net.sf.saxon.style

Class XSLTemplate

java.lang.Object

net.sf.saxon.tree.linked.NodeImpl

net.sf.saxon.tree.linked.ElementImpl

net.sf.saxon.style.StyleElement

net.sf.saxon.style.XSLTemplate

All Implemented Interfaces:

java.lang.Iterable<NodeInfo>, javax.xml.transform.Source, javax.xml.transform.SourceLocator, Location, GroundedValue<NodeInfo>, Item<NodeInfo>, MutableNodeInfo, NamespaceResolver, NodeInfo, Sequence<NodeInfo>, StylesheetComponent, SteppingNode<NodeImpl>, SiblingCountingNode, org.xml.sax.Locator

public final class XSLTemplate
extends StyleElement
implements StylesheetComponent

An xsl:template element in the style sheet.

Field Summary

Fields inherited from class net.sf.saxon.style.StyleElement

ACTION_COMPILE, ACTION_FIXUP, ACTION_OPTIMIZE, ACTION_PROCESS_ATTRIBUTES, ACTION_TYPECHECK, ACTION_VALIDATE, actionsCompleted, defaultCollationName, defaultMode, defaultXPathNamespace, expandText, extensionNamespaces, IGNORED_INSTRUCTION, REPORT_ALWAYS, REPORT_DYNAMICALLY_UNLESS_FALLBACK_AVAILABLE, REPORT_IF_INSTANTIATED, REPORT_STATICALLY_UNLESS_FALLBACK_AVAILABLE, REPORT_UNLESS_FORWARDS_COMPATIBLE, reportingCircumstances, staticContext, validationError, version, YES_NO

Fields inherited from class net.sf.saxon.tree.linked.NodeImpl

NODE_LETTER

Fields inherited from interface net.sf.saxon.om.NodeInfo

IS_DTD_TYPE, IS_NILLED

Constructor Summary

Constructors

Constructor and Description
XSLTemplate()

Method Summary

Modifier and Type	Method and Description
protected void	addChild(NodeImpl node, int index) Add a child node to this node.
void	allocatePatternSlotNumbers() Allocate slot numbers to any local variables declared within a predicate within the match pattern
void	checkCompatibility(Component component) Check the compatibility of this component with another component that it is overriding
void	compact(int size) Compact the space used by this node
void	compileDeclaration(Compilation compilation, ComponentDeclaration decl) Compile: creates the executable form of the template
void	compileTemplateRule(Compilation compilation, Expression body, ComponentDeclaration decl)
void	generateByteCode(Optimizer opt) Generate byte code for the template (if appropriate)
NamedTemplate	getActor() Get the corresponding NamedTemplate object that results from the compilation of this StylesheetComponent
java.util.Set<Mode>	getApplicableModes() Get the modes to which this template rule applies
NamedTemplate	getCompiledNamedTemplate() Get the compiled template
int	getConstructType() Get the type of construct.
ItemType	getContextItemTypeForTemplateRule()
NodeImpl	getFirstChild() Get the first child node of the element
NodeImpl	getLastChild() Get the last child node of the element
Pattern	getMatch()
StructuredQName[]	getModeNames() Return the list of mode names to which this template rule is applicable.
protected NodeImpl	getNthChild(int n) Get the nth child node of the element (numbering from 0)
int	getNumberOfChildren() Determine how many children the node has
XSLLocalParam	getParam(StructuredQName name)
protected int	getRawSequenceNumber()
ItemType	getRequiredContextItemType()
protected long	getSequenceNumber() Get the node sequence number (in document order).
SlotManager	getSlotManager() Get associated Procedure (for details of stack frame)
java.lang.String	getStringValue() Return the string-value of the node, that is, the concatenation of the character content of all descendent elements and text nodes.
java.lang.CharSequence	getStringValueCS() Get the value of the item as a CharSequence.
SymbolicName	getSymbolicName() Get the symbolic name of the component, that is, the combination of the component kind and the qualified name
StructuredQName	getTemplateName() Return the name of this template.
java.util.Map<StructuredQName,TemplateRule>	getTemplateRulesByMode()
boolean	hasChildNodes() Determine if the node has any children.
void	index(ComponentDeclaration decl, PrincipalStylesheetModule top) Method supplied by declaration elements to add themselves to a stylesheet-level index
void	insertChildren(NodeInfo[] source, boolean atStart, boolean inherit) Insert a sequence of nodes as children of this node.
protected void	insertChildrenAt(NodeInfo[] source, int index, boolean inherit) Insert children before or after a given existing child
boolean	isDeclaration() Ask whether this node is a declaration, that is, a permitted child of xsl:stylesheet (including xsl:include and xsl:import).
boolean	isDeferredCompilation(Compilation compilation) Ask whether the compilation of the template should be deferred
boolean	isMayOmitContextItem()
boolean	isOmniMode() Ask whether this is a template rule with mode="#all
protected boolean	isPermittedChild(StyleElement child) Specify that xsl:param and xsl:context-item are permitted children
protected boolean	isWithinDeclaredStreamableConstruct()
protected AxisIterator	iterateChildren(NodeTest test) Get an enumeration of the children of this node
void	jitCompile(Compilation compilation, ComponentDeclaration decl) Code executed when the template is first executed under JIT.
boolean	markTailCalls() Mark tail-recursive calls on templates and functions.
protected boolean	mayContainParam() Determine whether this type of element is allowed to contain an xsl:param element
boolean	mayContainSequenceConstructor() Determine whether this type of element is allowed to contain a template-body
void	optimize(ComponentDeclaration declaration) This method is a bit of a misnomer, because it does more than invoke optimization of the template body.
void	prepareAttributes() Set the attribute list for the element.
void	processAllAttributes() Process the attributes of this element and all its children
void	register(ComponentDeclaration declaration) Registers the template rule with each Mode that it belongs to.
protected void	removeChild(NodeImpl child) Remove a given child
protected void	replaceChildrenAt(NodeInfo[] source, int index, boolean inherit) Replace child at a given index by new children
protected void	setChildren(java.lang.Object children) Set the children of this node
void	setCompilation(Compilation compilation)
void	setContextItemRequirements(ItemType type, boolean mayBeOmitted, boolean absentFocus) Set the required context item type.
protected void	setRawSequenceNumber(int seq)
void	validate(ComponentDeclaration decl) Check that the stylesheet element is valid.
void	validateSubtree(ComponentDeclaration decl, boolean excludeStylesheet) Recursive walk through the stylesheet to validate all nodes

Methods inherited from class net.sf.saxon.style.StyleElement

allocateLocalSlots, allocateLocation, bindLocalVariable, bindVariable, changesRetainedStaticContext, checkAttributeValue, checkEmpty, checkSortComesFirst, checkTopLevel, checkUnknownAttribute, compile, compileContentValueTemplate, compileError, compileError, compileError, compileError, compileError, compileErrorInAttribute, compileSequenceConstructor, compileSequenceConstructor, compileWarning, compileWarning, definesExcludedNamespace, definesExtensionElement, fallbackProcessing, findAncestorElement, findCollation, fixupReferences, forwardsCompatibleModeIsEnabled, generateId, getAttributeValue, getBaseURI, getBindingInformation, getCompilation, getConfiguration, getContainingPackage, getContainingSlotManager, getContainingStylesheet, getDeclaredVisibility, getDefaultCollationName, getDefaultMode, getDefaultValidation, getDefaultXPathNamespace, getEffectiveVersion, getEffectiveVersionAsString, getLastChildInstruction, getNamespaceResolver, getObjectName, getOverriddenComponent, getPackageData, getPrincipalStylesheetModule, getProperties, getProperty, getSchemaType, getStaticContext, getStaticContext, getTypeAnnotation, getUsedAttributeSets, getUsedPackage, getVisibility, getWithParamInstructions, getXslOriginal, hasImplicitBinding, interpretVisibilityValue, invalidAttribute, isActionCompleted, isConstructingComplexContent, isExcludedNamespace, isExpandingText, isExtensionNamespace, isInstruction, isSchemaAware, issueWarning, issueWarning, isTopLevel, makeAttributeValueTemplate, makeExpression, makeExpressionVisitor, makeExtendedSequenceType, makeNamespaceContext, makePattern, makeQName, makeRetainedStaticContext, makeSequenceType, makeSortKeys, makeTraceInstruction, mayContainFallback, postValidate, processAttributes, processBooleanAttribute, processDefaultCollationAttribute, processDefaultMode, processDefaultValidationAttribute, processDefaultXPathNamespaceAttribute, processExcludedNamespaces, processExpandTextAttribute, processExtensionElementAttribute, processStandardAttributes, processVersionAttribute, reportAbsence, seesAvuncularVariables, setActionCompleted, setIgnoreInstruction, setObjectName, setValidationError, substituteFor, typeCheck, typeCheck, undeclaredNamespaceError, validateChildren, validateValidationAttribute, xPath10ModeIsEnabled

Methods inherited from class net.sf.saxon.tree.linked.ElementImpl

addAttribute, addNamespace, copy, delete, fixupInsertedNamespaces, generateId, getAttributeList, getAttributeValue, getColumnNumber, getDeclaredNamespaces, getLineNumber, getNamespaceList, getNodeKind, getNodeName, getRoot, getSchemaType, getSystemId, getURIForPrefix, gsetAttributeCollection, initialise, isId, isIdref, isInScopeNamespace, isNilled, iteratePrefixes, removeAttribute, removeTypeAnnotation, rename, replaceStringValue, setAttributeList, setLocation, setNamespaceDeclarations, setNamespaceList, setNilled, setNodeName, setSystemId, setTypeAnnotation

Methods inherited from class net.sf.saxon.tree.linked.NodeImpl

atomize, compareOrder, effectiveBooleanValue, equals, getDisplayName, getFingerprint, getLocalPart, getNamePool, getNextInDocument, getNextSibling, getParent, getPhysicalRoot, getPrefix, getPreviousInDocument, getPreviousSibling, getRawParent, getSiblingPosition, getSuccessorElement, getTreeInfo, getURI, hasFingerprint, head, insertSiblings, isDeleted, iterate, iterateAxis, iterateAxis, newBuilder, replace, saveLocation, setRawParent, setSiblingPosition

Methods inherited from class java.lang.Object

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

Methods inherited from interface net.sf.saxon.om.NodeInfo

equals, getGenre, getPublicId, hashCode, isSameNodeInfo, isStreamed, toShortString

Methods inherited from interface net.sf.saxon.om.Item

getLength, itemAt, iterator, reduce, subsequence, toGroundedValue

Methods inherited from interface net.sf.saxon.om.GroundedValue

asIterable, materialize

Methods inherited from interface net.sf.saxon.om.Sequence

makeRepeatable

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

XSLTemplate

public XSLTemplate()

Method Detail

getActor

public NamedTemplate getActor()

Get the corresponding NamedTemplate object that results from the compilation of this StylesheetComponent

Specified by:

getActor in interface StylesheetComponent

Returns:

the compiled ComponentCode

setCompilation

public void setCompilation(Compilation compilation)

Overrides:

setCompilation in class StyleElement

isDeclaration

public boolean isDeclaration()

Ask whether this node is a declaration, that is, a permitted child of xsl:stylesheet (including xsl:include and xsl:import).

Overrides:

isDeclaration in class StyleElement

Returns:

true for this element

isDeferredCompilation

public boolean isDeferredCompilation(Compilation compilation)

Ask whether the compilation of the template should be deferred

Parameters:

compilation - the compilation

Returns:

true if compilation should be deferred

mayContainSequenceConstructor

public boolean mayContainSequenceConstructor()

Determine whether this type of element is allowed to contain a template-body

Overrides:

mayContainSequenceConstructor in class StyleElement

Returns:

true: yes, it may contain a template-body

mayContainParam

protected boolean mayContainParam()

Description copied from class: StyleElement

Determine whether this type of element is allowed to contain an xsl:param element

Overrides:

mayContainParam in class StyleElement

Returns:

true if this element is allowed to contain an xsl:param

isWithinDeclaredStreamableConstruct

protected boolean isWithinDeclaredStreamableConstruct()

Overrides:

isWithinDeclaredStreamableConstruct in class StyleElement

setContextItemRequirements

public void setContextItemRequirements(ItemType type,
                                       boolean mayBeOmitted,
                                       boolean absentFocus)

Set the required context item type. Used when there is an xsl:context-item child element

Parameters:

type - the required context item type

mayBeOmitted - true if the context item may be absent

absentFocus - true if use=absent is specified

isPermittedChild

protected boolean isPermittedChild(StyleElement child)

Specify that xsl:param and xsl:context-item are permitted children

Overrides:

isPermittedChild in class StyleElement

Parameters:

child - the child that may or may not be permitted

Returns:

true if the child is permitted.

getTemplateName

public StructuredQName getTemplateName()

Return the name of this template. Note that this may be called before prepareAttributes has been called.

Returns:

the name of the template as a Structured QName.

getSymbolicName

public SymbolicName getSymbolicName()

Description copied from interface: StylesheetComponent

Get the symbolic name of the component, that is, the combination of the component kind and the qualified name

Specified by:

getSymbolicName in interface StylesheetComponent

Returns:

the component's symbolic name

getRequiredContextItemType

public ItemType getRequiredContextItemType()

isMayOmitContextItem

public boolean isMayOmitContextItem()

checkCompatibility

public void checkCompatibility(Component component)

Description copied from interface: StylesheetComponent

Check the compatibility of this component with another component that it is overriding

Specified by:

checkCompatibility in interface StylesheetComponent

Parameters:

component - the overridden component

getParam

public XSLLocalParam getParam(StructuredQName name)

prepareAttributes

public void prepareAttributes()
                       throws XPathException

Description copied from class: StyleElement

Set the attribute list for the element. This is called to process the attributes (note the distinction from processAttributes in the superclass). Must be supplied in a subclass

Specified by:

prepareAttributes in class StyleElement

Throws:

XPathException - if a static error is detected

processAllAttributes

public void processAllAttributes()
                          throws XPathException

Description copied from class: StyleElement

Process the attributes of this element and all its children

Overrides:

processAllAttributes in class StyleElement

Throws:

XPathException - in the event of a static error being detected

getModeNames

public StructuredQName[] getModeNames()
                               throws XPathException

Return the list of mode names to which this template rule is applicable.

Returns:

the list of mode names. If the mode attribute is absent, #default is assumed. If #default is present explicitly or implicitly, it is replaced by the default mode, taken from the in-scope default-modes attribute, which defaults to #unnamed. The unnamed mode is represented by Mode.UNNAMED_MODE_NAME. The token #all translates to Mode.OMNI_MODE.

Throws:

XPathException - if the attribute is invalid.

getApplicableModes

public java.util.Set<Mode> getApplicableModes()
                                       throws XPathException

Get the modes to which this template rule applies

Returns:

the set of modes to which it applies

Throws:

XPathException - should not happen

isOmniMode

public boolean isOmniMode()
                   throws XPathException

Ask whether this is a template rule with mode="#all

Throws:

XPathException

validate

public void validate(ComponentDeclaration decl)
              throws XPathException

Description copied from class: StyleElement

Check that the stylesheet element is valid. This is called once for each element, after the entire tree has been built. As well as validation, it can perform first-time initialisation. The default implementation does nothing; it is normally overriden in subclasses.

Overrides:

validate in class StyleElement

Parameters:

decl - the declaration to be validated

Throws:

XPathException - if any error is found during validation

validateSubtree

public void validateSubtree(ComponentDeclaration decl,
                            boolean excludeStylesheet)
                     throws XPathException

Description copied from class: StyleElement

Recursive walk through the stylesheet to validate all nodes

Overrides:

validateSubtree in class StyleElement

Parameters:

decl - the declaration to be validated

excludeStylesheet - true if the XSLStylesheet element is to be excluded

Throws:

XPathException - if validation fails

index

public void index(ComponentDeclaration decl,
                  PrincipalStylesheetModule top)
           throws XPathException

Description copied from class: StyleElement

Method supplied by declaration elements to add themselves to a stylesheet-level index

Overrides:

index in class StyleElement

Parameters:

decl - the Declaration being indexed. (This corresponds to the StyleElement object except in cases where one module is imported several times with different precedence.)

top - represents the outermost XSLStylesheet or XSLPackage element

Throws:

XPathException - if any error is encountered

markTailCalls

public boolean markTailCalls()

Mark tail-recursive calls on templates and functions.

Overrides:

markTailCalls in class StyleElement

Returns:

true if one or more tail calls were identified

compileDeclaration

public void compileDeclaration(Compilation compilation,
                               ComponentDeclaration decl)
                        throws XPathException

Compile: creates the executable form of the template

Overrides:

compileDeclaration in class StyleElement

Parameters:

compilation - the compilation episode

decl - the containing top-level declaration, for example xsl:function or xsl:template

Throws:

XPathException - if compilation fails

compileTemplateRule

public void compileTemplateRule(Compilation compilation,
                                Expression body,
                                ComponentDeclaration decl)

jitCompile

public void jitCompile(Compilation compilation,
                       ComponentDeclaration decl)
                throws XPathException

Code executed when the template is first executed under JIT. If the template is defined in several modes, then this may be called several times, but it only does anything the first time. Mode-specific processing is done in the TemplateRuleInitializer.

Parameters:

compilation - the compilation episode

decl - the template rule declaration

Throws:

XPathException - if anything goes wrong

register

public void register(ComponentDeclaration declaration)
              throws XPathException

Registers the template rule with each Mode that it belongs to.

Parameters:

declaration - Associates this template with a stylesheet module (in principle an xsl:template element can be in a document that is imported more than once; these are separate declarations)

Throws:

XPathException - if a failure occurs

allocatePatternSlotNumbers

public void allocatePatternSlotNumbers()

Allocate slot numbers to any local variables declared within a predicate within the match pattern

optimize

public void optimize(ComponentDeclaration declaration)
              throws XPathException

This method is a bit of a misnomer, because it does more than invoke optimization of the template body. In particular, it also registers the template rule with each Mode that it belongs to.

Specified by:

optimize in interface StylesheetComponent

Parameters:

declaration - Associates this template with a stylesheet module (in principle an xsl:template element can be in a document that is imported more than once; these are separate declarations)

Throws:

XPathException - if errors are found

getContextItemTypeForTemplateRule

public ItemType getContextItemTypeForTemplateRule()
                                           throws XPathException

Throws:

XPathException

generateByteCode

public void generateByteCode(Optimizer opt)
                      throws XPathException

Generate byte code for the template (if appropriate)

Specified by:

generateByteCode in interface StylesheetComponent

Parameters:

opt - the optimizer

Throws:

XPathException - if byte code generation fails

getSlotManager

public SlotManager getSlotManager()

Get associated Procedure (for details of stack frame)

Specified by:

getSlotManager in interface StylesheetComponent

Returns:

the associated SlotManager object

getCompiledNamedTemplate

public NamedTemplate getCompiledNamedTemplate()

Get the compiled template

Returns:

the compiled template

getConstructType

public int getConstructType()

Get the type of construct. This will be a constant in class LocationKind. This method is part of the InstructionInfo interface

Overrides:

getConstructType in class StyleElement

getMatch

public Pattern getMatch()

getTemplateRulesByMode

public java.util.Map<StructuredQName,TemplateRule> getTemplateRulesByMode()

getSequenceNumber

protected final long getSequenceNumber()

Get the node sequence number (in document order). Sequence numbers are monotonic but not consecutive. In the current implementation, parent nodes (elements and document nodes) have a zero least-significant word, while namespaces, attributes, text nodes, comments, and PIs have the top word the same as their owner and the bottom half reflecting their relative position. For nodes added by XQuery Update, the sequence number is -1L

Overrides:

getSequenceNumber in class NodeImpl

Returns:

the sequence number if there is one, or -1L otherwise.

getRawSequenceNumber

protected final int getRawSequenceNumber()

setRawSequenceNumber

protected final void setRawSequenceNumber(int seq)

setChildren

protected final void setChildren(java.lang.Object children)

Set the children of this node

Parameters:

children - null if there are no children, a single NodeInfo if there is one child, an array of NodeInfo if there are multiple children

hasChildNodes

public final boolean hasChildNodes()

Determine if the node has any children.

Specified by:

hasChildNodes in interface NodeInfo

Overrides:

hasChildNodes in class NodeImpl

Returns:

true if the node has any children, false if the node has no children.

getNumberOfChildren

public final int getNumberOfChildren()

Determine how many children the node has

Returns:

the number of children of this parent node

iterateChildren

protected final AxisIterator iterateChildren(NodeTest test)

Get an enumeration of the children of this node

Parameters:

test - A NodeTest to be satisfied by the child nodes, or null if all child node are to be returned

Returns:

an iterator over the children of this node

getFirstChild

public final NodeImpl getFirstChild()

Get the first child node of the element

Specified by:

getFirstChild in interface SteppingNode<NodeImpl>

Overrides:

getFirstChild in class NodeImpl

Returns:

the first child node of the required type, or null if there are no children

getLastChild

public final NodeImpl getLastChild()

Get the last child node of the element

Overrides:

getLastChild in class NodeImpl

Returns:

the last child of the element, or null if there are no children

getNthChild

protected final NodeImpl getNthChild(int n)

Get the nth child node of the element (numbering from 0)

Parameters:

n - identifies the required child

Returns:

the last child of the element, or null if there is no n'th child

removeChild

protected void removeChild(NodeImpl child)

Remove a given child

Parameters:

child - the child to be removed

getStringValue

public java.lang.String getStringValue()

Return the string-value of the node, that is, the concatenation of the character content of all descendent elements and text nodes.

Returns:

the accumulated character content of the element, including descendant elements.

See Also:

Item.getStringValueCS()

getStringValueCS

public java.lang.CharSequence getStringValueCS()

Description copied from class: NodeImpl

Get the value of the item as a CharSequence. This is in some cases more efficient than the version of the method that returns a String.

Specified by:

getStringValueCS in interface GroundedValue<NodeInfo>

Specified by:

getStringValueCS in interface Item<NodeInfo>

Overrides:

getStringValueCS in class NodeImpl

Returns:

the string value of the item

See Also:

Item.getStringValue()

addChild

protected void addChild(NodeImpl node,
                        int index)

Add a child node to this node. For system use only. Note: normalizing adjacent text nodes is the responsibility of the caller.

Parameters:

node - the node to be added as a child of this node. This must be an instance of NodeImpl. It will be modified as a result of this call (by setting its parent property and sibling position)

index - the position where the child is to be added

insertChildren

public void insertChildren(NodeInfo[] source,
                           boolean atStart,
                           boolean inherit)

Insert a sequence of nodes as children of this node.

This method takes no action unless the target node is a document node or element node. It also takes no action in respect of any supplied nodes that are not elements, text nodes, comments, or processing instructions.

The supplied nodes will form the new children. Adjacent text nodes will be merged, and zero-length text nodes removed. The supplied nodes may be modified in situ, for example to change their parent property and to add namespace bindings, or they may be copied, at the discretion of the implementation.

Specified by:

insertChildren in interface MutableNodeInfo

Overrides:

insertChildren in class NodeImpl

Parameters:

source - the nodes to be inserted. The implementation determines what implementation classes of node it will accept; this implementation will accept text, comment, and processing instruction nodes belonging to any implementation, but elements must be instances of ElementImpl. The supplied nodes will be modified in situ, for example to change their parent property and to add namespace bindings, if they are instances of ElementImpl; otherwise they will be copied. If the nodes are copied, then on return the supplied source array will contain the copy rather than the original.

atStart - true if the new nodes are to be inserted before existing children; false if they are to be inserted after existing children

inherit - true if the inserted nodes are to inherit the namespaces of their new parent; false if such namespaces are to be undeclared

Throws:

java.lang.IllegalArgumentException - if the supplied nodes use a node implementation that this implementation does not accept.

insertChildrenAt

protected void insertChildrenAt(NodeInfo[] source,
                                int index,
                                boolean inherit)

Insert children before or after a given existing child

Parameters:

source - the children to be inserted. We allow any kind of text, comment, or processing instruction node, but element nodes must be instances of this NodeInfo implementation.

index - the position before which they are to be inserted: 0 indicates insertion before the first child, 1 insertion before the second child, and so on.

inherit - true if the inserted nodes are to inherit the namespaces that are in-scope for their new parent; false if such namespaces should be undeclared on the children

replaceChildrenAt

protected void replaceChildrenAt(NodeInfo[] source,
                                 int index,
                                 boolean inherit)

Replace child at a given index by new children

Parameters:

source - the children to be inserted

index - the position at which they are to be inserted: 0 indicates replacement of the first child, replacement of the second child, and so on. The effect is undefined if index is out of range

inherit - set to true if the new child elements are to inherit the in-scope namespaces of their new parent

Throws:

java.lang.IllegalArgumentException - if any of the replacement nodes is not an element, text, comment, or processing instruction node

compact

public void compact(int size)

Compact the space used by this node

Parameters:

size - the number of actual children