infovis.metadata
Class AtLeafAggregation

java.lang.Object
  extended by infovis.metadata.AtLeafAggregation
All Implemented Interfaces:
Aggregation, AggregationConstants, Constants

public class AtLeafAggregation
extends Object
implements Aggregation

A Column in a Tree is considerer aggregated at the leaf level it only its leave nodes have defined values. Such columns can the be used using most aggregation types (additive, min, max, etc.) by filling the inner nodes with the desired aggregation function without breaking the column's visible semantic.

Version:
$Revision: 1.7 $
Author:
Jean-Daniel Fekete
InfoVis factory arguments:
AggregationFactory AtLeaf

Field Summary
 
Fields inherited from interface infovis.metadata.AggregationConstants
AGGREGATE_COMPATIBLE, AGGREGATE_NO, AGGREGATE_YES, AGGREGATION_TYPE, AGGREGATION_TYPE_ADDITIVE, AGGREGATION_TYPE_ATLEAF, AGGREGATION_TYPE_CONCAT, AGGREGATION_TYPE_MAX, AGGREGATION_TYPE_MEAN, AGGREGATION_TYPE_MIN, AGGREGATION_TYPE_NONE
 
Fields inherited from interface infovis.metadata.Constants
CONTRIBUTOR, COVERAGE, CREATOR, DATE, DESCRITION, FORMAT, IDENTIFIER, LANGUAGE, PUBLISHER, RELATION, RIGHTS, SOURCE, SUBJECT, TITLE, TYPE
 
Constructor Summary
AtLeafAggregation()
           
 
Method Summary
 Column aggregate(Column src, Tree tree, Column dst)
          Computes the aggregation values of the specified source column into the destination column.
static AtLeafAggregation getInstance()
           
 String getType()
          Returns the type name of the aggregation.
 boolean isAggregating(Column col, Tree tree)
          Checks whether a column is aggregating following the class aggregation scheme.
static boolean isAtLeaf(Column col, Tree tree)
           
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

AtLeafAggregation

public AtLeafAggregation()
Method Detail

getInstance

public static AtLeafAggregation getInstance()

isAggregating

public boolean isAggregating(Column col,
                             Tree tree)
Description copied from interface: Aggregation
Checks whether a column is aggregating following the class aggregation scheme.

Specified by:
isAggregating in interface Aggregation
Parameters:
col - the column
tree - the tree
Returns:
true if the column follows the aggregation scheme, false otherwise.

aggregate

public Column aggregate(Column src,
                        Tree tree,
                        Column dst)
Description copied from interface: Aggregation
Computes the aggregation values of the specified source column into the destination column. Source and destination should be allocated and of the right type.

Specified by:
aggregate in interface Aggregation
Parameters:
src - the source column
tree - the tree
dst - the destination column
Returns:
the dst column.

getType

public String getType()
Description copied from interface: Aggregation
Returns the type name of the aggregation.

Specified by:
getType in interface Aggregation
Returns:
the type name of the aggregation.

isAtLeaf

public static final boolean isAtLeaf(Column col,
                                     Tree tree)


Copyright 2005 by Jean-Daniel Fekete and INRIA, France All rights reserved.