001/* 002 * Copyright 2006-2018 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 */ 016package org.springframework.batch.core.listener; 017 018import java.util.Iterator; 019import java.util.List; 020 021import org.springframework.batch.core.ItemProcessListener; 022import org.springframework.core.Ordered; 023import org.springframework.lang.Nullable; 024 025/** 026 * @author Dave Syer 027 * @author Mahmoud Ben Hassine 028 * 029 */ 030public class CompositeItemProcessListener<T, S> implements ItemProcessListener<T, S> { 031 032 private OrderedComposite<ItemProcessListener<? super T, ? super S>> listeners = new OrderedComposite<ItemProcessListener<? super T, ? super S>>(); 033 034 /** 035 * Public setter for the listeners. 036 * 037 * @param itemProcessorListeners list of {@link ItemProcessListener}s to be called when process events occur. 038 */ 039 public void setListeners(List<? extends ItemProcessListener<? super T, ? super S>> itemProcessorListeners) { 040 this.listeners.setItems(itemProcessorListeners); 041 } 042 043 /** 044 * Register additional listener. 045 * 046 * @param itemProcessorListener instance of {@link ItemProcessListener} to be registered. 047 */ 048 public void register(ItemProcessListener<? super T, ? super S> itemProcessorListener) { 049 listeners.add(itemProcessorListener); 050 } 051 052 /** 053 * Call the registered listeners in reverse order, respecting and 054 * prioritising those that implement {@link Ordered}. 055 * @see org.springframework.batch.core.ItemProcessListener#afterProcess(java.lang.Object, 056 * java.lang.Object) 057 */ 058 @Override 059 public void afterProcess(T item, @Nullable S result) { 060 for (Iterator<ItemProcessListener<? super T, ? super S>> iterator = listeners.reverse(); iterator.hasNext();) { 061 ItemProcessListener<? super T, ? super S> listener = iterator.next(); 062 listener.afterProcess(item, result); 063 } 064 } 065 066 /** 067 * Call the registered listeners in order, respecting and prioritising those 068 * that implement {@link Ordered}. 069 * @see org.springframework.batch.core.ItemProcessListener#beforeProcess(java.lang.Object) 070 */ 071 @Override 072 public void beforeProcess(T item) { 073 for (Iterator<ItemProcessListener<? super T, ? super S>> iterator = listeners.iterator(); iterator.hasNext();) { 074 ItemProcessListener<? super T, ? super S> listener = iterator.next(); 075 listener.beforeProcess(item); 076 } 077 } 078 079 /** 080 * Call the registered listeners in reverse order, respecting and 081 * prioritising those that implement {@link Ordered}. 082 * @see org.springframework.batch.core.ItemProcessListener#onProcessError(java.lang.Object, 083 * java.lang.Exception) 084 */ 085 @Override 086 public void onProcessError(T item, Exception e) { 087 for (Iterator<ItemProcessListener<? super T, ? super S>> iterator = listeners.reverse(); iterator.hasNext();) { 088 ItemProcessListener<? super T, ? super S> listener = iterator.next(); 089 listener.onProcessError(item, e); 090 } 091 } 092 093}