borland Packages Class Hierarchy jbcl.dataset Package Index
java.lang.Object +----borland.jbcl.dataset.AggDescriptor
Constructors Properties Methods
Implements Serializable
The AggDescriptor class collects the properties associated with an aggregation calculation. It is associated with a Column by the Column component's agg property. In the JBuilder Inspector, this object is accessed from the agg property. Selecting this property displays the Agg property editor where you can define the properties for your aggregate operation. This editor allows you to define:
Set the agg property of a Column component to an instance of this class to define the type of aggregation to perform: count, sum, minimum value or maximum value. You specify a single column for the aggregation operation. You can optionally include a set of Column names to base the grouping logic of the aggregation (subtotals) or, if left unspecified, the calculation is done across an entire DataSet.
For more information on using aggregators in calculated columns, see Aggregating data with calculated fields in the Database Application Developer's Guide. For more information on the Agg property editor, see the F1 Help topic Agg Property Editor.
For examples of applications that use aggregators, see the following projects in the specified directories of your JBuilder installation:
public AggDescriptor(java.lang.String[] groupColumnNames, java.lang.String aggColumnName, borland.jbcl.dataset.AggOperator aggOperator)Constructs an AggDescriptor according to the following parameters:
public String getAggColumnName()Read-only property that returns the Column (by name) to perform the aggregation on.
public AggOperator getAggOperator()Read-only property that specifies the aggregation operation to perform. Valid values are:
public String[] getGroupColumnNames()Read-only property that returns the array of Column names that define the groups of rows to aggregate on.