Package org.pentaho.reporting.engine.classic.core.function

Class TotalGroupSumFunction

java.lang.Object

org.pentaho.reporting.engine.classic.core.function.AbstractExpression

org.pentaho.reporting.engine.classic.core.function.AbstractFunction

org.pentaho.reporting.engine.classic.core.function.TotalGroupSumFunction

All Implemented Interfaces:

Serializable, Cloneable, EventListener, ReportListener, AggregationFunction, Expression, FieldAggregationFunction, Function

Direct Known Subclasses:

TotalPageSumFunction

public class TotalGroupSumFunction
extends AbstractFunction
implements FieldAggregationFunction

A report function that calculates the sum of one field (column) from the Data-Row. This function produces a global total. The total sum of the group is known when the group processing starts and the report is not performing a prepare-run. The sum is calculated in the prepare run and recalled in the printing run.

The function can be used in two ways:

• to calculate a sum for the entire report;
• to calculate a sum within a particular group;

This function expects its input values to be either java.lang.Number instances or Strings that can be parsed to java.lang.Number instances using a java.text.DecimalFormat.

The function understands two parameters, the field parameter is required and denotes the name of an ItemBand-field which gets summed up.

The parameter group denotes the name of a group. When this group is started, the counter gets reset to null. This parameter is optional.

Author:

Thomas Morgner

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected ReportStateKey	currentGroupKey	The current group key is used to store the result for the current group.
protected static BigDecimal	ZERO	A useful constant representing zero.

Constructor Summary

Constructors

Constructor	Description
TotalGroupSumFunction()	Constructs a new function.

Method Summary

Modifier and Type	Method	Description
protected void	clear()
Object	clone()	Clones the expression.
String	getCrosstabFilterGroup()
String	getField()	Returns the field used by the function.
String	getGroup()	Returns the name of the group to be totalled.
Expression	getInstance()	Return a completly separated copy of this function.
Object	getValue()	Return the current function value.
void	groupStarted(ReportEvent event)	Receives notification that a group has started.
protected boolean	isPrepareRunLevel(ReportEvent event)
void	itemsAdvanced(ReportEvent event)	Receives notification that a row of data is being processed.
void	reportInitialized(ReportEvent event)	Receives notification that the report has started.
void	setCrosstabFilterGroup(String crosstabFilterGroup)
void	setField(String field)	Sets the field name for the function.
void	setGroup(String group)	Defines the name of the group to be totalled.
void	summaryRowSelection(ReportEvent event)	A crosstab specific event notifying crosstab-aware functions to select the result for the summary row cell that will be printed next.

Methods inherited from class org.pentaho.reporting.engine.classic.core.function.AbstractFunction

groupFinished, itemsFinished, itemsStarted, reportDone, reportFinished, reportStarted

Methods inherited from class org.pentaho.reporting.engine.classic.core.function.AbstractExpression

getDataRow, getDependencyLevel, getName, getReportConfiguration, getResourceBundleFactory, getRuntime, isActive, isDeepTraversing, isPreserve, setActive, setDependencyLevel, setName, setPreserve, setRuntime

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.pentaho.reporting.engine.classic.core.function.Expression

getDataRow, getDependencyLevel, getName, getReportConfiguration, getResourceBundleFactory, getRuntime, isActive, isDeepTraversing, isPreserve, setDependencyLevel, setName, setRuntime

Methods inherited from interface org.pentaho.reporting.engine.classic.core.event.ReportListener

groupFinished, itemsFinished, itemsStarted, reportDone, reportFinished, reportStarted

Field Detail

ZERO

protected static final BigDecimal ZERO

A useful constant representing zero.

currentGroupKey

protected transient ReportStateKey currentGroupKey

The current group key is used to store the result for the current group.

Constructor Detail

TotalGroupSumFunction

public TotalGroupSumFunction()

Constructs a new function.

Initially the function has no name...be sure to assign one before using the function.

Method Detail

reportInitialized

public void reportInitialized(ReportEvent event)

Receives notification that the report has started.

Specified by:

reportInitialized in interface ReportListener

Overrides:

reportInitialized in class AbstractFunction

Parameters:

event - the event.

isPrepareRunLevel

protected boolean isPrepareRunLevel(ReportEvent event)

groupStarted

public void groupStarted(ReportEvent event)

Receives notification that a group has started.

Specified by:

groupStarted in interface ReportListener

Overrides:

groupStarted in class AbstractFunction

Parameters:

event - the event.

clear

protected void clear()

itemsAdvanced

public void itemsAdvanced(ReportEvent event)

Receives notification that a row of data is being processed.

Specified by:

itemsAdvanced in interface ReportListener

Overrides:

itemsAdvanced in class AbstractFunction

Parameters:

event - the event.

clone

public Object clone()
             throws CloneNotSupportedException

Description copied from class: AbstractExpression

Clones the expression. The expression should be reinitialized after the cloning.

Expressions maintain no state, cloning is done at the beginning of the report processing to disconnect the expression from any other object space.

Specified by:

clone in interface Expression

Overrides:

clone in class AbstractExpression

Returns:

a clone of this expression.

Throws:

CloneNotSupportedException - this should never happen.

summaryRowSelection

public void summaryRowSelection(ReportEvent event)

Description copied from class: AbstractFunction

A crosstab specific event notifying crosstab-aware functions to select the result for the summary row cell that will be printed next.

Specified by:

summaryRowSelection in interface ReportListener

Overrides:

summaryRowSelection in class AbstractFunction

Parameters:

event - The report event.

getGroup

public String getGroup()

Returns the name of the group to be totalled.

Specified by:

getGroup in interface AggregationFunction

Returns:

the group name.

setGroup

public void setGroup(String group)

Defines the name of the group to be totalled. If the name is null, all groups are totalled.

Specified by:

setGroup in interface AggregationFunction

Parameters:

group - the group name.

getValue

public Object getValue()

Return the current function value.

The value depends (obviously) on the function implementation. For example, a page counting function will return the current page number.

Specified by:

getValue in interface Expression

Returns:

The value of the function.

getField

public String getField()

Returns the field used by the function. The field name corresponds to a column name in the report's data-row.

Specified by:

getField in interface FieldAggregationFunction

Returns:

The field name.

setField

public void setField(String field)

Sets the field name for the function. The field name corresponds to a column name in the report's data-row.

Specified by:

setField in interface FieldAggregationFunction

Parameters:

field - the field name.

getInstance

public Expression getInstance()

Return a completly separated copy of this function. The copy does no longer share any changeable objects with the original function.

Specified by:

getInstance in interface Expression

Overrides:

getInstance in class AbstractExpression

Returns:

a copy of this function.

getCrosstabFilterGroup

public String getCrosstabFilterGroup()

Specified by:

getCrosstabFilterGroup in interface AggregationFunction

setCrosstabFilterGroup

public void setCrosstabFilterGroup(String crosstabFilterGroup)

Specified by:

setCrosstabFilterGroup in interface AggregationFunction