uk.ac.starlink.table.join

Class Match1Type

java.lang.Object

uk.ac.starlink.table.join.Match1Type

public abstract class Match1Type
extends Object

Defines how an output table is created from the results of an internal (single-table) match operation. This class contains several factory methods for generating sensible output tables from an internal match. Others are possible.

Basic use of this class looks something like:

     LinkSet linkSet = type.processLinks(RowMatcher.findInternalMatches());
     StarTable table = createMatchTable(inTable, linkSet.toSorted());
 

(the sorting is optional).

Since:

15 Nov 2007

Author:

Mark Taylor

Constructor Summary

Constructors

Constructor and Description
Match1Type()

Method Summary

Modifier and Type	Method and Description
static Match1Type	createEliminateMatchesType(int retainCount) Factory method returning a type object which eliminates rows forming part of the same match group.
static Match1Type	createIdentifyType() Factory method returning a type object which identifies matched rows by adding some additional columns to the input.
abstract StarTable	createMatchTable(StarTable inTable, Collection<RowLink> rowLinks) Generates an output table given an input table and the RowLink sequence which defines how its rows are related to each other by matching.
static Match1Type	createWideType(int grpSize) Factory method returning a type object which aligns match groups with each other in the rows of a new wide table.
abstract LinkSet	processLinks(LinkSet rowLinks) Performs additional processing specific to this match type on the raw LinkSet produced by {RowMatcher#findInternalMatches}.

Methods inherited from class java.lang.Object

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

Constructor Detail

Match1Type

public Match1Type()

Method Detail

processLinks

public abstract LinkSet processLinks(LinkSet rowLinks)

Performs additional processing specific to this match type on the raw LinkSet produced by {RowMatcher#findInternalMatches}. The input linkset may be modified, and the output value may or may not be the same instance as the input.

Parameters:

rowLinks - link set representing a single-table (internal) match

Returns:

link set ready for table creation

createMatchTable

public abstract StarTable createMatchTable(StarTable inTable,
                                           Collection<RowLink> rowLinks)

Generates an output table given an input table and the RowLink sequence which defines how its rows are related to each other by matching.

Parameters:

inTable - input table

rowLinks - links resulting from a call to processLinks(uk.ac.starlink.table.join.LinkSet)

createIdentifyType

public static Match1Type createIdentifyType()

Factory method returning a type object which identifies matched rows by adding some additional columns to the input. These flag which rows match which other ones and give a group size count.

Returns:

new identification type

createEliminateMatchesType

public static Match1Type createEliminateMatchesType(int retainCount)

Factory method returning a type object which eliminates rows forming part of the same match group. All rows from a match group starting at index retainCount are removed from the output table. Thus retainCount=0 removes any rows which participate in matches with other ones, and retainCount=1 leaves just one from any such group.

Parameters:

retainCount - number of items to retain from each match group

createWideType

public static Match1Type createWideType(int grpSize)

Factory method returning a type object which aligns match groups with each other in the rows of a new wide table. The output table has columns like grpSize versions of the input table side by side, and where there are exactly grpSize matches in a group they form a row. Rows which are not part of a grpSize-element match do not appear in the output.

Parameters:

grpSize - size of group we are interested in