Package com.google.javascript.jscomp

Class ControlFlowGraph.AbstractCfgNodeTraversalCallback

java.lang.Object

com.google.javascript.jscomp.ControlFlowGraph.AbstractCfgNodeTraversalCallback

All Implemented Interfaces:

NodeTraversal.Callback

Enclosing class:

ControlFlowGraph<N>

public abstract static class ControlFlowGraph.AbstractCfgNodeTraversalCallback
extends java.lang.Object
implements NodeTraversal.Callback

Abstract callback to visit a control flow graph node without going into subtrees of the node that are also represented by other control flow graph nodes.

For example, traversing an IF node as root will visit the two subtrees pointed by the ControlFlowGraph.Branch.ON_TRUE and ControlFlowGraph.Branch.ON_FALSE edges.

Constructor Summary

Constructors

Constructor	Description
AbstractCfgNodeTraversalCallback()

Method Summary

Modifier and Type	Method	Description
boolean	shouldTraverse(NodeTraversal nodeTraversal, Node n, Node parent)	Visits a node in preorder (before its children) and decides whether the node and its children should be traversed.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.google.javascript.jscomp.NodeTraversal.Callback

visit

Constructor Detail

AbstractCfgNodeTraversalCallback

public AbstractCfgNodeTraversalCallback()

Method Detail

shouldTraverse

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

Description copied from interface: NodeTraversal.Callback

Visits a node in preorder (before its children) and decides whether the node and its children should be traversed.

If this method returns true, the node will be visited by NodeTraversal.Callback.visit(NodeTraversal, Node, Node) in postorder and its children will be visited by both NodeTraversal.Callback.shouldTraverse(NodeTraversal, Node, Node) in preorder and by NodeTraversal.Callback.visit(NodeTraversal, Node, Node) in postorder.

If this method returns false, the node will not be visited by NodeTraversal.Callback.visit(NodeTraversal, Node, Node) and its children will neither be visited by NodeTraversal.Callback.shouldTraverse(NodeTraversal, Node, Node) nor NodeTraversal.Callback.visit(NodeTraversal, Node, Node).

Siblings are always visited left-to-right.

Implementations can have side-effects (e.g. modify the parse tree). Removing the current node is legal, but removing or reordering nodes above the current node may cause nodes to be visited twice or not at all.

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