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/appender/rolling/action/IfFileName.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.appender.rolling.action;

import java.nio.file.FileSystem;
import java.nio.file.FileSystems;
import java.nio.file.Path;
import java.nio.file.PathMatcher;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.regex.Pattern;

import org.apache.logging.log4j.Logger;
import org.apache.logging.log4j.core.Core;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
import org.apache.logging.log4j.core.config.plugins.PluginElement;
import org.apache.logging.log4j.core.config.plugins.PluginFactory;
import org.apache.logging.log4j.status.StatusLogger;

/**
 * PathCondition that accepts files for deletion if their relative path matches either a glob pattern or a regular
 * expression. If both a regular expression and a glob pattern are specified the glob pattern is used and the regular
 * expression is ignored.
 * <p>
 * The regular expression is a pattern as defined by the {@link Pattern} class. A glob is a simplified pattern
 * expression described in {@link FileSystem#getPathMatcher(String)}.
 */
@Plugin(name = "IfFileName", category = Core.CATEGORY_NAME, printObject = true)
public final class IfFileName implements PathCondition {
    private static final Logger LOGGER = StatusLogger.getLogger();
    private final PathMatcher pathMatcher;
    private final String syntaxAndPattern;
    private final PathCondition[] nestedConditions;

    /**
     * Constructs a FileNameFilter filter. If both a regular expression and a glob pattern are specified the glob
     * pattern is used and the regular expression is ignored.
     *
     * @param glob the baseDir-relative path pattern of the files to delete (may contain '*' and '?' wildcarts)
     * @param regex the regular expression that matches the baseDir-relative path of the file(s) to delete
     * @param nestedConditions nested conditions to evaluate if this condition accepts a path
     */
    private IfFileName(final String glob, final String regex, final PathCondition[] nestedConditions) {
        if (regex == null && glob == null) {
            throw new IllegalArgumentException("Specify either a path glob or a regular expression. "
                    + "Both cannot be null.");
        }
        this.syntaxAndPattern = createSyntaxAndPatternString(glob, regex);
        this.pathMatcher = FileSystems.getDefault().getPathMatcher(syntaxAndPattern);
        this.nestedConditions = nestedConditions == null ? new PathCondition[0] : Arrays.copyOf(nestedConditions,
                nestedConditions.length);
    }

    static String createSyntaxAndPatternString(final String glob, final String regex) {
        if (glob != null) {
            return glob.startsWith("glob:") ? glob : "glob:" + glob;
        }
        return regex.startsWith("regex:") ? regex : "regex:" + regex;
    }

    /**
     * Returns the baseDir-relative path pattern of the files to delete. The returned string takes the form
     * {@code syntax:pattern} where syntax is one of "glob" or "regex" and the pattern is either a {@linkplain Pattern
     * regular expression} or a simplified pattern expression described under "glob" in
     * {@link FileSystem#getPathMatcher(String)}.
     *
     * @return relative path of the file(s) to delete (may contain regular expression or wildcarts)
     */
    public String getSyntaxAndPattern() {
        return syntaxAndPattern;
    }

    public List<PathCondition> getNestedConditions() {
        return Collections.unmodifiableList(Arrays.asList(nestedConditions));
    }

    /*
     * (non-Javadoc)
     *
     * @see org.apache.logging.log4j.core.appender.rolling.action.PathCondition#accept(java.nio.file.Path,
     * java.nio.file.Path, java.nio.file.attribute.BasicFileAttributes)
     */
    @Override
    public boolean accept(final Path basePath, final Path relativePath, final BasicFileAttributes attrs) {
        final boolean result = pathMatcher.matches(relativePath);

        final String match = result ? "matches" : "does not match";
        final String accept = result ? "ACCEPTED" : "REJECTED";
        LOGGER.trace("IfFileName {}: '{}' {} relative path '{}'", accept, syntaxAndPattern, match, relativePath);
        if (result) {
            return IfAll.accept(nestedConditions, basePath, relativePath, attrs);
        }
        return result;
    }

    /*
     * (non-Javadoc)
     *
     * @see org.apache.logging.log4j.core.appender.rolling.action.PathCondition#beforeFileTreeWalk()
     */
    @Override
    public void beforeFileTreeWalk() {
        IfAll.beforeFileTreeWalk(nestedConditions);
    }

    /**
     * Creates a IfFileName condition that returns true if either the specified
     * {@linkplain FileSystem#getPathMatcher(String) glob pattern} or the regular expression matches the relative path.
     * If both a regular expression and a glob pattern are specified the glob pattern is used and the regular expression
     * is ignored.
     *
     * @param glob the baseDir-relative path pattern of the files to delete (may contain '*' and '?' wildcarts)
     * @param regex the regular expression that matches the baseDir-relative path of the file(s) to delete
     * @param nestedConditions nested conditions to evaluate if this condition accepts a path
     * @return A IfFileName condition.
     * @see FileSystem#getPathMatcher(String)
     */
    @PluginFactory
    public static IfFileName createNameCondition(
            // @formatter:off
            @PluginAttribute("glob") final String glob,
            @PluginAttribute("regex") final String regex,
            @PluginElement("PathConditions") final PathCondition... nestedConditions) {
            // @formatter:on
        return new IfFileName(glob, regex, nestedConditions);
    }

    @Override
    public String toString() {
        final String nested = nestedConditions.length == 0 ? "" : " AND " + Arrays.toString(nestedConditions);
        return "IfFileName(" + syntaxAndPattern + nested + ")";
    }
}

⏎ org/apache/logging/log4j/core/appender/rolling/action/IfFileName.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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