org.pentaho.reporting.engine.classic.core
Class Group

java.lang.Object
  org.pentaho.reporting.engine.classic.core.Element
      org.pentaho.reporting.engine.classic.core.Section
          org.pentaho.reporting.engine.classic.core.Group

All Implemented Interfaces:

Serializable, Cloneable, DataTarget, ReportElement

Direct Known Subclasses:

CrosstabColumnGroup, CrosstabGroup, CrosstabOtherGroup, CrosstabRowGroup, RelationalGroup

public abstract class Group
extends Section

A report group. Reports can contain any number of (nested) groups. The order of the fields is not important. If the group does not contain any fields, the group spans the whole report from the first to the last row (such a group is called the default group).

The group's field list should not be modified after the group was added to the group list, or the results are undefined.

Groups of the same GroupList must have a subgroup relation. The designated child group must contain all fields of the direct parent plus at least one new field. There is no requirement, that the referenced field actually exists, if it doesn't, null is assumed as field value.

It is recommended that the name of the group is unique within the report. The name will not be used internally to identify the group, but most functions depend on a recognizable group name to identify the group to be processed.

Author:

David Gilbert, Thomas Morgner

See Also:

GroupList, Serialized Form

Field Summary

static String

ANONYMOUS_GROUP_PREFIX The internal constant to mark anonymous group names.

Fields inherited from class org.pentaho.reporting.engine.classic.core.Element

ANONYMOUS_ELEMENT_PREFIX

Method Summary

Object	clone() Clones this Element.
Element	derive(boolean preserveElementInstanceIds) Creates a deep copy of this element and regenerates all instance-ids.
GroupBody	getBody()
ReportElement	getElement(int index) Returns the element stored add the given index.
int	getElementCount() Returns the number of elements in this section.
GroupFooter	getFooter() Returns the group footer.
GroupHeader	getHeader() Returns the group header.
abstract boolean	isGroupChange(DataRow dataRow)
void	setBody(GroupBody body)
void	setElementAt(int index, Element element)
void	setFooter(GroupFooter footer) Sets the footer for the group.
void	setHeader(GroupHeader header) Sets the header for the group.

Methods inherited from class org.pentaho.reporting.engine.classic.core.Element

derive, getAttribute, getAttributeExpression, getAttributeExpressionNames, getAttributeExpressionNamespaces, getAttributeNames, getAttributeNamespaces, getAttributes, getChangeTracker, getContentBase, getDataSource, getDefinitionSource, getElementType, getElementTypeName, getHRefTarget, getId, getMetaData, getName, getObjectID, getParent, getParentSection, getReportDefinition, getStyle, getStyleExpression, getStyleExpressions, getTreeLock, getValue, isDynamicContent, isVisible, notifyNodeChildAdded, notifyNodeChildRemoved, notifyNodePropertiesChanged, notifyNodePropertiesChanged, notifyNodeStructureChanged, setAttribute, setAttribute, setAttributeExpression, setDataSource, setDynamicContent, setElementType, setHRefTarget, setId, setName, setStyleExpression, setVisible, toString

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

ANONYMOUS_GROUP_PREFIX

public static final String ANONYMOUS_GROUP_PREFIX

The internal constant to mark anonymous group names.

See Also:

Constant Field Values

Method Detail

getHeader

public GroupHeader getHeader()

Returns the group header.

The group header is a report band that contains elements that should be printed at the start of a group.

Returns:

the group header.

setHeader

public void setHeader(GroupHeader header)

Sets the header for the group.

Parameters:

header - the header (null not permitted).

Throws:

NullPointerException - if the given header is null

getBody

public GroupBody getBody()

setBody

public void setBody(GroupBody body)

getFooter

public GroupFooter getFooter()

Returns the group footer.

Returns:

the footer.

setFooter

public void setFooter(GroupFooter footer)

Sets the footer for the group.

Parameters:

footer - the footer (null not permitted).

Throws:

NullPointerException - if the given footer is null.

clone

public Object clone()
             throws CloneNotSupportedException

Clones this Element.

Specified by:

clone in interface DataTarget

Overrides:

clone in class Element

Returns:

a clone of this element.

Throws:

CloneNotSupportedException - should never be thrown.

derive

public Element derive(boolean preserveElementInstanceIds)
               throws CloneNotSupportedException

Description copied from class: Element

Creates a deep copy of this element and regenerates all instance-ids.

Overrides:

derive in class Element

Parameters:

preserveElementInstanceIds - defines whether this call generates new instance-ids for the derived elements. Instance-IDs are used by the report processor to recognize reoccurring elements and must not changed within the report run. Outside of the report processors new instance ids should be generated at all times to separate instances and to make them uniquely identifiable.

Returns:

the copy of the element.

Throws:

CloneNotSupportedException

isGroupChange

public abstract boolean isGroupChange(DataRow dataRow)

getElementCount

public int getElementCount()

Description copied from class: Section

Returns the number of elements in this section.

Specified by:

getElementCount in class Section

Returns:

the number of elements of this section.

getElement

public ReportElement getElement(int index)

Description copied from class: Section

Returns the element stored add the given index.

Specified by:

getElement in class Section

Parameters:

index - the element position within this section

Returns:

the element

setElementAt

public void setElementAt(int index,
                         Element element)

Specified by:

setElementAt in class Section