Apache Log4j Core Implementation provides the functional components of the logging system. Users are free to create their own plugins and include them in the logging configuration. Apache Log4j Core is a required module to use Apache Log4j.

Bytecode (Java 8) for Apache Log4j Core Implementation is provided in a separate JAR file like log4j-core-2.14.1.jar.

Source Code files for Apache Log4j API are provided in both binary packge like apache-log4j-2.14.1-bin.zip and source package like apache-log4j-2.14.1-src.zip. You can download them at Apache Log4j Website.

You can also browse Source Code files for Apache Log4j Core Implementation 2.14.1 below.

⏎ org/apache/logging/log4j/core/pattern/AnsiEscape.java

/*
 * 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.Arrays;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;

import org.apache.logging.log4j.core.util.Patterns;
import org.apache.logging.log4j.util.EnglishEnums;

/**
 * Converts text into ANSI escape sequences.
 * <p>
 * The names for colors and attributes are standard, but the exact shade/hue/value of colors are not, and depend on the
 * device used to display them.
 * </p>
 */
public enum AnsiEscape {

    /**
     * The Control Sequence Introducer (or Control Sequence Initiator).
     * <p>
     * Most sequences are more than two characters and start with the characters ESC and [ (the left bracket).
     * </p>
     */
    CSI("\u001b["),

    /**
     * Escape suffix.
     */
    SUFFIX("m"),

    /**
     * Escape separator.
     */
    SEPARATOR(";"),

    /**
     * Normal general attribute.
     */
    NORMAL("0"),

    /**
     * Bright general attribute.
     */
    BRIGHT("1"),

    /**
     * Dim general attribute.
     */
    DIM("2"),

    /**
     * Underline general attribute.
     */
    UNDERLINE("3"),

    /**
     * Blink general attribute.
     */
    BLINK("5"),

    /**
     * Reverse general attribute.
     */
    REVERSE("7"),

    /**
     * Normal general attribute.
     */
    HIDDEN("8"),

    /**
     * Black foreground color.
     */
    BLACK("30"),

    /**
     * Black foreground color.
     */
    FG_BLACK("30"),

    /**
     * Red foreground color.
     */
    RED("31"),

    /**
     * Red foreground color.
     */
    FG_RED("31"),

    /**
     * Green foreground color.
     */
    GREEN("32"),

    /**
     * Green foreground color.
     */
    FG_GREEN("32"),

    /**
     * Yellow foreground color.
     */
    YELLOW("33"),

    /**
     * Yellow foreground color.
     */
    FG_YELLOW("33"),

    /**
     * Blue foreground color.
     */
    BLUE("34"),

    /**
     * Blue foreground color.
     */
    FG_BLUE("34"),

    /**
     * Magenta foreground color.
     */
    MAGENTA("35"),

    /**
     * Magenta foreground color.
     */
    FG_MAGENTA("35"),

    /**
     * Cyan foreground color.
     */
    CYAN("36"),

    /**
     * Cyan foreground color.
     */
    FG_CYAN("36"),

    /**
     * White foreground color.
     */
    WHITE("37"),

    /**
     * White foreground color.
     */
    FG_WHITE("37"),

    /**
     * Default foreground color.
     */
    DEFAULT("39"),

    /**
     * Default foreground color.
     */
    FG_DEFAULT("39"),

    /**
     * Black background color.
     */
    BG_BLACK("40"),

    /**
     * Red background color.
     */
    BG_RED("41"),

    /**
     * Green background color.
     */
    BG_GREEN("42"),

    /**
     * Yellow background color.
     */
    BG_YELLOW("43"),

    /**
     * Blue background color.
     */
    BG_BLUE("44"),

    /**
     * Magenta background color.
     */
    BG_MAGENTA("45"),

    /**
     * Cyan background color.
     */
    BG_CYAN("46"),

    /**
     * White background color.
     */
    BG_WHITE("47");

    private static final String DEFAULT_STYLE = CSI.getCode() + SUFFIX.getCode();

    private final String code;

    AnsiEscape(final String code) {
        this.code = code;
    }

    /**
     * Gets the default style.
     *
     * @return the default style
     */
    public static String getDefaultStyle() {
        return DEFAULT_STYLE;
    }

    /**
     * Gets the escape code.
     *
     * @return the escape code.
     */
    public String getCode() {
        return code;
    }

    /**
     * Creates a Map from a source array where values are ANSI escape sequences. The format is:
     *
     * <pre>
     * Key1=Value, Key2=Value, ...
     * </pre>
     *
     * For example:
     *
     * <pre>
     * ERROR=red bold, WARN=yellow bold, INFO=green, ...
     * </pre>
     *
     * You can use whitespace around the comma and equal sign. The names in values MUST come from the
     * {@linkplain AnsiEscape} enum, case is normalized to upper-case internally.
     *
     * @param values the source string to parse.
     * @param dontEscapeKeys do not escape these keys, leave the values as is in the map
     * @return a new map
     */
    public static Map<String, String> createMap(final String values, final String[] dontEscapeKeys) {
        return createMap(values.split(Patterns.COMMA_SEPARATOR), dontEscapeKeys);
    }

    /**
     * Creates a Map from a source array where values are ANSI escape sequences. Each array entry must be in the format:
     *
     * <pre>
     * Key1 = Value
     * </pre>
     *
     * For example:
     *
     * <pre>
     * ERROR=red bold
     * </pre>
     *
     * You can use whitespace around the equal sign and between the value elements. The names in values MUST come from
     * the {@linkplain AnsiEscape} enum, case is normalized to upper-case internally.
     *
     * @param values
     *            the source array to parse.
     * @param dontEscapeKeys
     *            do not escape these keys, leave the values as is in the map
     * @return a new map
     */
    public static Map<String, String> createMap(final String[] values, final String[] dontEscapeKeys) {
        final String[] sortedIgnoreKeys = dontEscapeKeys != null ? dontEscapeKeys.clone() : new String[0];
        Arrays.sort(sortedIgnoreKeys);
        final Map<String, String> map = new HashMap<>();
        for (final String string : values) {
            final String[] keyValue = string.split(Patterns.toWhitespaceSeparator("="));
            if (keyValue.length > 1) {
                final String key = keyValue[0].toUpperCase(Locale.ENGLISH);
                final String value = keyValue[1];
                final boolean escape = Arrays.binarySearch(sortedIgnoreKeys, key) < 0;
                map.put(key, escape ? createSequence(value.split("\\s")) : value);
            }
        }
        return map;
    }

    /**
     * Creates an ANSI escape sequence from the given {@linkplain AnsiEscape} names.
     *
     * @param names
     *            {@linkplain AnsiEscape} names.
     * @return An ANSI escape sequence.
     */
    public static String createSequence(final String... names) {
        if (names == null) {
            return getDefaultStyle();
        }
        final StringBuilder sb = new StringBuilder(AnsiEscape.CSI.getCode());
        boolean first = true;
        for (final String name : names) {
            try {
                final AnsiEscape escape = EnglishEnums.valueOf(AnsiEscape.class, name.trim());
                if (!first) {
                    sb.append(AnsiEscape.SEPARATOR.getCode());
                }
                first = false;
                sb.append(escape.getCode());
            } catch (final Exception ex) {
                // Ignore the error.
            }
        }
        sb.append(AnsiEscape.SUFFIX.getCode());
        return sb.toString();
    }

}

⏎ org/apache/logging/log4j/core/pattern/AnsiEscape.java

Or download all of them as a single archive file:

File name: log4j-core-2.14.1-sources.jar
File size: 1281358 bytes
Release date: 2021-03-06
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