org.apache.logging.log4j.core.layout.SerializedLayout Maven / Gradle / Ivy
/*
* 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.layout;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
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.plugins.Plugin;
import org.apache.logging.log4j.core.config.plugins.PluginFactory;
/**
* Formats a {@link LogEvent} in its Java serialized form.
*/
@Plugin(name = "SerializedLayout", category = Node.CATEGORY, elementType = Layout.ELEMENT_TYPE, printObject = true)
public final class SerializedLayout extends AbstractLayout {
private static final long serialVersionUID = 1L;
private static byte[] serializedHeader;
static {
final ByteArrayOutputStream baos = new ByteArrayOutputStream();
try {
final ObjectOutputStream oos = new ObjectOutputStream(baos);
oos.close();
serializedHeader = baos.toByteArray();
} catch (final Exception ex) {
LOGGER.error("Unable to generate Object stream header", ex);
}
}
private SerializedLayout() {
super(null, null);
}
/**
* Formats a {@link org.apache.logging.log4j.core.LogEvent} as a serialized byte array of the LogEvent object.
*
* @param event The LogEvent.
* @return the formatted LogEvent.
*/
@Override
public byte[] toByteArray(final LogEvent event) {
final ByteArrayOutputStream baos = new ByteArrayOutputStream();
try {
final ObjectOutputStream oos = new PrivateObjectOutputStream(baos);
try {
oos.writeObject(event);
oos.reset();
} finally {
oos.close();
}
} catch (final IOException ioe) {
LOGGER.error("Serialization of LogEvent failed.", ioe);
}
return baos.toByteArray();
}
/**
* Returns the LogEvent.
*
* @param event The Logging Event.
* @return The LogEvent.
*/
@Override
public LogEvent toSerializable(final LogEvent event) {
return event;
}
/**
* Creates a SerializedLayout.
* @return A SerializedLayout.
*/
@PluginFactory
public static SerializedLayout createLayout() {
return new SerializedLayout();
}
@Override
public byte[] getHeader() {
return serializedHeader;
}
/**
* SerializedLayout returns a binary stream.
* @return The content type.
*/
@Override
public String getContentType() {
return "application/octet-stream";
}
/**
* The stream header will be written in the Manager so skip it here.
*/
private class PrivateObjectOutputStream extends ObjectOutputStream {
public PrivateObjectOutputStream(final OutputStream os) throws IOException {
super(os);
}
@Override
protected void writeStreamHeader() {
}
}
}