001/*
002 * Copyright 2017 the original author or authors.
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 *          https://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 */
016
017package org.springframework.batch.item.support.builder;
018
019import java.util.List;
020
021import org.springframework.batch.item.ItemWriter;
022import org.springframework.batch.item.support.CompositeItemWriter;
023import org.springframework.util.Assert;
024
025/**
026 * Creates a fully qualified CompositeItemWriter.
027 *
028 * @author Glenn Renfro
029 *
030 * @since 4.0
031 */
032public class CompositeItemWriterBuilder<T> {
033        private List<ItemWriter<? super T>> delegates;
034
035        private boolean ignoreItemStream = false;
036
037        /**
038         * Establishes the policy whether to call the open, close, or update methods for the
039         * item writer delegates associated with the CompositeItemWriter.
040         *
041         * @param ignoreItemStream if false the delegates' open, close, or update methods will
042         * be called when the corresponding methods on the CompositeItemWriter are called. If
043         * true the delegates' open, close, nor update methods will not be called (default is false).
044         * @return this instance for method chaining.
045         * 
046         * @see CompositeItemWriter#setIgnoreItemStream(boolean)
047         */
048        public CompositeItemWriterBuilder<T> ignoreItemStream(boolean ignoreItemStream) {
049                this.ignoreItemStream = ignoreItemStream;
050
051                return this;
052        }
053
054        /**
055         * The list of item writers to use as delegates. Items are written to each of the
056         * delegates.
057         *
058         * @param delegates the list of delegates to use. The delegates list must not be null
059         * nor be empty.
060         * @return this instance for method chaining.
061         * 
062         * @see CompositeItemWriter#setDelegates(List)
063         */
064        public CompositeItemWriterBuilder<T> delegates(List<ItemWriter<? super T>> delegates) {
065                this.delegates = delegates;
066
067                return this;
068        }
069
070        /**
071         * Returns a fully constructed {@link CompositeItemWriter}.
072         *
073         * @return a new {@link CompositeItemWriter}
074         */
075        public CompositeItemWriter<T> build() {
076                Assert.notNull(delegates, "A list of delegates is required.");
077                Assert.notEmpty(delegates, "The delegates list must have one or more delegates.");
078
079                CompositeItemWriter<T> writer = new CompositeItemWriter<>();
080                writer.setDelegates(this.delegates);
081                writer.setIgnoreItemStream(this.ignoreItemStream);
082                return writer;
083        }
084}