org.antlr.v4.runtime.tree.ParseTree Maven / Gradle / Ivy
/*
* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
* Use of this file is governed by the BSD 3-clause license that
* can be found in the LICENSE.txt file in the project root.
*/
package org.antlr.v4.runtime.tree;
import org.antlr.v4.runtime.Parser;
import org.antlr.v4.runtime.RuleContext;
import org.antlr.v4.runtime.Token;
/** An interface to access the tree of {@link RuleContext} objects created
* during a parse that makes the data structure look like a simple parse tree.
* This node represents both internal nodes, rule invocations,
* and leaf nodes, token matches.
*
* The payload is either a {@link Token} or a {@link RuleContext} object.
*/
public interface ParseTree extends SyntaxTree {
// the following methods narrow the return type; they are not additional methods
@Override
ParseTree getParent();
@Override
ParseTree getChild(int i);
/** Set the parent for this node.
*
* This is not backward compatible as it changes
* the interface but no one was able to create custom
* nodes anyway so I'm adding as it improves internal
* code quality.
*
* One could argue for a restructuring of
* the class/interface hierarchy so that
* setParent, addChild are moved up to Tree
* but that's a major change. So I'll do the
* minimal change, which is to add this method.
*
* @since 4.7
*/
void setParent(RuleContext parent);
/** The {@link ParseTreeVisitor} needs a double dispatch method. */
T accept(ParseTreeVisitor visitor);
/** Return the combined text of all leaf nodes. Does not get any
* off-channel tokens (if any) so won't return whitespace and
* comments if they are sent to parser on hidden channel.
*/
String getText();
/** Specialize toStringTree so that it can print out more information
* based upon the parser.
*/
String toStringTree(Parser parser);
}