Source Code for Apache Log4j Core Implementation

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 and source package like You can download them at Apache Log4j Website.

You can also browse Source Code files for Apache Log4j Core Implementation 2.14.1 below.



 * 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
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * See the license for the specific language governing permissions and
 * limitations under the license.
package org.apache.logging.log4j.core.jackson;


import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.JsonToken;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.deser.std.StdScalarDeserializer;

 * Copy and edit the Jackson (Apache License 2.0) class to use Log4j attribute names. Does not work as of Jackson 2.3.2.
 * <p>
 * <em>Consider this class private.</em>
 * </p>
public final class Log4jStackTraceElementDeserializer extends StdScalarDeserializer<StackTraceElement> {
    private static final long serialVersionUID = 1L;

     * Constructs a new initialized instance.
    public Log4jStackTraceElementDeserializer() {

    public StackTraceElement deserialize(final JsonParser jp, final DeserializationContext ctxt) throws IOException,
            JsonProcessingException {
        JsonToken t = jp.getCurrentToken();
        // Must get an Object
        if (t == JsonToken.START_OBJECT) {
            String className = null, methodName = null, fileName = null;
            int lineNumber = -1;

            while ((t = jp.nextValue()) != JsonToken.END_OBJECT) {
                final String propName = jp.getCurrentName();
                if ("class".equals(propName)) {
                    className = jp.getText();
                } else if ("file".equals(propName)) {
                    fileName = jp.getText();
                } else if ("line".equals(propName)) {
                    if (t.isNumeric()) {
                        lineNumber = jp.getIntValue();
                    } else {
                        // An XML number always comes in a string since there is no syntax help as with JSON.
                        try {
                            lineNumber = Integer.parseInt(jp.getText().trim());
                        } catch (final NumberFormatException e) {
                            throw JsonMappingException.from(jp, "Non-numeric token (" + t + ") for property 'line'", e);
                } else if ("method".equals(propName)) {
                    methodName = jp.getText();
                } else if ("nativeMethod".equals(propName)) {
                    // no setter, not passed via constructor: ignore
                } else {
                    this.handleUnknownProperty(jp, ctxt, this._valueClass, propName);
            return new StackTraceElement(className, methodName, fileName, lineNumber);
        throw ctxt.mappingException(this._valueClass, t);



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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