001/**
002 * Copyright (C) 2006-2026 Talend Inc. - www.talend.com
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.talend.sdk.component.api.processor;
017
018import static java.lang.annotation.ElementType.PARAMETER;
019import static java.lang.annotation.RetentionPolicy.RUNTIME;
020
021import java.lang.annotation.Retention;
022import java.lang.annotation.Target;
023
024@Target(PARAMETER)
025@Retention(RUNTIME)
026public @interface Output {
027
028    /**
029     * The output branch fed by this parameter.
030     *
031     * Used by {@link OutputEmitter} parameters, which always feed exactly one branch, and by
032     * {@link MultiOutputIterator} parameters streaming to a single branch.
033     *
034     * @return the branch name, {@code __default__} if not set.
035     */
036    String value() default "__default__";
037
038    /**
039     * The branches a {@link MultiOutputIterator} parameter routes records to, when it feeds more than one.
040     *
041     * This is declarative metadata only: it lets the design/Studio layer know the output connections
042     * of the component, the routing itself is done at runtime through {@link TaggedOutput} or
043     * {@link MultiOutputIterator#setIterator(String, java.util.Iterator)}.
044     * When left empty, {@link #value()} is used, which covers the single branch streaming case.
045     * It is not supported on {@link OutputEmitter} parameters.
046     *
047     * @return the branch names, empty to fallback on {@link #value()}.
048     */
049    String[] branches() default {};
050}