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/config/builder/impl/DefaultComponentBuilder.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.config.builder.impl;

import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.core.config.Configuration;
import org.apache.logging.log4j.core.config.builder.api.Component;
import org.apache.logging.log4j.core.config.builder.api.ComponentBuilder;
import org.apache.logging.log4j.core.config.builder.api.ConfigurationBuilder;

/**
 * Generic component that captures attributes and Components in preparation for assembling the Appender's
 * Component.
 *
 * @since 2.4
 */
class DefaultComponentBuilder<T extends ComponentBuilder<T>, CB extends ConfigurationBuilder<? extends Configuration>>
        implements ComponentBuilder<T> {

    private final CB builder;
    private final String type;
    private final Map<String, String> attributes = new LinkedHashMap<>();
    private final List<Component> components = new ArrayList<>();
    private final String name;
    private final String value;

    public DefaultComponentBuilder(final CB builder, final String type) {
        this(builder, null, type, null);
    }

    public DefaultComponentBuilder(final CB builder, final String name, final String type) {
        this(builder, name, type, null);
    }

    public DefaultComponentBuilder(final CB builder, final String name, final String type,
            final String value) {
        this.type = type;
        this.builder = builder;
        this.name = name;
        this.value = value;
    }

    @Override
    public T addAttribute(final String key, final boolean value) {
        return put(key, Boolean.toString(value));
    }

    @Override
    public T addAttribute(final String key, final Enum<?> value) {
        return put(key, value.name());
    }

    @Override
    public T addAttribute(final String key, final int value) {
        return put(key, Integer.toString(value));
    }


    @Override
    public T addAttribute(final String key, final Level level) {
        return put(key, level.toString());
    }

    @Override
    public T addAttribute(final String key, final Object value) {
        return put(key, value.toString());
    }


    @Override
    public T addAttribute(final String key, final String value) {
        return put(key, value);
    }

    @Override
    @SuppressWarnings("unchecked")
    public T addComponent(final ComponentBuilder<?> builder) {
        components.add(builder.build());
        return (T) this;
    }

    @Override
    public Component build() {
        final Component component = new Component(type, name, value);
        component.getAttributes().putAll(attributes);
        component.getComponents().addAll(components);
        return component;
    }

    @Override
    public CB getBuilder() {
        return builder;
    }

    @Override
    public String getName() {
        return name;
    }

    @SuppressWarnings("unchecked")
    protected T put(final String key, final String value) {
        attributes.put(key, value);
        return (T) this;
    }
}

⏎ org/apache/logging/log4j/core/config/builder/impl/DefaultComponentBuilder.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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