Apache Log4j API provides the interface that applications should code to and provides the adapter components required for implementers to create a logging implementation. Apache Log4j API is a required module to use Apache Log4j.

Bytecode (Java 8) for Apache Log4j API is provided in a separate JAR file like log4j-api-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 API 2.14.1 below.

⏎ org/apache/logging/log4j/util/ProcessIdUtil.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.util;

import java.io.File;
import java.io.IOException;
import java.lang.reflect.Method;

/**
 * @Since 2.9
 */
public class ProcessIdUtil {

    public static final String DEFAULT_PROCESSID = "-";

    public static String getProcessId() {
        try {
            // LOG4J2-2126 use reflection to improve compatibility with Android Platform which does not support JMX extensions
            final Class<?> managementFactoryClass = Class.forName("java.lang.management.ManagementFactory");
            final Method getRuntimeMXBean = managementFactoryClass.getDeclaredMethod("getRuntimeMXBean");
            final Class<?> runtimeMXBeanClass = Class.forName("java.lang.management.RuntimeMXBean");
            final Method getName = runtimeMXBeanClass.getDeclaredMethod("getName");

            final Object runtimeMXBean = getRuntimeMXBean.invoke(null);
            final String name = (String) getName.invoke(runtimeMXBean);
            //String name = ManagementFactory.getRuntimeMXBean().getName(); //JMX not allowed on Android
            return name.split("@")[0]; // likely works on most platforms
        } catch (final Exception ex) {
            try {
                return new File("/proc/self").getCanonicalFile().getName(); // try a Linux-specific way
            } catch (final IOException ignoredUseDefault) {
                // Ignore exception.
            }
        }
        return DEFAULT_PROCESSID;
    }
}

⏎ org/apache/logging/log4j/util/ProcessIdUtil.java

Or download all of them as a single archive file:

File name: log4j-api-2.14.1-sources.jar
File size: 264773 bytes
Release date: 2021-03-06
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