org.knime.base.node.preproc.groupby
Class GroupByTable

java.lang.Object
  org.knime.base.node.preproc.groupby.GroupByTable

Direct Known Subclasses:

BigGroupByTable, MemoryGroupByTable

public abstract class GroupByTable
extends Object

Author:

Tobias Koetter, University of Konstanz

Constructor Summary

protected

GroupByTable(ExecutionContext exec, BufferedDataTable inDataTable, List<String> groupByCols, ColumnAggregator[] colAggregators, GlobalSettings globalSettings, boolean sortInMemory, boolean enableHilite, ColumnNamePolicy colNamePolicy, boolean retainOrder) Constructor for class GroupByTable.

Method Summary

protected void	addHiliteMapping(RowKey newKey, Set<RowKey> oldKeys)
protected void	addSkippedGroup(String colName, String skipMsg, DataCell[] groupVals)
static BufferedDataTable	appendOrderColumn(ExecutionContext exec, BufferedDataTable dataTable, Set<String> workingCols, String retainOrderCol)
static void	checkGroupCols(DataTableSpec spec, List<String> groupCols)
protected abstract BufferedDataTable	createGroupByTable(ExecutionContext exec, BufferedDataTable dataTable, DataTableSpec resultSpec, int[] groupColIdx)
static DataTableSpec	createGroupByTableSpec(DataTableSpec spec, List<String> groupColNames, ColumnAggregator[] columnAggregators, ColumnNamePolicy colNamePolicy)
static String	createSkippedGroupName(DataCell[] groupVals)
BufferedDataTable	getBufferedTable()
ColumnAggregator[]	getColAggregators()
GlobalSettings	getGlobalSettings()
List<String>	getGroupCols()
Map<RowKey,Set<RowKey>>	getHiliteMapping() the hilite translation Map or null if the enableHilte flag in the constructor was set to false.
Map<String,Collection<Pair<String,String>>>	getSkippedGroupsByColName() Returns a Map with all skipped groups.
String	getSkippedGroupsMessage(int maxGroups, int maxCols)
boolean	isEnableHilite()
boolean	isRetainOrder()
boolean	isSortInMemory()
static BufferedDataTable	sortTable(ExecutionContext exec, BufferedDataTable table2sort, List<String> sortCols, boolean sortInMemory)

Methods inherited from class java.lang.Object

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

Constructor Detail

GroupByTable

protected GroupByTable(ExecutionContext exec,
                       BufferedDataTable inDataTable,
                       List<String> groupByCols,
                       ColumnAggregator[] colAggregators,
                       GlobalSettings globalSettings,
                       boolean sortInMemory,
                       boolean enableHilite,
                       ColumnNamePolicy colNamePolicy,
                       boolean retainOrder)
                throws CanceledExecutionException

Constructor for class GroupByTable.

Parameters:

exec - the ExecutionContext

inDataTable - the table to aggregate

groupByCols - the name of all columns to group by

colAggregators - the aggregation columns with the aggregation method to use in the order the columns should be appear in the result table numerical columns

globalSettings - the global settings

sortInMemory - true if the table should be sorted in the memory

enableHilite - true if a row key map should be maintained to enable hiliting

colNamePolicy - the ColumnNamePolicy for the aggregation columns input table if set to true

retainOrder - true if the original row order should be retained

Throws:

CanceledExecutionException - if the user has canceled the execution

Method Detail

createGroupByTable

protected abstract BufferedDataTable createGroupByTable(ExecutionContext exec,
                                                        BufferedDataTable dataTable,
                                                        DataTableSpec resultSpec,
                                                        int[] groupColIdx)
                                                 throws CanceledExecutionException

Parameters:

exec - the ExecutionContext

dataTable - the data table to aggregate

resultSpec - the result DataTableSpec

groupColIdx - the group column indices

Returns:

the aggregated input table

Throws:

CanceledExecutionException - if the operation has been canceled

getGroupCols

public List<String> getGroupCols()

Returns:

the columns to group by

getGlobalSettings

public GlobalSettings getGlobalSettings()

Returns:

the global settings

isEnableHilite

public boolean isEnableHilite()

Returns:

if a hilite mapping should be maintained

isSortInMemory

public boolean isSortInMemory()

Returns:

if sorting should be performed in memory

isRetainOrder

public boolean isRetainOrder()

Returns:

if the input table order should be retained

getColAggregators

public ColumnAggregator[] getColAggregators()

Returns:

the colAggregators

appendOrderColumn

public static BufferedDataTable appendOrderColumn(ExecutionContext exec,
                                                  BufferedDataTable dataTable,
                                                  Set<String> workingCols,
                                                  String retainOrderCol)
                                           throws CanceledExecutionException

Parameters:

exec - the ExecutionContext

dataTable - the BufferedDataTable to add the order column to

workingCols - the names of all columns needed for grouping

retainOrderCol - the name of the order column

Returns:

the given table with the appended order column

Throws:

CanceledExecutionException - if the operation has been canceled

sortTable

public static BufferedDataTable sortTable(ExecutionContext exec,
                                          BufferedDataTable table2sort,
                                          List<String> sortCols,
                                          boolean sortInMemory)
                                   throws CanceledExecutionException

Parameters:

exec - ExecutionContext

table2sort - the BufferedDataTable to sort

sortCols - the columns to sort by

sortInMemory - the sort in memory flag

Returns:

the sorted BufferedDataTable

Throws:

CanceledExecutionException - if the operation has been canceled

createSkippedGroupName

public static String createSkippedGroupName(DataCell[] groupVals)

Parameters:

groupVals - the group values of the skipped group

Returns:

the group name

addHiliteMapping

protected void addHiliteMapping(RowKey newKey,
                                Set<RowKey> oldKeys)

Parameters:

newKey - the new RowKey

oldKeys - all old RowKeys

addSkippedGroup

protected void addSkippedGroup(String colName,
                               String skipMsg,
                               DataCell[] groupVals)

Parameters:

colName - the name of the column

skipMsg - the skip message to display

groupVals - the skipped group values

createGroupByTableSpec

public static final DataTableSpec createGroupByTableSpec(DataTableSpec spec,
                                                         List<String> groupColNames,
                                                         ColumnAggregator[] columnAggregators,
                                                         ColumnNamePolicy colNamePolicy)

Parameters:

spec - the original DataTableSpec

groupColNames - the name of all columns to group by

columnAggregators - the aggregation columns with the aggregation method to use in the order the columns should be appear in the result table

colNamePolicy - the ColumnNamePolicy for the aggregation columns

Returns:

the result DataTableSpec

getHiliteMapping

public Map<RowKey,Set<RowKey>> getHiliteMapping()

the hilite translation Map or null if the enableHilte flag in the constructor was set to false. The key of the Map is the row key of the new group row and the corresponding value is the Collection with all old row keys which belong to this group.

Returns:

the hilite translation Map or null if the enableHilte flag in the constructor was set to false.

getSkippedGroupsByColName

public Map<String,Collection<Pair<String,String>>> getSkippedGroupsByColName()

Returns a Map with all skipped groups. The key of the Map is the name of the column and the value is a Collection with Pair objects with the group name as first and the corresponding skip message as second object.

Returns:

a Map with all skipped groups

getSkippedGroupsMessage

public String getSkippedGroupsMessage(int maxGroups,
                                      int maxCols)

Parameters:

maxGroups - the maximum number of skipped groups to display

maxCols - the maximum number of columns to display per group

Returns:

String message with the skipped groups per column or null if no groups where skipped

checkGroupCols

public static void checkGroupCols(DataTableSpec spec,
                                  List<String> groupCols)
                           throws IllegalArgumentException

Parameters:

spec - the DataTableSpec to check

groupCols - the group by column name List

Throws:

IllegalArgumentException - if one of the group by columns doesn't exists in the given DataTableSpec

getBufferedTable

public BufferedDataTable getBufferedTable()

Returns:

the aggregated BufferedDataTable