com.google.common.flogger.parser.DefaultBraceStyleMessageParser Maven / Gradle / Ivy
/*
* Copyright (C) 2015 The Flogger Authors.
*
* 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 com.google.common.flogger.parser;
import com.google.common.flogger.parameter.BraceStyleParameter;
/**
* Default implementation of the brace style message parser. Note that while the underlying parsing
* mechanism supports the more general "{n,xxx}" form for brace format style logging, the default
* message parser is currently limited to simple indexed place holders (e.g. "{0}"). This class
* could easily be extended to support these trailing format specifiers.
*
* Note also that the implicit place holder syntax used by Log4J (i.e. "{}") is not currently
* supported, however this may change. Currently an unescaped "{}" term in a log message will cause
* a parse error, so adding support for it should not be an issue.
*/
public class DefaultBraceStyleMessageParser extends BraceStyleMessageParser {
private static final BraceStyleMessageParser INSTANCE = new DefaultBraceStyleMessageParser();
public static BraceStyleMessageParser getInstance() {
return INSTANCE;
}
private DefaultBraceStyleMessageParser() {}
@Override
public void parseBraceFormatTerm(
MessageBuilder builder,
int index,
String message,
int termStart,
int formatStart,
int termEnd)
throws ParseException {
if (formatStart != -1) {
// Specify the optional trailing part including leading ':' but excluding trailing '}'.
throw ParseException.withBounds(
"the default brace style parser does not allow trailing format specifiers",
message,
formatStart - 1,
termEnd - 1);
}
builder.addParameter(termStart, termEnd, BraceStyleParameter.of(index));
}
}