org.checkerframework.dataflow.cfg.node

Class Node

java.lang.Object

org.checkerframework.dataflow.cfg.node.Node

Direct Known Subclasses:

ArrayAccessNode, ArrayCreationNode, ArrayTypeNode, AssertionErrorNode, AssignmentNode, BinaryOperationNode, CaseNode, ClassDeclarationNode, ClassNameNode, FieldAccessNode, FunctionalInterfaceNode, InstanceOfNode, LambdaResultExpressionNode, LocalVariableNode, MarkerNode, MethodAccessNode, MethodInvocationNode, NarrowingConversionNode, NullChkNode, ObjectCreationNode, PackageNameNode, ParameterizedTypeNode, PrimitiveTypeNode, ReturnNode, StringConcatenateAssignmentNode, StringConversionNode, SuperNode, SynchronizedNode, TernaryExpressionNode, ThisLiteralNode, ThrowNode, TypeCastNode, UnaryOperationNode, ValueLiteralNode, VariableDeclarationNode, WideningConversionNode

public abstract class Node
extends Object

A node in the abstract representation used for Java code inside a basic block.

The following invariants hold:

 block == null || block instanceof RegularBlock || block instanceof ExceptionBlock
 block != null ⇔ block.getNodes().contains(this)
 

 type != null
 tree != null ⇒ node.getType() == InternalUtils.typeOf(node.getTree())
 

Note that two Nodes can be .equals but represent different CFG nodes. Take care to use reference equality, maps that handle identity IdentityHashMap, and sets like IdentityMostlySingleton.

See Also:

IdentityMostlySingleton

Field Summary

Fields

Modifier and Type	Field and Description
protected @Nullable AssignmentContext	assignmentContext The assignment context of this node.
protected @Nullable Block	block The basic block this node belongs to.
protected boolean	inSource Does this node represent a tree that appears in the source code (true) or one that the CFG builder added while desugaring (false).
protected boolean	lvalue Is this node an l-value?
protected TypeMirror	type The type of this node.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Node(TypeMirror type)

Method Summary

Modifier and Type	Method and Description
abstract <R,P> R	accept(NodeVisitor<R,P> visitor, P p) Accept method of the visitor pattern.
@Nullable AssignmentContext	getAssignmentContext() The assignment context for the node.
@Nullable Block	getBlock() Returns the basic block this node belongs to (or null if it represents the parameter of a method).
boolean	getInSource()
abstract Collection<Node>	getOperands() Returns a collection containing all of the operand Nodes of this Node.
Collection<Node>	getTransitiveOperands() Returns a collection containing all of the operand Nodes of this Node, as well as (transitively) the operands of its operands.
abstract @Nullable Tree	getTree() Returns the Tree in the abstract syntax tree, or null if no corresponding tree exists.
TypeMirror	getType() Returns a TypeMirror representing the type of a Node.
boolean	isLValue() Is the node an lvalue or not?
static String	nodeCollectionToString(Collection<? extends Node> nodes) Returns a verbose string representation of a collection of nodes, useful for debugging..
void	setAssignmentContext(AssignmentContext assignmentContext)
void	setBlock(Block b) Set the basic block this node belongs to.
void	setInSource(boolean inSrc)
void	setLValue() Make this node an l-value.
String	toStringDebug() Returns a verbose string representation of this, useful for debugging.

Methods inherited from class java.lang.Object

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

Field Detail

block

protected @Nullable Block block

The basic block this node belongs to. If null, this object represents a method formal parameter.

lvalue

protected boolean lvalue

Is this node an l-value?

assignmentContext

protected @Nullable AssignmentContext assignmentContext

The assignment context of this node. See AssignmentContext.

inSource

protected boolean inSource

Does this node represent a tree that appears in the source code (true) or one that the CFG builder added while desugaring (false).

type

protected final TypeMirror type

The type of this node. For Nodes with Trees, this type is the type of the Tree. Otherwise, it is the type is set by the CFGBuilder.

Constructor Detail

Node

protected Node(TypeMirror type)

Method Detail

getBlock

public @Nullable Block getBlock()

Returns the basic block this node belongs to (or null if it represents the parameter of a method).

Returns:

the basic block this node belongs to (or null if it represents the parameter of a method)

setBlock

public void setBlock(Block b)

Set the basic block this node belongs to.

getTree

@Pure
public abstract @Nullable Tree getTree()

Returns the Tree in the abstract syntax tree, or null if no corresponding tree exists. For instance, this is the case for an ImplicitThisLiteralNode.

Returns:

the corresponding Tree or null.

getType

public TypeMirror getType()

Returns a TypeMirror representing the type of a Node. A Node will always have a type even when it has no Tree.

Returns:

a TypeMirror representing the type of this Node

accept

public abstract <R,P> R accept(NodeVisitor<R,P> visitor,
                               P p)

Accept method of the visitor pattern.

Type Parameters:

R - result type of the operation

P - parameter type

Parameters:

visitor - the visitor to be applied to this node

p - the parameter for this operation

isLValue

@Pure
public boolean isLValue()

Is the node an lvalue or not?

setLValue

public void setLValue()

Make this node an l-value.

getInSource

public boolean getInSource()

setInSource

public void setInSource(boolean inSrc)

getAssignmentContext

public @Nullable AssignmentContext getAssignmentContext()

The assignment context for the node.

setAssignmentContext

public void setAssignmentContext(AssignmentContext assignmentContext)

getOperands

public abstract Collection<Node> getOperands()

Returns a collection containing all of the operand Nodes of this Node.

Returns:

a collection containing all of the operand Nodes of this Node

getTransitiveOperands

public Collection<Node> getTransitiveOperands()

Returns a collection containing all of the operand Nodes of this Node, as well as (transitively) the operands of its operands.

Returns:

a collection containing all of the operand Nodes of this Node, as well as (transitively) the operands of its operands

toStringDebug

public String toStringDebug()

Returns a verbose string representation of this, useful for debugging.

Returns:

a printed representation of this

nodeCollectionToString

public static String nodeCollectionToString(Collection<? extends Node> nodes)

Returns a verbose string representation of a collection of nodes, useful for debugging..

Parameters:

nodes - a collection of nodes to format

Returns:

a printed representation of the given collection