SkipListener在chunk处理阶段抛出跳过定义的异常时触发,在chunk的读、处理、写阶段发生的异常都会触发该拦截器
SkipListener接口声明:
/* * Copyright 2006-2007 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.core; /** * Interface for listener to skipped items. Callbacks will be called by * {@link Step} implementations at the appropriate time in the step lifecycle. * Implementers of this interface should not assume that any method will be * called immediately after an error has been encountered. Because there * may be errors later on in processing the chunk, this listener will not be * called until just before committing. * * @author Dave Syer * @author Robert Kasanicky * */ public interface SkipListener<T,S> extends StepListener { /** * Callback for a failure on read that is legal, so is not going to be * re-thrown. In case transaction is rolled back and items are re-read, this * callback will occur repeatedly for the same cause. This will only happen * if read items are not buffered. * * @param t cause of the failure */ void onSkipInRead(Throwable t); /** * This item failed on write with the given exception, and a skip was called * for. * * @param item the failed item * @param t the cause of the failure */ void onSkipInWrite(S item, Throwable t); /** * This item failed on processing with the given exception, and a skip was called * for. * * @param item the failed item * @param t the cause of the failure */ void onSkipInProcess(T item, Throwable t); }SkipListener方法说明及注解定义
方法 | 方法说明 | 注解定义 |
onSkipInRead(Throwable t) | 在读阶段发生异常并且配置了异常可以跳过时触发该操作 | @OnSkipInRead |
onSkipInWrite(String item, Throwable t) | 在写阶段发生异常并且配置了异常可以跳过时触发该操作 | @OnSkipInWrite |
onSkipInProcess(String item, Throwable t) | 在处理阶段发生异常并且配置了异常可以跳过时触发该操作 | @OnSkipInProcess |
CompositeSkipListener ---组合跳过拦截器
MulticasterBatchListener--组合策略跳过拦截器
SkipListenerSupport----跳过拦截器默认实现
自定义SkipListener实现示例:
/** * */ package com.juxtapose.example.ch05.step.listener; import org.springframework.batch.core.SkipListener; import org.springframework.batch.core.annotation.OnSkipInProcess; import org.springframework.batch.item.file.FlatFileParseException; import org.springframework.jdbc.core.JdbcTemplate; /** * 自定义SkipListener * @author wbw * */ public class DBSkipListener implements SkipListener<String, String> { private JdbcTemplate jdbcTemplate; @OnSkipInProcess public void onSkipInRead(Throwable t) { if (t instanceof FlatFileParseException) { jdbcTemplate.update("insert into skipbills " + "(line,content) values (?,?)", ((FlatFileParseException) t).getLineNumber(), ((FlatFileParseException) t).getInput()); } } public void onSkipInWrite(String item, Throwable t) { } public void onSkipInProcess(String item, Throwable t) { } public JdbcTemplate getJdbcTemplate() { return jdbcTemplate; } public void setJdbcTemplate(JdbcTemplate jdbcTemplate) { this.jdbcTemplate = jdbcTemplate; } }