001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache license, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the license for the specific language governing permissions and
015 * limitations under the license.
016 */
017package org.apache.logging.log4j.core.pattern;
018
019import org.apache.logging.log4j.core.LogEvent;
020import org.apache.logging.log4j.core.config.Configuration;
021import org.apache.logging.log4j.core.util.OptionConverter;
022import org.apache.logging.log4j.util.PerformanceSensitive;
023
024
025/**
026 * Formats a string literal.
027 */
028@PerformanceSensitive("allocation") // except for replacements
029public final class LiteralPatternConverter extends LogEventPatternConverter implements ArrayPatternConverter {
030
031    /**
032     * String literal.
033     */
034    private final String literal;
035
036    private final Configuration config;
037
038    private final boolean substitute;
039
040    /**
041     * Create a new instance.
042     *
043     * @param config The Configuration.
044     * @param literal string literal.
045     * @param convertBackslashes if {@code true}, backslash characters are treated as escape characters and character
046     *            sequences like "\" followed by "t" (backslash+t) are converted to special characters like '\t' (tab).
047     */
048    public LiteralPatternConverter(final Configuration config, final String literal, final boolean convertBackslashes) {
049        super("Literal", "literal");
050        this.literal = convertBackslashes ? OptionConverter.convertSpecialChars(literal) : literal; // LOG4J2-829
051        this.config = config;
052        substitute = config != null && literal.contains("${");
053    }
054
055    /**
056     * {@inheritDoc}
057     */
058    @Override
059    public void format(final LogEvent event, final StringBuilder toAppendTo) {
060        toAppendTo.append(substitute ? config.getStrSubstitutor().replace(event, literal) : literal);
061    }
062
063    /**
064     * {@inheritDoc}
065     */
066    @Override
067    public void format(final Object obj, final StringBuilder output) {
068        output.append(substitute ? config.getStrSubstitutor().replace(literal) : literal);
069    }
070
071    /**
072     * {@inheritDoc}
073     */
074    @Override
075    public void format(final StringBuilder output, final Object... objects) {
076        output.append(substitute ? config.getStrSubstitutor().replace(literal) : literal);
077    }
078
079    public String getLiteral() {
080        return literal;
081    }
082
083    @Override
084    public boolean isVariable() {
085        return false;
086    }
087
088    @Override
089    public String toString() {
090        return "LiteralPatternConverter[literal=" + literal + ", config=" + config + ", substitute=" + substitute + "]";
091    }
092
093}