Added CompositeItemWriterBuilder.

resolves BATCH-2597

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/support/CompositeItemWriter.java

@@ -41,6 +41,14 @@ public class CompositeItemWriter<T> implements ItemStreamWriter<T>, Initializing
 
 	private boolean ignoreItemStream = false;
 
+	/**
+	 * Establishes the policy whether to call the open, close, or update methods for the
+	 * item writer delegates associated with the CompositeItemWriter.
+	 * 
+	 * @param ignoreItemStream if false the delegates' open, close, or update methods will
+	 * be called when the corresponding methods on the CompositeItemWriter are called. If
+	 * true the delegates' open, close, nor update methods will not be called (default is false).
+	 */
 	public void setIgnoreItemStream(boolean ignoreItemStream) {
 		this.ignoreItemStream = ignoreItemStream;
 	}
@@ -58,6 +66,12 @@ public class CompositeItemWriter<T> implements ItemStreamWriter<T>, Initializing
 		Assert.notEmpty(delegates, "The 'delegates' may not be empty");
 	}
 
+	/**
+	 * The list of item writers to use as delegates. Items are written to each of the
+	 * delegates.
+	 *
+	 * @param delegates the list of delegates to use.  The delegates list must not be null nor be empty.
+	 */
 	public void setDelegates(List<ItemWriter<? super T>> delegates) {
 		this.delegates = delegates;
 	}

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/support/builder/CompositeItemWriterBuilder.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright 2017 the original author or authors.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *          http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package org.springframework.batch.item.support.builder;
+
+import java.util.List;
+
+import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.support.CompositeItemWriter;
+import org.springframework.util.Assert;
+
+/**
+ * Creates a fully qualified CompositeItemWriter.
+ *
+ * @author Glenn Renfro
+ *
+ * @since 4.0
+ */
+public class CompositeItemWriterBuilder<T> {
+	private List<ItemWriter<? super T>> delegates;
+
+	private boolean ignoreItemStream = false;
+
+	/**
+	 * Establishes the policy whether to call the open, close, or update methods for the
+	 * item writer delegates associated with the CompositeItemWriter.
+	 *
+	 * @param ignoreItemStream if false the delegates' open, close, or update methods will
+	 * be called when the corresponding methods on the CompositeItemWriter are called. If
+	 * true the delegates' open, close, nor update methods will not be called (default is false).
+	 * @return this instance for method chaining.
+	 * 
+	 * @see CompositeItemWriter#setIgnoreItemStream(boolean)
+	 */
+	public CompositeItemWriterBuilder<T> ignoreItemStream(boolean ignoreItemStream) {
+		this.ignoreItemStream = ignoreItemStream;
+
+		return this;
+	}
+
+	/**
+	 * The list of item writers to use as delegates. Items are written to each of the
+	 * delegates.
+	 *
+	 * @param delegates the list of delegates to use. The delegates list must not be null
+	 * nor be empty.
+	 * @return this instance for method chaining.
+	 * 
+	 * @see CompositeItemWriter#setDelegates(List)
+	 */
+	public CompositeItemWriterBuilder<T> delegates(List<ItemWriter<? super T>> delegates) {
+		this.delegates = delegates;
+
+		return this;
+	}
+
+	/**
+	 * Returns a fully constructed {@link CompositeItemWriter}.
+	 *
+	 * @return a new {@link CompositeItemWriter}
+	 */
+	public CompositeItemWriter<T> build() {
+		Assert.notNull(delegates, "A list of delegates is required.");
+		Assert.notEmpty(delegates, "The delegates list must have one or more delegates.");
+
+		CompositeItemWriter<T> writer = new CompositeItemWriter<>();
+		writer.setDelegates(this.delegates);
+		writer.setIgnoreItemStream(this.ignoreItemStream);
+		return writer;
+	}
+}