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There is a newer version: 3.0.4
package reflex;

import org.antlr.runtime.CharStream;
import org.antlr.runtime.CommonToken;
import org.antlr.runtime.IntStream;
import org.antlr.runtime.RecognitionException;
import org.antlr.runtime.TokenStream;

public class ErrorHandler {

	public static String displayError(IntStream stream, int line, int position, int length) {
		String[] lines = null;
		StringBuilder sb = new StringBuilder();
		if (stream instanceof CharStream) {
			lines = ((CharStream) stream).substring(0, stream.size() - 1).split("\n");
		} else if (stream instanceof TokenStream) {
			lines = ((TokenStream) stream).toString(0, stream.size() - 1).split("\n");
		}
		
		sb.append(" at line ").append(line).append(" while parsing: \n");

		if (lines != null) {
			int start = Math.max(0, line - 5);
			int end = Math.min(lines.length, line + 5);
			int badline = line - 1;

			for (int i = start; i < end; i++) {
				sb.append(String.format("%5d: %s\n", i + 1, lines[i]));
				if (i == badline) {
					for (int j = 0; j < position + 7; j++)
						sb.append("-");
					for (int j = 0; j <= length; j++)
						sb.append("^");
					sb.append("\n");
				}
			}
		}
		return sb.toString();
	}
	
	static RecognitionException duplicate = null;

	public static String getParserExceptionDetails(RecognitionException e) {
		StringBuilder sb = new StringBuilder();
		if ((duplicate == null) || !duplicate.equals(e)) {
			IntStream stream;
			int line, position, length;
			CommonToken token = (CommonToken) e.token;
			
			String message = e.getMessage();
			if (message != null) {
				sb.append(message);
			} else {
				sb.append("Exception of type ").append(e.getClass().getCanonicalName());
			}

			if (token == null) {
				stream = e.input;
				line = e.line;
				position = e.charPositionInLine;
				length = 1;
			} else {
				sb.append(" at token ").append(token.getText());
				stream = token.getInputStream();
				line = token.getLine();
				position = token.getCharPositionInLine();
				length = token.getStopIndex() - token.getStartIndex();
			}
			
			String error = displayError(stream, line, position, length);
			sb.append(error);
			
			Throwable cause = e.getCause();
			if (cause != null) {
				sb.append("Caused by ").append(cause.getMessage()).append("\n");
			}
		}
		duplicate = e;
		return sb.toString();
	}
}