Package net.sourceforge.pmd.lang.ast

Interface Node

All Known Subinterfaces:

DFAGraphMethod, QualifiableNode, ScopedNode, SignedNode<N>

All Known Implementing Classes:

AbstractNode

public interface Node

All AST nodes must implement this interface. It provides basic machinery for constructing the parent and child relationships between nodes.

Method Summary

Modifier and Type	Method	Description
java.util.List<? extends Node>	findChildNodesWithXPath(java.lang.String xpathString)	Returns all the nodes matching the xpath expression.
<T> java.util.List<T>	findChildrenOfType(java.lang.Class<T> childType)	Traverses the children to find all the instances of type childType or one of its subclasses.
<T> java.util.List<T>	findDescendantsOfType(java.lang.Class<T> targetType)	Traverses down the tree to find all the descendant instances of type descendantType without crossing find boundaries.
<T> void	findDescendantsOfType(java.lang.Class<T> targetType, java.util.List<T> results, boolean crossFindBoundaries)	Traverses down the tree to find all the descendant instances of type descendantType.
org.w3c.dom.Document	getAsDocument()	Get a DOM Document which contains Elements and Attributes representative of this Node and it's children.
int	getBeginColumn()
int	getBeginLine()
DataFlowNode	getDataFlowNode()
int	getEndColumn()
int	getEndLine()
<T> T	getFirstChildOfType(java.lang.Class<T> childType)	Traverses the children to find the first instance of type childType.
<T> T	getFirstDescendantOfType(java.lang.Class<T> descendantType)	Traverses down the tree to find the first descendant instance of type descendantType without crossing find boundaries.
<T> T	getFirstParentOfAnyType(java.lang.Class<? extends T>... parentTypes)	Gets the first parent that's an instance of any of the given types.
<T> T	getFirstParentOfType(java.lang.Class<T> parentType)	Traverses up the tree to find the first parent instance of type parentType or one of its subclasses.
java.lang.String	getImage()	Returns a string token, usually filled-in by the parser, which describes some textual characteristic of this node.
Node	getNthParent(int n)	Returns the n-th parent or null if there are less than n ancestors.
<T> java.util.List<T>	getParentsOfType(java.lang.Class<T> parentType)	Traverses up the tree to find all of the parent instances of type parentType or one of its subclasses.
java.lang.Object	getUserData()	Get the user data associated with this node.
java.lang.String	getXPathNodeName()	Gets the name of the node that is used to match it with XPath queries.
boolean	hasDescendantMatchingXPath(java.lang.String xpathString)	Checks whether at least one descendant matches the xpath expression.
<T> boolean	hasDescendantOfType(java.lang.Class<T> type)	Finds if this node contains a descendant of the given type without crossing find boundaries.
boolean	hasImageEqualTo(java.lang.String image)	Returns true if this node's image is equal to the given string.
boolean	isFindBoundary()	Returns true if this node is considered a boundary by traversal methods.
void	jjtAddChild(Node child, int index)	This method tells the node to add its argument to the node's list of children.
void	jjtClose()	This method is called after all the child nodes have been added.
Node	jjtGetChild(int index)	This method returns a child node.
int	jjtGetChildIndex()	Gets the index of this node in the children of its parent.
int	jjtGetId()
int	jjtGetNumChildren()	Returns the number of children the node has.
Node	jjtGetParent()	Returns the parent of this node.
void	jjtOpen()	This method is called after the node has been made the current node.
void	jjtSetChildIndex(int index)	Sets the index of this node from the perspective of its parent.
void	jjtSetParent(Node parent)	Sets the parent of this node.
void	remove()	Remove the current node from its parent.
void	removeChildAtIndex(int childIndex)	This method tells the node to remove the child node at the given index from the node's list of children, if any; if not, no changes are done.
void	setDataFlowNode(DataFlowNode dataFlowNode)
void	setImage(java.lang.String image)
void	setUserData(java.lang.Object userData)	Set the user data associated with this node.

Method Detail

jjtOpen

void jjtOpen()

This method is called after the node has been made the current node. It indicates that child nodes can now be added to it.

jjtClose

void jjtClose()

This method is called after all the child nodes have been added.

jjtSetParent

void jjtSetParent(Node parent)

Sets the parent of this node.

Parameters:

parent - The parent

jjtGetParent

Node jjtGetParent()

Returns the parent of this node.

Returns:

The parent of the node

jjtAddChild

void jjtAddChild(Node child,
                 int index)

This method tells the node to add its argument to the node's list of children.

Parameters:

child - The child to add

index - The index to which the child will be added

jjtSetChildIndex

void jjtSetChildIndex(int index)

Sets the index of this node from the perspective of its parent. This means: this.jjtGetParent().jjtGetChild(index) == this.

Parameters:

index - the child index

jjtGetChildIndex

int jjtGetChildIndex()

Gets the index of this node in the children of its parent.

Returns:

The index of the node

jjtGetChild

Node jjtGetChild(int index)

This method returns a child node. The children are numbered from zero, left to right.

Parameters:

index - the child index. Must be nonnegative and less than jjtGetNumChildren().

jjtGetNumChildren

int jjtGetNumChildren()

Returns the number of children the node has.

jjtGetId

int jjtGetId()

getImage

java.lang.String getImage()

Returns a string token, usually filled-in by the parser, which describes some textual characteristic of this node. This is usually an identifier, but you should check that using the Designer. On most nodes though, this method returns null.

setImage

void setImage(java.lang.String image)

hasImageEqualTo

boolean hasImageEqualTo(java.lang.String image)

Returns true if this node's image is equal to the given string.

Parameters:

image - The image to check

getBeginLine

int getBeginLine()

getBeginColumn

int getBeginColumn()

getEndLine

int getEndLine()

getEndColumn

int getEndColumn()

getDataFlowNode

DataFlowNode getDataFlowNode()

setDataFlowNode

void setDataFlowNode(DataFlowNode dataFlowNode)

isFindBoundary

boolean isFindBoundary()

Returns true if this node is considered a boundary by traversal methods. Traversal methods such as getFirstDescendantOfType(Class) don't look past such boundaries by default, which is usually the expected thing to do. For example, in Java, lambdas and nested classes are considered find boundaries.

getNthParent

Node getNthParent(int n)

Returns the n-th parent or null if there are less than n ancestors.

Parameters:

n - how many ancestors to iterate over.

Returns:

the n-th parent or null.

Throws:

java.lang.IllegalArgumentException - if n is negative or zero.

getFirstParentOfType

<T> T getFirstParentOfType(java.lang.Class<T> parentType)

Traverses up the tree to find the first parent instance of type parentType or one of its subclasses.

Type Parameters:

T - The type you want to find

Parameters:

parentType - Class literal of the type you want to find

Returns:

Node of type parentType. Returns null if none found.

getParentsOfType

<T> java.util.List<T> getParentsOfType(java.lang.Class<T> parentType)

Traverses up the tree to find all of the parent instances of type parentType or one of its subclasses. The nodes are ordered deepest-first.

Type Parameters:

T - The type you want to find

Parameters:

parentType - Class literal of the type you want to find

Returns:

List of parentType instances found.

getFirstParentOfAnyType

<T> T getFirstParentOfAnyType(java.lang.Class<? extends T>... parentTypes)

Gets the first parent that's an instance of any of the given types.

Type Parameters:

T - Most specific common type of the parameters

Parameters:

parentTypes - Types to look for

Returns:

The first parent with a matching type. Returns null if there is no such parent

findChildrenOfType

<T> java.util.List<T> findChildrenOfType(java.lang.Class<T> childType)

Traverses the children to find all the instances of type childType or one of its subclasses.

Parameters:

childType - class which you want to find.

Returns:

List of all children of type childType. Returns an empty list if none found.

See Also:

if traversal of the entire tree is needed.

findDescendantsOfType

<T> java.util.List<T> findDescendantsOfType(java.lang.Class<T> targetType)

Traverses down the tree to find all the descendant instances of type descendantType without crossing find boundaries.

Parameters:

targetType - class which you want to find.

Returns:

List of all children of type targetType. Returns an empty list if none found.

findDescendantsOfType

<T> void findDescendantsOfType(java.lang.Class<T> targetType,
                               java.util.List<T> results,
                               boolean crossFindBoundaries)

Traverses down the tree to find all the descendant instances of type descendantType.

Parameters:

targetType - class which you want to find.

results - list to store the matching descendants

crossFindBoundaries - if false, recursion stops for nodes for which isFindBoundary() is true

getFirstChildOfType

<T> T getFirstChildOfType(java.lang.Class<T> childType)

Traverses the children to find the first instance of type childType.

Parameters:

childType - class which you want to find.

Returns:

Node of type childType. Returns null if none found.

See Also:

if traversal of the entire tree is needed.

getFirstDescendantOfType

<T> T getFirstDescendantOfType(java.lang.Class<T> descendantType)

Traverses down the tree to find the first descendant instance of type descendantType without crossing find boundaries.

Parameters:

descendantType - class which you want to find.

Returns:

Node of type descendantType. Returns null if none found.

hasDescendantOfType

<T> boolean hasDescendantOfType(java.lang.Class<T> type)

Finds if this node contains a descendant of the given type without crossing find boundaries.

Parameters:

type - the node type to search

Returns:

true if there is at least one descendant of the given type

findChildNodesWithXPath

java.util.List<? extends Node> findChildNodesWithXPath(java.lang.String xpathString)
                                                throws org.jaxen.JaxenException

Returns all the nodes matching the xpath expression.

Parameters:

xpathString - the expression to check

Returns:

List of all matching nodes. Returns an empty list if none found.

Throws:

org.jaxen.JaxenException - if the xpath is incorrect or fails altogether

hasDescendantMatchingXPath

boolean hasDescendantMatchingXPath(java.lang.String xpathString)

Checks whether at least one descendant matches the xpath expression.

Parameters:

xpathString - the expression to check

Returns:

true if there is a match

getAsDocument

org.w3c.dom.Document getAsDocument()

Get a DOM Document which contains Elements and Attributes representative of this Node and it's children. Essentially a DOM tree representation of the Node AST, thereby allowing tools which can operate upon DOM to also indirectly operate on the AST.

getUserData

java.lang.Object getUserData()

Get the user data associated with this node. By default there is no data, unless it has been set via setUserData(Object).

Returns:

The user data set on this node.

setUserData

void setUserData(java.lang.Object userData)

Set the user data associated with this node.

PMD itself will never set user data onto a node. Nor should any Rule implementation, as the AST nodes are shared between concurrently executing Rules (i.e. it is not thread-safe).

This API is most useful for external applications looking to leverage PMD's robust support for AST structures, in which case application specific annotations on the AST nodes can be quite useful.

Parameters:

userData - The data to set on this node.

remove

void remove()

Remove the current node from its parent.

removeChildAtIndex

void removeChildAtIndex(int childIndex)

This method tells the node to remove the child node at the given index from the node's list of children, if any; if not, no changes are done.

Parameters:

childIndex - The index of the child to be removed

getXPathNodeName

java.lang.String getXPathNodeName()

Gets the name of the node that is used to match it with XPath queries.

Returns:

The XPath node name