Package org.antlr.v4.runtime.tree

Interface Tree

All Known Subinterfaces:

ErrorNode, ParseTree, RuleNode, SyntaxTree, TerminalNode

All Known Implementing Classes:

ErrorNodeImpl, GrammarInterpreterRuleContext, InterpreterRuleContext, ParserRuleContext, RuleContext, RuleContextWithAltNum, TerminalNodeImpl

public interface Tree

The basic notion of a tree has a parent, a payload, and a list of children. It is the most abstract interface for all the trees used by ANTLR.

Method Summary

Modifier and Type	Method	Description
Tree	getChild(int i)	If there are children, get the ith value indexed from 0.
int	getChildCount()	How many children are there? If there is none, then this node represents a leaf node.
Tree	getParent()	The parent of this node.
Object	getPayload()	This method returns whatever object represents the data at this note.
String	toStringTree()	Print out a whole tree, not just a node, in LISP format (root child1 .. childN).

Method Detail

getParent

Tree getParent()

The parent of this node. If the return value is null, then this node is the root of the tree.

getPayload

Object getPayload()

This method returns whatever object represents the data at this note. For example, for parse trees, the payload can be a Token representing a leaf node or a RuleContext object representing a rule invocation. For abstract syntax trees (ASTs), this is a Token object.

getChild

Tree getChild(int i)

If there are children, get the ith value indexed from 0.

getChildCount

int getChildCount()

How many children are there? If there is none, then this node represents a leaf node.

toStringTree

String toStringTree()

Print out a whole tree, not just a node, in LISP format (root child1 .. childN). Print just a node if this is a leaf.