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/IfAccumulatedFileCount.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.Path;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;

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 paths after some count threshold is exceeded during the file tree walk.
 */
@Plugin(name = "IfAccumulatedFileCount", category = Core.CATEGORY_NAME, printObject = true)
public final class IfAccumulatedFileCount implements PathCondition {
    private static final Logger LOGGER = StatusLogger.getLogger();
    private final int threshold;
    private int count;
    private final PathCondition[] nestedConditions;

    private IfAccumulatedFileCount(final int thresholdParam, final PathCondition[] nestedConditions) {
        if (thresholdParam <= 0) {
            throw new IllegalArgumentException("Count must be a positive integer but was " + thresholdParam);
        }
        this.threshold = thresholdParam;
        this.nestedConditions = nestedConditions == null ? new PathCondition[0] : Arrays.copyOf(nestedConditions,
                nestedConditions.length);
    }

    public int getThresholdCount() {
        return threshold;
    }

    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 = ++count > threshold;
        final String match = result ? ">" : "<=";
        final String accept = result ? "ACCEPTED" : "REJECTED";
        LOGGER.trace("IfAccumulatedFileCount {}: {} count '{}' {} threshold '{}'", accept, relativePath, count, match,
                threshold);
        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() {
        count = 0;
        IfAll.beforeFileTreeWalk(nestedConditions);
    }

    /**
     * Create an IfAccumulatedFileCount condition.
     *
     * @param threshold The threshold count from which files will be deleted.
     * @return An IfAccumulatedFileCount condition.
     */
    @PluginFactory
    public static IfAccumulatedFileCount createFileCountCondition(
            // @formatter:off
            @PluginAttribute(value = "exceeds", defaultInt = Integer.MAX_VALUE) final int threshold,
            @PluginElement("PathConditions") final PathCondition... nestedConditions) {
            // @formatter:on

        if (threshold == Integer.MAX_VALUE) {
            LOGGER.error("IfAccumulatedFileCount invalid or missing threshold value.");
        }
        return new IfAccumulatedFileCount(threshold, nestedConditions);
    }

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

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