001 /* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache license, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the license for the specific language governing permissions and 015 * limitations under the license. 016 */ 017 package org.apache.logging.log4j.core.layout; 018 019 import org.apache.logging.log4j.core.LogEvent; 020 import org.apache.logging.log4j.core.config.plugins.Plugin; 021 import org.apache.logging.log4j.core.config.plugins.PluginFactory; 022 023 import java.io.ByteArrayOutputStream; 024 import java.io.IOException; 025 import java.io.ObjectOutputStream; 026 import java.io.OutputStream; 027 028 /** 029 * Format a LogEvent in its serialized form. 030 */ 031 @Plugin(name = "SerializedLayout", type = "Core", elementType = "layout", printObject = true) 032 public final class SerializedLayout extends AbstractLayout<LogEvent> { 033 034 private static byte[] header; 035 036 static { 037 final ByteArrayOutputStream baos = new ByteArrayOutputStream(); 038 try { 039 final ObjectOutputStream oos = new ObjectOutputStream(baos); 040 oos.close(); 041 header = baos.toByteArray(); 042 } catch (final Exception ex) { 043 LOGGER.error("Unable to generate Object stream header", ex); 044 } 045 } 046 047 private SerializedLayout() { 048 } 049 050 /** 051 * Formats a {@link org.apache.logging.log4j.core.LogEvent} in conformance with the log4j.dtd. 052 * 053 * @param event The LogEvent. 054 * @return the formatted LogEvent. 055 */ 056 public byte[] toByteArray(final LogEvent event) { 057 final ByteArrayOutputStream baos = new ByteArrayOutputStream(); 058 try { 059 final ObjectOutputStream oos = new PrivateObjectOutputStream(baos); 060 try { 061 oos.writeObject(event); 062 oos.reset(); 063 } finally { 064 oos.close(); 065 } 066 } catch (final IOException ioe) { 067 LOGGER.error("Serialization of LogEvent failed.", ioe); 068 } 069 return baos.toByteArray(); 070 } 071 072 /** 073 * Returns the LogEvent. 074 * 075 * @param event The Logging Event. 076 * @return The LogEvent. 077 */ 078 public LogEvent toSerializable(final LogEvent event) { 079 return event; 080 } 081 082 /** 083 * Create a SerializedLayout. 084 * @return A SerializedLayout. 085 */ 086 @PluginFactory 087 public static SerializedLayout createLayout() { 088 089 return new SerializedLayout(); 090 } 091 092 @Override 093 public byte[] getHeader() { 094 return header; 095 } 096 097 /** 098 * SerializedLayout returns a binary stream. 099 * @return The content type. 100 */ 101 public String getContentType() { 102 return "application/octet-stream"; 103 } 104 105 /** 106 * The stream header will be written in the Manager so skip it here. 107 */ 108 private class PrivateObjectOutputStream extends ObjectOutputStream { 109 110 public PrivateObjectOutputStream(final OutputStream os) throws IOException { 111 super(os); 112 } 113 114 @Override 115 protected void writeStreamHeader() { 116 } 117 } 118 }