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/nosql/NoSqlAppender.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.nosql;

import java.io.Serializable;

import org.apache.logging.log4j.core.Appender;
import org.apache.logging.log4j.core.Filter;
import org.apache.logging.log4j.core.Layout;
import org.apache.logging.log4j.core.appender.AbstractAppender;
import org.apache.logging.log4j.core.appender.db.AbstractDatabaseAppender;
import org.apache.logging.log4j.core.config.Property;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.config.plugins.PluginBuilderAttribute;
import org.apache.logging.log4j.core.config.plugins.PluginBuilderFactory;
import org.apache.logging.log4j.core.config.plugins.PluginElement;
import org.apache.logging.log4j.core.util.Booleans;

/**
 * This Appender writes logging events to a NoSQL database using a configured NoSQL provider. It requires
 * implementations of {@link NoSqlObject}, {@link NoSqlConnection}, and {@link NoSqlProvider} to "know" how to write
 * events to the chosen NoSQL database.
 * <p>
 * For examples on how to write your own NoSQL provider, see the simple source code for the MongoDB and CouchDB
 * providers.
 * </p>
 *
 * @see NoSqlObject
 * @see NoSqlConnection
 * @see NoSqlProvider
 */
@Plugin(name = "NoSql", category = "Core", elementType = Appender.ELEMENT_TYPE, printObject = true)
public final class NoSqlAppender extends AbstractDatabaseAppender<NoSqlDatabaseManager<?>> {

    /**
     * Builds ConsoleAppender instances.
     *
     * @param <B>
     *            The type to build
     */
    public static class Builder<B extends Builder<B>> extends AbstractAppender.Builder<B>
            implements org.apache.logging.log4j.core.util.Builder<NoSqlAppender> {

        @PluginBuilderAttribute("bufferSize")
        private int bufferSize;

        @PluginElement("NoSqlProvider")
        private NoSqlProvider<?> provider;

        @SuppressWarnings("resource")
        @Override
        public NoSqlAppender build() {
            final String name = getName();
            if (provider == null) {
                LOGGER.error("NoSQL provider not specified for appender [{}].", name);
                return null;
            }

            final String managerName = "noSqlManager{ description=" + name + ", bufferSize=" + bufferSize
                    + ", provider=" + provider + " }";

            final NoSqlDatabaseManager<?> manager = NoSqlDatabaseManager.getNoSqlDatabaseManager(managerName,
                    bufferSize, provider);
            if (manager == null) {
                return null;
            }

            return new NoSqlAppender(name, getFilter(), getLayout(), isIgnoreExceptions(), getPropertyArray(), manager);
        }

        /**
         * Sets the buffer size.
         *
         * @param bufferSize
         *            If an integer greater than 0, this causes the appender to buffer log events and flush whenever the
         *            buffer reaches this size.
         * @return this
         */
        public B setBufferSize(final int bufferSize) {
            this.bufferSize = bufferSize;
            return asBuilder();
        }

        /**
         * Sets the provider.
         *
         * @param provider
         *            The NoSQL provider that provides connections to the chosen NoSQL database.
         * @return this
         */
        public B setProvider(final NoSqlProvider<?> provider) {
            this.provider = provider;
            return asBuilder();
        }
    }

    /**
     * Factory method for creating a NoSQL appender within the plugin manager.
     *
     * @param name
     *            The name of the appender.
     * @param ignore
     *            If {@code "true"} (default) exceptions encountered when appending events are logged; otherwise they
     *            are propagated to the caller.
     * @param filter
     *            The filter, if any, to use.
     * @param bufferSize
     *            If an integer greater than 0, this causes the appender to buffer log events and flush whenever the
     *            buffer reaches this size.
     * @param provider
     *            The NoSQL provider that provides connections to the chosen NoSQL database.
     * @return a new NoSQL appender.
     * @deprecated since 2.11.0; use {@link Builder}.
     */
    @SuppressWarnings("resource")
    @Deprecated
    public static NoSqlAppender createAppender(
    // @formatter:off
            final String name,
            final String ignore,
            final Filter filter,
            final String bufferSize,
            final NoSqlProvider<?> provider) {
    // @formatter:on
        if (provider == null) {
            LOGGER.error("NoSQL provider not specified for appender [{}].", name);
            return null;
        }

        final int bufferSizeInt = AbstractAppender.parseInt(bufferSize, 0);
        final boolean ignoreExceptions = Booleans.parseBoolean(ignore, true);

        final String managerName = "noSqlManager{ description=" + name + ", bufferSize=" + bufferSizeInt + ", provider="
                + provider + " }";

        final NoSqlDatabaseManager<?> manager = NoSqlDatabaseManager.getNoSqlDatabaseManager(managerName, bufferSizeInt,
                provider);
        if (manager == null) {
            return null;
        }

        return new NoSqlAppender(name, filter, null, ignoreExceptions, null, manager);
    }

    @PluginBuilderFactory
    public static <B extends Builder<B>> B newBuilder() {
        return new Builder<B>().asBuilder();
    }

    private final String description;

    private NoSqlAppender(final String name, final Filter filter, final Layout<? extends Serializable> layout,
            final boolean ignoreExceptions, final Property[] properties, final NoSqlDatabaseManager<?> manager) {
        super(name, filter, layout, ignoreExceptions, properties, manager);
        this.description = this.getName() + "{ manager=" + this.getManager() + " }";
    }

    @Override
    public String toString() {
        return this.description;
    }
}

⏎ org/apache/logging/log4j/core/appender/nosql/NoSqlAppender.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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