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 */ 017package org.apache.logging.log4j.core.layout; 018 019import java.io.Serializable; 020import java.util.HashMap; 021import java.util.Map; 022 023import org.apache.logging.log4j.Logger; 024import org.apache.logging.log4j.core.Layout; 025import org.apache.logging.log4j.status.StatusLogger; 026 027/** 028 * Abstract base class for Layouts. 029 * 030 * @param <T> 031 * The Class that the Layout will format the LogEvent into. 032 */ 033public abstract class AbstractLayout<T extends Serializable> implements Layout<T>, Serializable { 034 035 private static final long serialVersionUID = 1L; 036 037 /** 038 * Allow subclasses access to the status logger without creating another instance. 039 */ 040 protected static final Logger LOGGER = StatusLogger.getLogger(); 041 042 /** 043 * The header to include when the stream is opened. May be null. 044 */ 045 protected final byte[] header; 046 047 /** 048 * The footer to add when the stream is closed. May be null. 049 */ 050 protected final byte[] footer; 051 052 /** 053 * Constructs a layout with an optional header and footer. 054 * 055 * @param header 056 * The header to include when the stream is opened. May be null. 057 * @param footer 058 * The footer to add when the stream is closed. May be null. 059 */ 060 public AbstractLayout(final byte[] header, final byte[] footer) { 061 super(); 062 this.header = header; 063 this.footer = footer; 064 } 065 066 @Override 067 public Map<String, String> getContentFormat() { 068 return new HashMap<String, String>(); 069 } 070 071 /** 072 * Returns the footer, if one is available. 073 * 074 * @return A byte array containing the footer. 075 */ 076 @Override 077 public byte[] getFooter() { 078 return footer; 079 } 080 081 /** 082 * Returns the header, if one is available. 083 * 084 * @return A byte array containing the header. 085 */ 086 @Override 087 public byte[] getHeader() { 088 return header; 089 } 090}