/*
* Copyright 2010 NCHOVY
*
* 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.krakenapps.bnf;
public class TracePrinter implements ParserTracer {
private int depth = -2;
@Override
public ParserContext begin(String symbol, int position) {
depth += 2;
pad();
System.out.println("-->begin parse: " + symbol + ", " + position);
return null;
}
@Override
public void error(String symbol, int position) {
pad();
System.out.println("<--error: " + symbol + ", " + position);
depth -= 2;
}
@Override
public void end(String symbol, int nextPosition) {
pad();
System.out.println("<--end parse: " + symbol + " " + nextPosition);
depth -= 2;
}
@Override
public void handle(Rule rule, String token) {
pad();
System.out.println(rule.getClass().getName() + ", " + token);
}
private void pad() {
for (int i = 0; i < depth; i++)
System.out.print(" ");
}
}