nodeprinter.java

大名鼎鼎的java动态脚本语言。已经通过了sun的认证

/**
 *
 * Copyright 2005 Jeremy Rayner
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 **/
package org.codehaus.groovy.antlr.treewalker;

import java.io.PrintStream;
import java.util.Stack;

import org.codehaus.groovy.antlr.GroovySourceAST;

/**
 * A simple antlr AST visitor that outputs the tokenName of each node in a pseudo xml style.
 *
 * @author <a href="mailto:[e-mail]">Jeremy Rayner</a>
 * @version $Revision: 1.2 $
 */

public class NodePrinter extends VisitorAdapter {
    private String[] tokenNames;
    private PrintStream out;

    /**
     * A visitor that prints a pseudo xml output to the supplied PrintStream
     * @param out supplied PrintStream to output nodes to
     * @param tokenNames an array of token names to use
     */
    public NodePrinter(PrintStream out,String[] tokenNames) {
        this.tokenNames = tokenNames;
        this.out = out;
    }

    public void visitDefault(GroovySourceAST t,int visit) {
        if (visit == OPENING_VISIT) {
            out.print("<"+ tokenNames[t.getType()] + ">");
        } else {
            out.print("</" + tokenNames[t.getType()] + ">");
        }
    }
}