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.config.plugins;
018    
019    import java.lang.annotation.Documented;
020    import java.lang.annotation.ElementType;
021    import java.lang.annotation.Retention;
022    import java.lang.annotation.RetentionPolicy;
023    import java.lang.annotation.Target;
024    
025    import 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)
033    public @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        boolean printObject() default false;
058    
059        boolean deferChildren() default false;
060    }