Apache Log4j 1.2 Bridge allows applications coded to use Log4j 1.2 API to use Log4j 2 instead.

Bytecode (Java 8) for Apache Log4j 1.2 Bridge is provided in a separate JAR file like log4j-1.2-api-2.14.1.jar.

Source Code files for Apache Log4j 1.2 Bridge 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 1.2 Bridge 2.14.1 below.

⏎ org/apache/log4j/spi/ThrowableInformation.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.log4j.spi;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.List;

/**
 * Class Description goes here.
 */
public class ThrowableInformation implements java.io.Serializable {

    static final long serialVersionUID = -4748765566864322735L;

    private transient Throwable throwable;
    private Method toStringList;

    public ThrowableInformation(Throwable throwable) {
        this.throwable = throwable;
        Method method = null;
        try {
            Class<?> throwables = Class.forName("org.apache.logging.log4j.core.util.Throwables");
            method = throwables.getMethod("toStringList", Throwable.class);
        } catch (ClassNotFoundException | NoSuchMethodException ex) {
            // Ignore the exception if Log4j-core is not present.
        }
        this.toStringList = method;
    }

    public Throwable getThrowable() {
        return throwable;
    }

    public synchronized String[] getThrowableStrRep() {
        if (toStringList != null && throwable != null) {
            try {
                @SuppressWarnings("unchecked")
                List<String> elements = (List<String>) toStringList.invoke(null, throwable);
                if (elements != null) {
                    return elements.toArray(new String[0]);
                }
            } catch (IllegalAccessException | InvocationTargetException ex) {
                // Ignore the exception.
            }
        }
        return null;
    }
}

⏎ org/apache/log4j/spi/ThrowableInformation.java

Or download all of them as a single archive file:

File name: log4j-1.2-api-2.14.1-sources.jar
File size: 168047 bytes
Release date: 2021-03-06
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