捕获异常时抑制堆栈跟踪答案

【问题标题】：Suppressing stack trace when catching exception捕获异常时抑制堆栈跟踪
【发布时间】：2015-07-01 17:47:43
【问题描述】：

我有一个简短的 2 步 Spring Batch 作业，它在严格模式下使用 StaxEventItemReader 从 xml 休息服务调用中读取。我希望它处于严格模式，因为无法连接到其余服务，因此没有理由继续。我想捕获异常并使用自定义消息优雅地退出，而不是使用堆栈跟踪。

我可以使用 StepExecutionListener 和 afterStep() 方法来检查异常 (stepExecution.getFailureExceptions())，但仍在输出堆栈跟踪。我收到了我的自定义消息（下面的 STS 输出中的 13:05:32,981）以及堆栈跟踪。当我将 ItemReaderListener 与 onError 方法一起使用时，未调用 onError 方法，我猜是因为它是初始化异常而不是读取错误。

捕获无法初始化读取器异常并抑制输出中的堆栈跟踪的最佳方法是什么？

SpringBatch 作业：

	<batch:job id="randomSends2NG">
		<batch:step id="getStations" next="generateAndSend">
			<batch:tasklet>
				<batch:chunk reader="getStationsFromNG_RestXML" 
							 processor="idExtractor"
							 writer="stationsWriter"
							 commit-interval="1">
				</batch:chunk>	
				<batch:listeners>
					<batch:listener ref="noStationsStopListener" />
				</batch:listeners>		
				
			</batch:tasklet>
		</batch:step>
		<batch:step id="generateAndSend">
			<batch:tasklet>
				<batch:chunk reader="readStationIdsList" 
							 processor="createRandomRequests"
							 writer="ngBroadcasterService"
							 commit-interval="400">
				</batch:chunk>			
			</batch:tasklet>
		</batch:step>
	</batch:job>

带有堆栈跟踪的 STS 输出：

13:05:30,479 [main] INFO  SimpleJobLauncher  - No TaskExecutor has been set, defaulting to synchronous executor.
13:05:30,776 [main] INFO  DepartmentSendCountsNoOpReader  - constructing stationSendCountsReader
LightYellow color:43
13:05:31,368 [main] INFO  ProcessStatisticsTasklet  - constructor...
13:05:31,525 [main] INFO  RequestsListReader  - constructing requestsListReader
13:05:31,588 [main] INFO  Jaxb2Marshaller  - Creating JAXBContext with classes to be bound [class com.pevco.pevcotubesystem.StationConfig]
13:05:31,886 [main] INFO  SimpleJobLauncher  - Job: [FlowJob: [name=randomSends2NG]] launched with the following parameters: [{hostNameOrIP=192.168.100.10:8383}]
13:05:31,902 [main] INFO  SimpleStepHandler  - Executing step: [getStations]
13:05:32,981 [main] ERROR AbstractStep  - Encountered an error executing step getStations in job randomSends2NG
org.springframework.batch.item.ItemStreamException: Failed to initialize the reader
	at org.springframework.batch.item.support.AbstractItemCountingItemStreamItemReader.open(AbstractItemCountingItemStreamItemReader.java:147)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:497)
	at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:307)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
	at org.springframework.aop.support.DelegatingIntroductionInterceptor.doProceed(DelegatingIntroductionInterceptor.java:131)
	at org.springframework.aop.support.DelegatingIntroductionInterceptor.invoke(DelegatingIntroductionInterceptor.java:119)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
	at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
	at com.sun.proxy.$Proxy8.open(Unknown Source)
	at org.springframework.batch.item.support.CompositeItemStream.open(CompositeItemStream.java:96)
	at org.springframework.batch.core.step.tasklet.TaskletStep.open(TaskletStep.java:310)
	at org.springframework.batch.core.step.AbstractStep.execute(AbstractStep.java:195)
	at org.springframework.batch.core.job.SimpleStepHandler.handleStep(SimpleStepHandler.java:148)
	at org.springframework.batch.core.job.flow.JobFlowExecutor.executeStep(JobFlowExecutor.java:64)
	at org.springframework.batch.core.job.flow.support.state.StepState.handle(StepState.java:67)
	at org.springframework.batch.core.job.flow.support.SimpleFlow.resume(SimpleFlow.java:165)
	at org.springframework.batch.core.job.flow.support.SimpleFlow.start(SimpleFlow.java:144)
	at org.springframework.batch.core.job.flow.FlowJob.doExecute(FlowJob.java:134)
	at org.springframework.batch.core.job.AbstractJob.execute(AbstractJob.java:304)
	at org.springframework.batch.core.launch.support.SimpleJobLauncher$1.run(SimpleJobLauncher.java:135)
	at org.springframework.core.task.SyncTaskExecutor.execute(SyncTaskExecutor.java:50)
	at org.springframework.batch.core.launch.support.SimpleJobLauncher.run(SimpleJobLauncher.java:128)
	at org.springframework.batch.core.launch.support.CommandLineJobRunner.start(CommandLineJobRunner.java:362)
	at org.springframework.batch.core.launch.support.CommandLineJobRunner.main(CommandLineJobRunner.java:590)
Caused by: java.lang.IllegalStateException: Input resource must exist (reader is in 'strict' mode)
	at org.springframework.batch.item.xml.StaxEventItemReader.doOpen(StaxEventItemReader.java:195)
	at org.springframework.batch.item.support.AbstractItemCountingItemStreamItemReader.open(AbstractItemCountingItemStreamItemReader.java:144)
	... 27 more
13:05:32,981 [main] ERROR NoStationsStopListener  - Not able to get stations list from NG. Check that NG is running
13:05:32,998 [main] INFO  SimpleJobLauncher  - Job: [FlowJob: [name=randomSends2NG]] completed with the following parameters: [{hostNameOrIP=192.168.100.10:8383}] and the following status: [FAILED]
13:05:32,998 [main] INFO  ClassPathXmlApplicationContext  - Closing org.springframework.context.support.ClassPathXmlApplicationContext@4f4a7090: startup date [Wed Jul 01 13:05:29 EDT 2015]; root of context hierarchy

【问题讨论】：

标签： exception-handling spring-batch

【解决方案1】：

当面临这个问题时，最好的解决方案可能是尽快检查 REST 服务，因为 “没有连接到 REST 服务的能力，没有理由继续 [...] 并优雅退出带有自定义消息”。
在第一步之前使用JobExecutionDecider，您可以在其中检查 REST 可用性并根据服务存在/不存在继续或结束您的工作。

【讨论】：