uk.ac.starlink.table
Class JoinFixAction

java.lang.Object
  uk.ac.starlink.table.JoinFixAction

public abstract class JoinFixAction
extends Object

Class defining the possible actions for doctoring column names when joining tables. Joining tables can cause confusion if columns with the same names exist in some of them. An instance of this class defines how the join should behave in this case.

Since:

8 Sep 2005

Author:

Mark Taylor

See Also:

JoinStarTable

Field Summary

static JoinFixAction

NO_ACTION Action which causes names to be left alone.

Constructor Summary

protected

JoinFixAction(String name) Constructor.

Method Summary

static String	ensureUnique(String name, Collection others, boolean caseSensitive) Utility method which repeatedly doctors a name until it fails to match any of the others in a given collection.
abstract String	getFixedName(String origName, Collection otherNames) Returns a, possibly modified, name for a column in the context of existing column names.
static boolean	isDuplicate(String name, Collection others, boolean caseSensitive) Utility method to determine whether a given name is a duplicate of any in a given collection of other names.
static JoinFixAction	makeNumericDeduplicationAction(String delimiter, boolean caseSensitive) Returns an action which will deduplicate names by appending a numeric value to them.
static JoinFixAction	makeRenameAllAction(String appendage) Returns an action for renaming all column names with default options.
static JoinFixAction	makeRenameAllAction(String appendage, boolean caseSensitive, boolean ensureUnique) Returns an action for renaming all columns with additional options.
static JoinFixAction	makeRenameDuplicatesAction(String appendage) Returns an action for renaming duplicated column names with default options.
static JoinFixAction	makeRenameDuplicatesAction(String appendage, boolean caseSensitive, boolean ensureUnique) Returns an action for renaming duplicated column names with additional options.
String	toString() Returns this action's name.

Methods inherited from class java.lang.Object

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

Field Detail

NO_ACTION

public static final JoinFixAction NO_ACTION

Action which causes names to be left alone.

Constructor Detail

JoinFixAction

protected JoinFixAction(String name)

Constructor.

Parameters:

name - label for this action

Method Detail

getFixedName

public abstract String getFixedName(String origName,
                                    Collection otherNames)

Returns a, possibly modified, name for a column in the context of existing column names.

Parameters:

origName - input name

otherNames - list of names which may be duplicates of origName

Returns:

output name - may or may not be the same as origName

toString

public String toString()

Returns this action's name.

Overrides:

toString in class Object

isDuplicate

public static boolean isDuplicate(String name,
                                  Collection others,
                                  boolean caseSensitive)

Utility method to determine whether a given name is a duplicate of any in a given collection of other names.

Parameters:

name - name to test

others - potential duplicates of name

caseSensitive - true iff matching is to be done in a case-sensitive fashion

Returns:

true iff name matches any of the entries in others

ensureUnique

public static String ensureUnique(String name,
                                  Collection others,
                                  boolean caseSensitive)

Utility method which repeatedly doctors a name until it fails to match any of the others in a given collection. Currently some arbitrary scheme of appending characters is used.

Parameters:

name - input name

others - list of names that must not match

caseSensitive - whether matching others is case sensitive

Returns:

name similar to name but not matching others

makeRenameDuplicatesAction

public static JoinFixAction makeRenameDuplicatesAction(String appendage)

Returns an action for renaming duplicated column names with default options.

Parameters:

appendage - string to append to duplicate columns

Returns:

fixer

makeRenameDuplicatesAction

public static JoinFixAction makeRenameDuplicatesAction(String appendage,
                                                       boolean caseSensitive,
                                                       boolean ensureUnique)

Returns an action for renaming duplicated column names with additional options. The action indicates that column names which would be duplicated elsewhere in the result table should be modified by appending a given string.

Parameters:

appendage - string to append to duplicate columns

caseSensitive - whether duplicate location should be case sensitive

ensureUnique - if true, every effort will be made to ensure that the output name matches none of the others; if false, the output name may still match (but differently from the input one)

Returns:

fixer

makeRenameAllAction

public static JoinFixAction makeRenameAllAction(String appendage)

Returns an action for renaming all column names with default options.

Parameters:

appendage - string to append to columns

Returns:

fixer

makeRenameAllAction

public static JoinFixAction makeRenameAllAction(String appendage,
                                                boolean caseSensitive,
                                                boolean ensureUnique)

Returns an action for renaming all columns with additional options. The action indicates that all names will be modified by appending a given string.

Parameters:

appendage - string to append to columns

caseSensitive - whether duplicate location should be case sensitive (only relevant if ensureUnique is true)

ensureUnique - if true, every effort will be made to ensure that the output name matches none of the others;

Returns:

fixer

makeNumericDeduplicationAction

public static JoinFixAction makeNumericDeduplicationAction(String delimiter,
                                                           boolean caseSensitive)

Returns an action which will deduplicate names by appending a numeric value to them. The number is guaranteed unique; the value used is one higher than the currently highest used one

Parameters:

delimiter - string used to separate main part of name from numeric part

caseSensitive - whether duplicate location is case sensitive

Returns:

fixer