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.config.plugins; 018 019import java.lang.annotation.Documented; 020import java.lang.annotation.ElementType; 021import java.lang.annotation.Retention; 022import java.lang.annotation.RetentionPolicy; 023import java.lang.annotation.Target; 024 025import org.apache.logging.log4j.util.Strings; 026 027/** 028 * Annotation that identifies a Class as a Plugin. 029 */ 030@Documented 031@Retention(RetentionPolicy.RUNTIME) 032@Target(ElementType.TYPE) 033public @interface Plugin { 034 035 /** 036 * Value of the elementType when none is specified. 037 */ 038 String EMPTY = Strings.EMPTY; 039 040 /** 041 * Name of the plugin. Note that this name is case-insensitive. 042 */ 043 String name(); 044 045 /** 046 * Category to place the plugin under. Category names are case-sensitive. 047 */ 048 String category(); 049 050 /** 051 * Name of the corresponding category of elements this plugin belongs under. For example, {@code appender} would 052 * indicate an {@link org.apache.logging.log4j.core.Appender} plugin which would be in the 053 * {@code <Appenders/>} element of a {@link org.apache.logging.log4j.core.config.Configuration}. 054 */ 055 String elementType() default EMPTY; 056 057 /** 058 * Indicates if the plugin class implements a useful {@link Object#toString()} method for use in log messages. 059 */ 060 boolean printObject() default false; 061 062 boolean deferChildren() default false; 063}