IllegalArgumentException - if value is not compatible with column icol

setRow

public void setRow(long lrow,
                   Object[] values)

Sets the value of a given row in the table. Overwrites the existing values of the cells in that row. values has to have the same number of elements as there are columns in this table, and its elements have to have classes compatible with the table columns.

Parameters:

lrow - row index

values - new values for the cells in row lrow

Throws:

IllegalArgumentException - if values has the wrong number of elements or they are of the wrong class

addRow

public void addRow(Object[] values)

Adds a new row to the end of the table. values has to have the same number of elements as there are columns in this table, and its elements have to have classes compatible with the table columns.

Parameters:

values - values for the cells in the new row

Throws:

IllegalArgumentException - if values has the wrong number of elements or they are of the wrong class

insertRow

public void insertRow(long lrow,
                      Object[] values)

Adds a new row in the middle of the table. Rows after lrow will be shoved down by one. values has to have the same number of elements as there are columns in this table, and its elements have to have classes compatible with the table columns.

Parameters:

lrow - row index for the new row

values - values for the cells in the new row

Throws:

IllegalArgumentException - if values has the wrong number of elements or they are of the wrong class

removeRow

public void removeRow(long lrow)

Removes an existing row from the table. Rows after lrow will be moved up by one.

Parameters:

lrow - index of the row to remove

clearRows

public void clearRows()

Removes all rows from the table.