org.apache.logging.log4j.core.pattern.StyleConverter Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.logging.log4j.core.pattern;
import java.util.List;
import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.config.Configuration;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.layout.PatternLayout;
import org.apache.logging.log4j.core.util.Patterns;
/**
* Style pattern converter. Adds ANSI color styling to the result of the enclosed pattern.
*/
@Plugin(name = "style", category = PatternConverter.CATEGORY)
@ConverterKeys({ "style" })
public final class StyleConverter extends LogEventPatternConverter implements AnsiConverter {
/**
* Gets an instance of the class.
*
* @param config
* The current Configuration.
* @param options
* pattern options, may be null. If first element is "short", only the first line of the throwable will
* be formatted.
* @return instance of class.
*/
public static StyleConverter newInstance(final Configuration config, final String[] options) {
if (options.length < 1) {
LOGGER.error("Incorrect number of options on style. Expected at least 1, received " + options.length);
return null;
}
if (options[0] == null) {
LOGGER.error("No pattern supplied on style");
return null;
}
if (options[1] == null) {
LOGGER.error("No style attributes provided");
return null;
}
final PatternParser parser = PatternLayout.createPatternParser(config);
final List formatters = parser.parse(options[0]);
final String style = AnsiEscape.createSequence(options[1].split(Patterns.COMMA_SEPARATOR));
final boolean noConsoleNoAnsi = options.length > 2
&& (PatternParser.NO_CONSOLE_NO_ANSI + "=true").equals(options[2]);
final boolean hideAnsi = noConsoleNoAnsi && System.console() == null;
return new StyleConverter(formatters, style, hideAnsi);
}
private final List patternFormatters;
private final boolean noAnsi;
private final String style;
private final String defaultStyle;
/**
* Constructs the converter.
*
* @param patternFormatters
* The PatternFormatters to generate the text to manipulate.
* @param style
* The style that should encapsulate the pattern.
* @param noAnsi
* If true, do not output ANSI escape codes.
*/
private StyleConverter(final List patternFormatters, final String style, final boolean noAnsi) {
super("style", "style");
this.patternFormatters = patternFormatters;
this.style = style;
this.defaultStyle = AnsiEscape.getDefaultStyle();
this.noAnsi = noAnsi;
}
/**
* {@inheritDoc}
*/
@Override
public void format(final LogEvent event, final StringBuilder toAppendTo) {
final StringBuilder buf = new StringBuilder();
for (final PatternFormatter formatter : patternFormatters) {
formatter.format(event, buf);
}
if (buf.length() > 0) {
if (noAnsi) {
// faster to test and do this than setting style and defaultStyle to empty strings.
toAppendTo.append(buf.toString());
} else {
toAppendTo.append(style).append(buf.toString()).append(defaultStyle);
}
}
}
@Override
public boolean handlesThrowable() {
for (final PatternFormatter formatter : patternFormatters) {
if (formatter.handlesThrowable()) {
return true;
}
}
return false;
}
/**
* Returns a String suitable for debugging.
*
* @return a String suitable for debugging.
*/
@Override
public String toString() {
final StringBuilder sb = new StringBuilder();
sb.append(super.toString());
sb.append("[style=");
sb.append(style);
sb.append(", defaultStyle=");
sb.append(defaultStyle);
sb.append(", patternFormatters=");
sb.append(patternFormatters);
sb.append(", noAnsi=");
sb.append(noAnsi);
sb.append(']');
return sb.toString();
}
}