    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    }