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.amqp.builder; 018 019import org.springframework.amqp.core.AmqpTemplate; 020import org.springframework.batch.item.amqp.AmqpItemReader; 021import org.springframework.util.Assert; 022 023/** 024 * A builder implementation for the {@link AmqpItemReader} 025 * 026 * @author Glenn Renfro 027 * @since 4.0 028 * @see AmqpItemReader 029 */ 030public class AmqpItemReaderBuilder<T> { 031 032 private AmqpTemplate amqpTemplate; 033 034 private Class<? extends T> itemType; 035 036 /** 037 * Establish the amqpTemplate to be used by the AmqpItemReader. 038 * @param amqpTemplate the template to be used. 039 * @return this instance for method chaining 040 * @see AmqpItemReader#AmqpItemReader(AmqpTemplate) 041 */ 042 public AmqpItemReaderBuilder<T> amqpTemplate(AmqpTemplate amqpTemplate) { 043 this.amqpTemplate = amqpTemplate; 044 045 return this; 046 } 047 048 /** 049 * Establish the itemType for the reader. 050 * @param itemType class type that will be returned by the reader. 051 * @return this instance for method chaining. 052 * @see AmqpItemReader#setItemType(Class) 053 */ 054 public AmqpItemReaderBuilder<T> itemType(Class<? extends T> itemType) { 055 this.itemType = itemType; 056 057 return this; 058 } 059 060 /** 061 * Validates and builds a {@link AmqpItemReader}. 062 * 063 * @return a {@link AmqpItemReader} 064 */ 065 public AmqpItemReader<T> build() { 066 Assert.notNull(this.amqpTemplate, "amqpTemplate is required."); 067 068 AmqpItemReader<T> reader = new AmqpItemReader<>(this.amqpTemplate); 069 if(this.itemType != null) { 070 reader.setItemType(this.itemType); 071 } 072 073 return reader; 074 } 075}