nashorn/src/jdk/nashorn/internal/ir/LexicalContextNode.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
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package jdk.nashorn.internal.ir;

import jdk.nashorn.internal.ir.visitor.NodeVisitor;

/**
 * Superclass for nodes that can be part of the lexical context
 * @see LexicalContext
 */
public abstract class LexicalContextNode extends Statement {
    /**
     * Constructor
     *
     * @param lineNumber line number
     * @param token      token
     * @param finish     finish
     */
    protected LexicalContextNode(final int lineNumber, final long token, final int finish) {
        super(lineNumber, token, finish);
    }

    /**
     * Copy constructor
     *
     * @param node source node
     */
    protected LexicalContextNode(final LexicalContextNode node) {
        super(node);
    }

    /**
     * Accept function for the node given a lexical context. It must be prepared
     * to replace itself if present in the lexical context
     *
     * @param lc      lexical context
     * @param visitor node visitor
     *
     * @return new node or same node depending on state change
     */
    protected abstract Node accept(final LexicalContext lc, final NodeVisitor<? extends LexicalContext> visitor);

    @Override
    public Node accept(final NodeVisitor<? extends LexicalContext> visitor) {
        final LexicalContext lc = visitor.getLexicalContext();
        lc.push(this);
        final LexicalContextNode newNode = (LexicalContextNode)accept(lc, visitor);
        return lc.pop(newNode);
    }

    /**
     * Set the symbol and replace in lexical context if applicable
     * @param lc     lexical context
     * @param symbol symbol
     * @return new node if symbol changed
     */
    @Override
    public Node setSymbol(final LexicalContext lc, final Symbol symbol) {
        return Node.replaceInLexicalContext(lc, this, (LexicalContextNode)super.setSymbol(null, symbol));
    }

}