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; 020 021 import java.io.UnsupportedEncodingException; 022 import java.nio.charset.Charset; 023 024 /** 025 * Abstract base class for Layouts that result in a String. 026 */ 027 public abstract class AbstractStringLayout extends AbstractLayout<String> { 028 029 /** 030 * The charset of the formatted message. 031 */ 032 private final Charset charset; 033 034 private final StringEncoder encoder; 035 036 protected AbstractStringLayout(Charset charset) { 037 this.charset = charset; 038 boolean useClass = false; 039 try { 040 if (String.class.getMethod("getBytes", new Class[] {Charset.class}) != null) { 041 useClass = true; 042 } 043 } catch (NoSuchMethodException ex) { 044 // Not JDK 6 or greater. 045 } 046 encoder = useClass ? new ClassEncoder() : new NameEncoder(); 047 } 048 049 /** 050 * Formats the Log Event as a byte array. 051 * 052 * @param event The Log Event. 053 * @return The formatted event as a byte array. 054 */ 055 public byte[] toByteArray(LogEvent event) { 056 return encoder.getBytes(toSerializable(event)); 057 } 058 059 protected Charset getCharset() { 060 return charset; 061 } 062 063 /** 064 * Encoder interface to support Java 5 and Java 6+. 065 */ 066 private interface StringEncoder { 067 068 byte[] getBytes(String str); 069 } 070 071 /** 072 * JDK 6 or greater. 073 */ 074 private class ClassEncoder implements StringEncoder { 075 public byte[] getBytes(String str) { 076 return str.getBytes(charset); 077 } 078 } 079 080 /** 081 * JDK 5. 082 */ 083 private class NameEncoder implements StringEncoder { 084 public byte[] getBytes(String str) { 085 try { 086 return str.getBytes(charset.name()); 087 } catch (UnsupportedEncodingException ex) { 088 // This shouldn't ever happen since an invalid Charset would never have been created. 089 return str.getBytes(); 090 } 091 } 092 } 093 }