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/HttpAppender.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;

import java.io.Serializable;
import java.net.URL;
import java.util.Objects;
import java.util.concurrent.TimeUnit;

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.LogEvent;
import org.apache.logging.log4j.core.config.Node;
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.config.plugins.validation.constraints.Required;
import org.apache.logging.log4j.core.net.ssl.SslConfiguration;

/**
 * Sends log events over HTTP.
 */
@Plugin(name = "Http", category = Node.CATEGORY, elementType = Appender.ELEMENT_TYPE, printObject = true)
public final class HttpAppender extends AbstractAppender {

    /**
     * Builds HttpAppender 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<HttpAppender> {

        @PluginBuilderAttribute
        @Required(message = "No URL provided for HttpAppender")
        private URL url;

        @PluginBuilderAttribute
        private String method = "POST";

        @PluginBuilderAttribute
        private int connectTimeoutMillis = 0;

        @PluginBuilderAttribute
        private int readTimeoutMillis = 0;

        @PluginElement("Headers")
        private Property[] headers;

        @PluginElement("SslConfiguration")
        private SslConfiguration sslConfiguration;

        @PluginBuilderAttribute
        private boolean verifyHostname = true;

        @Override
        public HttpAppender build() {
            final HttpManager httpManager = new HttpURLConnectionManager(getConfiguration(),
                    getConfiguration().getLoggerContext(), getName(), url, method, connectTimeoutMillis,
                    readTimeoutMillis, headers, sslConfiguration, verifyHostname);
            return new HttpAppender(getName(), getLayout(), getFilter(), isIgnoreExceptions(), httpManager,
                    getPropertyArray());
        }

        public URL getUrl() {
            return url;
        }

        public String getMethod() {
            return method;
        }

        public int getConnectTimeoutMillis() {
            return connectTimeoutMillis;
        }

        public int getReadTimeoutMillis() {
            return readTimeoutMillis;
        }

        public Property[] getHeaders() {
            return headers;
        }

        public SslConfiguration getSslConfiguration() {
            return sslConfiguration;
        }

        public boolean isVerifyHostname() {
            return verifyHostname;
        }

        public B setUrl(final URL url) {
            this.url = url;
            return asBuilder();
        }

        public B setMethod(final String method) {
            this.method = method;
            return asBuilder();
        }

        public B setConnectTimeoutMillis(final int connectTimeoutMillis) {
            this.connectTimeoutMillis = connectTimeoutMillis;
            return asBuilder();
        }

        public B setReadTimeoutMillis(final int readTimeoutMillis) {
            this.readTimeoutMillis = readTimeoutMillis;
            return asBuilder();
        }

        public B setHeaders(final Property[] headers) {
            this.headers = headers;
            return asBuilder();
        }

        public B setSslConfiguration(final SslConfiguration sslConfiguration) {
            this.sslConfiguration = sslConfiguration;
            return asBuilder();
        }

        public B setVerifyHostname(final boolean verifyHostname) {
            this.verifyHostname = verifyHostname;
            return asBuilder();
        }
    }

    /**
     * @return a builder for a HttpAppender.
     */
    @PluginBuilderFactory
    public static <B extends Builder<B>> B newBuilder() {
        return new Builder<B>().asBuilder();
    }

    private final HttpManager manager;

    private HttpAppender(final String name, final Layout<? extends Serializable> layout, final Filter filter,
            final boolean ignoreExceptions, final HttpManager manager, final Property[] properties) {
        super(name, filter, layout, ignoreExceptions, properties);
        Objects.requireNonNull(layout, "layout");
        this.manager = Objects.requireNonNull(manager, "manager");
    }

    @Override
    public void start() {
        super.start();
        manager.startup();
    }

    @Override
    public void append(final LogEvent event) {
        try {
            manager.send(getLayout(), event);
        } catch (final Exception e) {
            error("Unable to send HTTP in appender [" + getName() + "]", event, e);
        }
    }

    @Override
    public boolean stop(final long timeout, final TimeUnit timeUnit) {
        setStopping();
        boolean stopped = super.stop(timeout, timeUnit, false);
        stopped &= manager.stop(timeout, timeUnit);
        setStopped();
        return stopped;
    }

    @Override
    public String toString() {
        return "HttpAppender{" +
            "name=" + getName() +
            ", state=" + getState() +
            '}';
    }
}

⏎ org/apache/logging/log4j/core/appender/HttpAppender.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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