co.elastic.logging.log4j2.MultiFormatHandler Maven / Gradle / Ivy
/*-
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* Java ECS logging
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* Copyright (C) 2019 - 2020 Elastic and contributors
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*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
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package co.elastic.logging.log4j2;
import org.apache.logging.log4j.message.MultiformatMessage;
import org.apache.logging.log4j.util.MultiFormatStringBuilderFormattable;
interface MultiFormatHandler {
void formatJsonTo(MultiformatMessage message, StringBuilder builder);
class Resolver {
static MultiFormatHandler resolve() {
try {
Class.forName("org.apache.logging.log4j.util.MultiFormatStringBuilderFormattable");
return (MultiFormatHandler) Class.forName("co.elastic.logging.log4j2.MultiFormatHandler$MultiFormatStringBuilderFormattableAware").getEnumConstants()[0];
} catch (Exception ignore) {
} catch (LinkageError ignore) {
}
return ForLegacyLog4j.INSTANCE;
}
}
/**
* For log4j2 {@code >=} 2.10
* Never reference directly in prod code so avoid linkage errors when {@link MultiFormatStringBuilderFormattable} is not available
*/
enum MultiFormatStringBuilderFormattableAware implements MultiFormatHandler {
INSTANCE;
private static final String[] JSON_FORMAT = {"JSON"};
@Override
public void formatJsonTo(MultiformatMessage message, StringBuilder builder) {
if (message instanceof MultiFormatStringBuilderFormattable) {
((MultiFormatStringBuilderFormattable) message).formatTo(JSON_FORMAT, builder);
} else {
builder.append(message.getFormattedMessage(JSON_FORMAT));
}
}
}
/**
* Fallback for log4j2 {@code <} 2.10
*/
enum ForLegacyLog4j implements MultiFormatHandler {
INSTANCE;
private static final String[] JSON_FORMAT = {"JSON"};
@Override
public void formatJsonTo(MultiformatMessage message, StringBuilder builder) {
builder.append(message.getFormattedMessage(JSON_FORMAT));
}
}
}