uk.ac.starlink.table.jdbc
Class SequentialResultSetStarTable

java.lang.Object
  uk.ac.starlink.table.AbstractStarTable
      uk.ac.starlink.table.jdbc.SequentialResultSetStarTable

All Implemented Interfaces:

StarTable

public class SequentialResultSetStarTable
extends AbstractStarTable

StarTable implementation based on a ResultSet. It can read through the data once, and no more.

Beware: it therefore breaks the general contract of StarTable, in that calls of getRowSequence() after the first one will throw a UnrepeatableSequenceException. Only use this class if you know that the table needs to be read once only.

Since:

23 Jul 2007

Constructor Summary

SequentialResultSetStarTable(java.sql.ResultSet rset)
Constructor.

SequentialResultSetStarTable(StarResultSet srset)
Constructs from a StarResultSet.

Method Summary

java.util.List<ValueInfo>	getColumnAuxDataInfos() Goes through the table columns (ColumnInfo objects) and picks out all the AuxData items which exist, generalising where necessary and returning a union of them in alphabetical order by name.
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.sql.ResultSet	getResultSet() Returns the result set on which this table is built.
long	getRowCount() Returns the number of rows in this table, if known.
RowSequence	getRowSequence() The first time it is called, returns an iterator over the rows of the result set.

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

checkedLongToInt, getCell, getName, getParameterByName, getParameters, getRow, getURL, isRandom, setName, setParameter, setParameters, setURL

Methods inherited from class java.lang.Object

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

Constructor Detail

SequentialResultSetStarTable

public SequentialResultSetStarTable(java.sql.ResultSet rset)
                             throws java.sql.SQLException

Constructor.

Parameters:

rset - result set containing data - should be positioned at start

Throws:

java.sql.SQLException

SequentialResultSetStarTable

public SequentialResultSetStarTable(StarResultSet srset)

Constructs from a StarResultSet.

Parameters:

srset - result set containing data - should be positioned at start

Method Detail

getResultSet

public java.sql.ResultSet getResultSet()

Returns the result set on which this table is built.

Returns:

result set

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

getRowCount

public long getRowCount()

Description copied from interface: StarTable

Returns the number of rows in this table, if known. If the number of rows cannot be (easily) determined, a value of -1 will be returned.

Specified by:

getRowCount in interface StarTable

Specified by:

getRowCount in class AbstractStarTable

Returns:

the number of rows, or -1

getColumnAuxDataInfos

public java.util.List<ValueInfo> getColumnAuxDataInfos()

Description copied from class: AbstractStarTable

Goes through the table columns (ColumnInfo objects) and picks out all the AuxData items which exist, generalising where necessary and returning a union of them in alphabetical order by name. Subclasses should override this if they can do better, for instance providing an order for the keys.

Specified by:

getColumnAuxDataInfos in interface StarTable

Overrides:

getColumnAuxDataInfos in class AbstractStarTable

Returns:

a list of all the auxiliary metadata ValueInfo items which in fact crop up in column metadata

See Also:

ColumnInfo.getAuxData()

getRowSequence

public RowSequence getRowSequence()
                           throws UnrepeatableSequenceException,
                                  java.io.IOException

The first time it is called, returns an iterator over the rows of the result set. Subsequent calls will throw an UnrepeatableSequenceException.

Specified by:

getRowSequence in interface StarTable

Specified by:

getRowSequence in class AbstractStarTable

Returns:

an object providing sequential access to the table data

Throws:

UnrepeatableSequenceException - if called more than once

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