1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache license, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the license for the specific language governing permissions and 15 * limitations under the license. 16 */ 17 package org.apache.logging.log4j.core.pattern; 18 19 import org.apache.logging.log4j.core.LogEvent; 20 import org.apache.logging.log4j.core.config.plugins.Plugin; 21 import org.apache.logging.log4j.message.MapMessage; 22 import org.apache.logging.log4j.message.MapMessage.MapFormat; 23 24 import java.util.Objects; 25 26 /** 27 * Able to handle the contents of the LogEvent's MapMessage and either 28 * output the entire contents of the properties in a similar format to the 29 * java.util.Hashtable.toString(), or to output the value of a specific key 30 * within the Map. 31 */ 32 @Plugin(name = "MapPatternConverter", category = PatternConverter.CATEGORY) 33 @ConverterKeys({ "K", "map", "MAP" }) 34 public final class MapPatternConverter extends LogEventPatternConverter { 35 36 private static final String JAVA_UNQUOTED = MapFormat.JAVA_UNQUOTED.name(); 37 38 /** 39 * Name of property to output. 40 */ 41 private final String key; 42 43 /** 44 * Format to use when no key is provided. 45 * 46 * @see MapFormat 47 * @since 2.11.2 48 */ 49 private final String[] format; 50 51 /** 52 * Private constructor. 53 * 54 * @param options options, may be null. 55 */ 56 private MapPatternConverter(final String[] options, String... format) { 57 super(options != null && options.length > 0 ? "MAP{" + options[0] + '}' : "MAP", "map"); 58 key = options != null && options.length > 0 ? options[0] : null; 59 this.format = format; 60 } 61 62 /** 63 * Obtains an instance of {@link MapPatternConverter}. 64 * 65 * @param options options, may be null or first element contains name of property to format. 66 * @return instance of {@link MapPatternConverter}. 67 */ 68 public static MapPatternConverter newInstance(final String[] options) { 69 return new MapPatternConverter(options, JAVA_UNQUOTED); 70 } 71 72 /** 73 * Obtain an instance of {@link MapPatternConverter}. 74 * 75 * @param options options, may be null or first element contains name of property to format. 76 * @param format the format to use if no options are given (i.e., options is null). Ignored if options is non-null. 77 * @return instance of {@link MapPatternConverter}. 78 * @since 2.11.2 79 */ 80 public static MapPatternConverter newInstance(final String[] options, final MapFormat format) { 81 return new MapPatternConverter(options, Objects.toString(format, JAVA_UNQUOTED)); 82 } 83 84 /** 85 * {@inheritDoc} 86 */ 87 @Override 88 public void format(final LogEvent event, final StringBuilder toAppendTo) { 89 MapMessage msg; 90 if (event.getMessage() instanceof MapMessage) { 91 msg = (MapMessage) event.getMessage(); 92 } else { 93 return; 94 } 95 // if there is no additional options, we output every single 96 // Key/Value pair for the Map in a similar format to Hashtable.toString() 97 if (key == null) { 98 msg.formatTo(format, toAppendTo); 99 } else { 100 // otherwise they just want a single key output 101 final String val = msg.get(key); 102 103 if (val != null) { 104 toAppendTo.append(val); 105 } 106 } 107 } 108 }