Package com.google.javascript.jscomp

Class ReferenceCollectingCallback

java.lang.Object

com.google.javascript.jscomp.ReferenceCollectingCallback

All Implemented Interfaces:

CompilerPass, HotSwapCompilerPass, NodeTraversal.Callback, NodeTraversal.ScopedCallback, StaticSymbolTable<Var,Reference>

public final class ReferenceCollectingCallback
extends java.lang.Object
implements NodeTraversal.ScopedCallback, HotSwapCompilerPass, StaticSymbolTable<Var,Reference>

A helper class for passes that want to access all information about where a variable is referenced and declared at once and then make a decision as to how it should be handled, possibly inlining, reordering, or generating warnings. Callers do this by providing ReferenceCollectingCallback.Behavior and then calling process(Node, Node).

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	ReferenceCollectingCallback.Behavior	Way for callers to add specific behavior during traversal that utilizes the built-up reference information.

Constructor Summary

Constructors

Constructor	Description
ReferenceCollectingCallback(AbstractCompiler compiler, ReferenceCollectingCallback.Behavior behavior, com.google.javascript.jscomp.ScopeCreator creator)	Constructor initializes block stack.

Method Summary

Modifier and Type	Method	Description
void	enterScope(NodeTraversal t)	Updates block stack and invokes any additional behavior.
void	exitScope(NodeTraversal t)	Updates block stack and invokes any additional behavior.
java.lang.Iterable<Var>	getAllSymbols()	Gets the variables that were referenced in this callback.
ReferenceCollection	getReferences(Var v)	Gets the reference collection for the given variable.
Scope	getScope(Var var)	Returns the scope for a given symbol.
void	hotSwapScript(Node scriptRoot, Node originalRoot)	Same as process but only runs on a part of AST associated to one script.
void	process(Node root)
void	process(Node externs, Node root)	Convenience method for running this pass over a tree with this class as a callback.
boolean	shouldTraverse(NodeTraversal nodeTraversal, Node n, Node parent)	Updates block stack.
void	visit(NodeTraversal t, Node n, Node parent)	For each node, update the block stack and reference collection as appropriate.

Methods inherited from class java.lang.Object

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

Constructor Detail

ReferenceCollectingCallback

public ReferenceCollectingCallback(AbstractCompiler compiler,
                                   ReferenceCollectingCallback.Behavior behavior,
                                   com.google.javascript.jscomp.ScopeCreator creator)

Constructor initializes block stack.

Method Detail

process

public void process(Node externs,
                    Node root)

Convenience method for running this pass over a tree with this class as a callback.

Specified by:

process in interface CompilerPass

Parameters:

externs - Top of external JS tree

root - Top of JS tree

process

public void process(Node root)

hotSwapScript

public void hotSwapScript(Node scriptRoot,
                          Node originalRoot)

Same as process but only runs on a part of AST associated to one script.

Specified by:

hotSwapScript in interface HotSwapCompilerPass

Parameters:

scriptRoot - Root node corresponding to the file that is modified, should be of type Token.SCRIPT.

originalRoot - Root node corresponding to the original version of the file that is modified. Should be of type token.SCRIPT.

getAllSymbols

public java.lang.Iterable<Var> getAllSymbols()

Gets the variables that were referenced in this callback.

Specified by:

getAllSymbols in interface StaticSymbolTable<Var,Reference>

getScope

public Scope getScope(Var var)

Description copied from interface: StaticSymbolTable

Returns the scope for a given symbol.

Specified by:

getScope in interface StaticSymbolTable<Var,Reference>

getReferences

public ReferenceCollection getReferences(Var v)

Gets the reference collection for the given variable.

Specified by:

getReferences in interface StaticSymbolTable<Var,Reference>

visit

public void visit(NodeTraversal t,
                  Node n,
                  Node parent)

For each node, update the block stack and reference collection as appropriate.

Specified by:

visit in interface NodeTraversal.Callback

Parameters:

t - The current traversal.

n - The current node.

parent - The parent of the current node.

enterScope

public void enterScope(NodeTraversal t)

Updates block stack and invokes any additional behavior.

Specified by:

enterScope in interface NodeTraversal.ScopedCallback

exitScope

public void exitScope(NodeTraversal t)

Updates block stack and invokes any additional behavior.

Specified by:

exitScope in interface NodeTraversal.ScopedCallback

shouldTraverse

public boolean shouldTraverse(NodeTraversal nodeTraversal,
                              Node n,
                              Node parent)

Updates block stack.

Specified by:

shouldTraverse in interface NodeTraversal.Callback

Parameters:

nodeTraversal - The current traversal.

n - The current node.

parent - The parent of the current node.

Returns:

whether the children of this node should be visited