org.springframework.core.log.LogFormatUtils Maven / Gradle / Ivy
/*
* Copyright 2002-2023 the original author or 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
*
* https://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.springframework.core.log;
import java.util.function.Function;
import java.util.regex.Pattern;
import org.apache.commons.logging.Log;
import org.springframework.lang.Nullable;
import org.springframework.util.ObjectUtils;
import org.springframework.util.StringUtils;
/**
* Utility methods for formatting and logging messages.
*
* Mainly for internal use within the framework with Apache Commons Logging,
* typically in the form of the {@code spring-jcl} bridge but also compatible
* with other Commons Logging bridges.
*
* @author Rossen Stoyanchev
* @author Juergen Hoeller
* @since 5.1
*/
public abstract class LogFormatUtils {
private static final Pattern NEWLINE_PATTERN = Pattern.compile("[\n\r]");
private static final Pattern CONTROL_CHARACTER_PATTERN = Pattern.compile("\\p{Cc}");
/**
* Convenience variant of {@link #formatValue(Object, int, boolean)} that
* limits the length of a log message to 100 characters and also replaces
* newline and control characters if {@code limitLength} is set to "true".
* @param value the value to format
* @param limitLength whether to truncate the value at a length of 100
* @return the formatted value
*/
public static String formatValue(@Nullable Object value, boolean limitLength) {
return formatValue(value, (limitLength ? 100 : -1), limitLength);
}
/**
* Format the given value via {@code toString()}, quoting it if it is a
* {@link CharSequence}, truncating at the specified {@code maxLength}, and
* compacting it into a single line when {@code replaceNewLines} is set.
* @param value the value to be formatted
* @param maxLength the max length, after which to truncate, or -1 for unlimited
* @param replaceNewlinesAndControlCharacters whether to replace newline and
* control characters with placeholders
* @return the formatted value
*/
public static String formatValue(
@Nullable Object value, int maxLength, boolean replaceNewlinesAndControlCharacters) {
if (value == null) {
return "";
}
String result;
try {
result = ObjectUtils.nullSafeToString(value);
}
catch (Throwable ex) {
result = ObjectUtils.nullSafeToString(ex);
}
if (maxLength != -1) {
result = StringUtils.truncate(result, maxLength);
}
if (replaceNewlinesAndControlCharacters) {
result = NEWLINE_PATTERN.matcher(result).replaceAll("");
result = CONTROL_CHARACTER_PATTERN.matcher(result).replaceAll("?");
}
if (value instanceof CharSequence) {
result = "\"" + result + "\"";
}
return result;
}
/**
* Use this to log a message with different levels of detail (or different
* messages) at TRACE vs DEBUG log levels. Effectively, a substitute for:
*
* if (logger.isDebugEnabled()) {
* String str = logger.isTraceEnabled() ? "..." : "...";
* if (logger.isTraceEnabled()) {
* logger.trace(str);
* }
* else {
* logger.debug(str);
* }
* }
*
* @param logger the logger to use to log the message
* @param messageFactory function that accepts a boolean set to the value
* of {@link Log#isTraceEnabled()}
*/
public static void traceDebug(Log logger, Function messageFactory) {
if (logger.isDebugEnabled()) {
boolean traceEnabled = logger.isTraceEnabled();
String logMessage = messageFactory.apply(traceEnabled);
if (traceEnabled) {
logger.trace(logMessage);
}
else {
logger.debug(logMessage);
}
}
}
}