Apache Log4j IOStreams is a Log4j API extension that provides numerous classes from java.io that can either write to a Logger while writing to another OutputStream or Writer, or the contents read by an InputStream or Reader can be wiretapped by a Logger.

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

Source Code files for Apache Log4j IOStreams 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 IOStreams 2.14.1 below.

⏎ org/apache/logging/log4j/io/LoggerFilterOutputStream.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.io;

import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.charset.Charset;

import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.Marker;
import org.apache.logging.log4j.io.internal.InternalFilterOutputStream;
import org.apache.logging.log4j.spi.ExtendedLogger;

/**
 * Logs each line written to a pre-defined level. Can also be configured with a Marker. This class provides an interface
 * that follows the {@link java.io.OutputStream} methods in spirit, but doesn't require output to any external stream.
 * This class should <em>not</em> be used as a stream for an underlying logger unless it's being used as a bridge.
 * Otherwise, infinite loops may occur!
 *
 * @since 2.1
 */
public class LoggerFilterOutputStream extends FilterOutputStream {
    private static final String FQCN = LoggerFilterOutputStream.class.getName();

    private final InternalFilterOutputStream logger;

    protected LoggerFilterOutputStream(final OutputStream out, final Charset charset, final ExtendedLogger logger,
                                       final String fqcn, final Level level, final Marker marker) {
        super(out);
        this.logger = new InternalFilterOutputStream(out, charset, logger, fqcn == null ? FQCN : fqcn,
            level, marker);
    }

    @Override
    public void close() throws IOException {
        this.logger.close();
    }

    @Override
    public void flush() throws IOException {
        this.logger.flush();
    }

    @Override
    public String toString() {
        return LoggerFilterOutputStream.class.getSimpleName() + logger.toString();
    }

    @Override
    public void write(final byte[] b) throws IOException {
        this.logger.write(b);
    }

    @Override
    public void write(final byte[] b, final int off, final int len) throws IOException {
        this.logger.write(b, off, len);
    }

    @Override
    public void write(final int b) throws IOException {
        this.logger.write(b);
    }
}

⏎ org/apache/logging/log4j/io/LoggerFilterOutputStream.java

Or download all of them as a single archive file:

File name: log4j-iostreams-2.14.1-sources.jar
File size: 43404 bytes
Release date: 2021-03-06
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