1 /* 2 * Copyright (c) 2004-2008 QOS.ch 3 * All rights reserved. 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining 6 * a copy of this software and associated documentation files (the 7 * "Software"), to deal in the Software without restriction, including 8 * without limitation the rights to use, copy, modify, merge, publish, 9 * distribute, sublicense, and/or sell copies of the Software, and to 10 * permit persons to whom the Software is furnished to do so, subject to 11 * the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be 14 * included in all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 17 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 19 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 20 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 21 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 22 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 23 */ 24 25 package org.slf4j; 26 27 import java.io.Serializable; 28 import java.util.Iterator; 29 30 /** 31 * Markers are named objects used to enrich log statements. Conforming logging 32 * system Implementations of SLF4J determine how information conveyed by markers 33 * are used, if at all. In particular, many conforming logging systems ignore 34 * marker data. 35 * 36 * <p> 37 * Markers can contain child markers, which in turn can contain children of 38 * their own. 39 * 40 * @author Ceki Gülcü 41 */ 42 public interface Marker extends Serializable { 43 44 /** 45 * This constant represents any marker, including a null marker. 46 */ 47 public final String ANY_MARKER = "*"; 48 49 /** 50 * This constant represents any non-null marker. 51 */ 52 public final String ANY_NON_NULL_MARKER = "+"; 53 54 /** 55 * Get the name of this Marker. 56 * 57 * @return name of marker 58 */ 59 public String getName(); 60 61 /** 62 * Add a child Marker to this Marker. 63 * 64 * @param child 65 * a child marker 66 */ 67 public void add(Marker child); 68 69 /** 70 * Remove a child Marker. 71 * 72 * @param child 73 * the child Marker to remove 74 * @return true if child could be found and removed, false otherwise. 75 */ 76 public boolean remove(Marker child); 77 78 /** 79 * Does this marker have children? 80 * 81 * @return true if this marker has children, false otherwise. 82 */ 83 public boolean hasChildren(); 84 85 /** 86 * Returns an Iterator which can be used to iterate over the children of this 87 * marker. An empty iterator is returned when this marker has no children. 88 * 89 * @return Iterator over the children of this marker 90 */ 91 public Iterator iterator(); 92 93 /** 94 * Does this marker contain the 'other' marker? Marker A is defined to contain 95 * marker B, if A == B or if B is a child of A. 96 * 97 * @param other 98 * The marker to test for inclusion. 99 * @throws IllegalArgumentException 100 * if 'other' is null 101 * @return Whether this marker contains the other marker. 102 */ 103 public boolean contains(Marker other); 104 105 /** 106 * Does this marker contain the marker named 'name'? 107 * 108 * If 'name' is null the returned value is always false. 109 * 110 * @param other 111 * The marker to test for inclusion. 112 * @return Whether this marker contains the other marker. 113 */ 114 public boolean contains(String name); 115 116 /** 117 * Markers are considered equal if they have the same name. 118 * 119 * @param o 120 * @return true, if this.name equals o.name 121 * 122 * @since 1.5.1 123 */ 124 public boolean equals(Object o); 125 126 /** 127 * Compute the hash code based on the name of this marker. 128 * Note that markers are considered equal if they have the same name. 129 * 130 * @return the computed hashCode 131 * @since 1.5.1 132 */ 133 public int hashCode(); 134 135 }