Added AmqpItemWriterBuilder

resolves BATCH-2626

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/amqp/builder/AmqpItemWriterBuilder.java

@@ -0,0 +1,58 @@
+/*
+ * 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.amqp.builder;
+
+import org.springframework.amqp.core.AmqpTemplate;
+import org.springframework.batch.item.amqp.AmqpItemWriter;
+import org.springframework.util.Assert;
+
+/**
+ * A builder implementation for the {@link AmqpItemWriter}
+ * @author Glenn Renfro
+ * @since 4.0
+ * @see AmqpItemWriter
+ */
+public class AmqpItemWriterBuilder<T> {
+
+	private AmqpTemplate amqpTemplate;
+
+	/**
+	 * Establish the amqpTemplate to be used by the AmqpItemWriter.
+	 * @param amqpTemplate the template to be used.
+	 * @return this instance for method chaining
+	 * @see AmqpItemWriter#AmqpItemWriter(AmqpTemplate)
+	 */
+	public AmqpItemWriterBuilder<T> amqpTemplate(AmqpTemplate amqpTemplate) {
+		this.amqpTemplate = amqpTemplate;
+
+		return this;
+	}
+
+	/**
+	 * Validates and builds a {@link AmqpItemWriter}.
+	 *
+	 * @return a {@link AmqpItemWriter}
+	 */
+	public AmqpItemWriter<T> build() {
+		Assert.notNull(this.amqpTemplate, "amqpTemplate is required.");
+
+		AmqpItemWriter<T> writer = new AmqpItemWriter<>(this.amqpTemplate);
+
+		return writer;
+	}
+
+}

spring-batch-infrastructure/src/test/java/org/springframework/batch/item/amqp/builder/AmqpItemWriterBuilderTests.java

@@ -0,0 +1,59 @@
+/*
+ * 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.amqp.builder;
+
+import java.util.Arrays;
+
+import org.junit.Test;
+
+import org.springframework.amqp.core.AmqpTemplate;
+import org.springframework.amqp.core.Message;
+import org.springframework.batch.item.amqp.AmqpItemWriter;
+
+import static org.aspectj.bridge.MessageUtil.fail;
+import static org.junit.Assert.assertEquals;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+
+/**
+ * @author Glenn Renfro
+ */
+public class AmqpItemWriterBuilderTests {
+
+	@Test
+	public void testNullAmqpTemplate() {
+		try {
+			new AmqpItemWriterBuilder<Message>().build();
+			fail("IllegalArgumentException should have been thrown");
+		}
+		catch (IllegalArgumentException iae) {
+			assertEquals("IllegalArgumentException message did not match the expected result.",
+					"amqpTemplate is required.", iae.getMessage());
+		}
+	}
+
+	@Test
+	public void voidTestWrite() throws Exception {
+		AmqpTemplate amqpTemplate = mock(AmqpTemplate.class);
+
+		AmqpItemWriter<String> amqpItemWriter =
+				new AmqpItemWriterBuilder<String>().amqpTemplate(amqpTemplate).build();
+		amqpItemWriter.write(Arrays.asList("foo", "bar"));
+		verify(amqpTemplate).convertAndSend("foo");
+		verify(amqpTemplate).convertAndSend("bar");
+	}
+}