Spring Batch 3 - Job异常处理

上篇文章中，我们了解了读文件写数据库的流程。这里我们假设，日志文件在某一行的数据异常，比如逗号分隔后不是5部分，而变成了6部分，当程序执行到此行时就会抛出 FlatFileParseException 异常，Job停止执行。我们可以从两部分解决这个问题如果我们想让程序忽略这种异常，可以修改Job的配置方式如下：。

以下场景都是基于Spring Batch 3 - 读文件写数据库这篇文件。

忽略异常

有些情况下，我们想让程序忽略掉这种异常，修改Job配置如下：

skip-limit="2000" 指可以忽略的最大次数（行数），如果你不知道你有都少个异常数据，想全部忽略掉，就尽量配置的大点

Job重新执行

另外的情况，出错时让程序停止，通过手工或其它方式纠正错误后，让程序继续执行。当然，比如我们处理到2051行错误时，纠正错误数据后，我们希望Job能继续从上次失败的行继续开始处理，而不是从第1行从头再来。这就是Spring Batch的优势，它会自动记录你上次执行成功的地址，再次执行此job时会从这里继续出来。

我们来实际模拟下，假设我们在2051行的数据为：

2016-11-18 13:31:53,/test/user/user_visit/saveVisitStep,gz_qinrong,3,/test/3.201610171_1/Android,/5.1.1/Mi-4c/4faccbe5-bb26-4a0c-94aa-d9e0805f6367

注意在Android后面多加了一个逗号，导致此行逗号分隔后有6部分，而不是正常的5部分

执行job时我们会发生如下异常：

org.springframework.batch.item.file.FlatFileParseException: Parsing error at line: 2051 in resource=[URL [file:/my/access.log]], input=[2016-11-18 13:31:53,/test/user/user_visit/saveVisitStep,gz_qinrong,3,/test/3.201610171_1/Android,/5.1.1/Mi-4c/4faccbe5-bb26-4a0c-94aa-d9e0805f6367]
 at org.springframework.batch.item.file.FlatFileItemReader.doRead(FlatFileItemReader.java:183)
 at org.springframework.batch.item.support.AbstractItemCountingItemStreamItemReader.read(AbstractItemCountingItemStreamItemReader.java:88)
 at org.springframework.batch.core.step.item.SimpleChunkProvider.doRead(SimpleChunkProvider.java:91)
 at org.springframework.batch.core.step.item.SimpleChunkProvider.read(SimpleChunkProvider.java:157)
 at org.springframework.batch.core.step.item.SimpleChunkProvider$1.doInIteration(SimpleChunkProvider.java:116)
 at org.springframework.batch.repeat.support.RepeatTemplate.getNextResult(RepeatTemplate.java:374)
 at org.springframework.batch.repeat.support.RepeatTemplate.executeInternal(RepeatTemplate.java:215)
 at org.springframework.batch.repeat.support.RepeatTemplate.iterate(RepeatTemplate.java:144)
 at org.springframework.batch.core.step.item.SimpleChunkProvider.provide(SimpleChunkProvider.java:110)
 at org.springframework.batch.core.step.item.ChunkOrientedTasklet.execute(ChunkOrientedTasklet.java:69)
 at org.springframework.batch.core.step.tasklet.TaskletStep$ChunkTransactionCallback.doInTransaction(TaskletStep.java:406)
 at org.springframework.batch.core.step.tasklet.TaskletStep$ChunkTransactionCallback.doInTransaction(TaskletStep.java:330)
 at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:133)
 at org.springframework.batch.core.step.tasklet.TaskletStep$2.doInChunkContext(TaskletStep.java:271)
 at org.springframework.batch.core.scope.context.StepContextRepeatCallback.doInIteration(StepContextRepeatCallback.java:81)
 at org.springframework.batch.repeat.support.RepeatTemplate.getNextResult(RepeatTemplate.java:374)
 at org.springframework.batch.repeat.support.RepeatTemplate.executeInternal(RepeatTemplate.java:215)
 at org.springframework.batch.repeat.support.RepeatTemplate.iterate(RepeatTemplate.java:144)
 at org.springframework.batch.core.step.tasklet.TaskletStep.doExecute(TaskletStep.java:257)
 at org.springframework.batch.core.step.AbstractStep.execute(AbstractStep.java:200)
 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:169)
 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:306)
 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 com.me.springbatch.App.run(App.java:27)
 at com.me.springbatch.file2db.File2DBMain.main(File2DBMain.java:9)
Caused by: org.springframework.batch.item.file.transform.IncorrectTokenCountException: Incorrect number of tokens found in record: expected 5 actual 6
 at org.springframework.batch.item.file.transform.AbstractLineTokenizer.tokenize(AbstractLineTokenizer.java:125)
 at org.springframework.batch.item.file.mapping.DefaultLineMapper.mapLine(DefaultLineMapper.java:43)
 at org.springframework.batch.item.file.FlatFileItemReader.doRead(FlatFileItemReader.java:180)
 ... 31 more

Spring Batch 表BATCH_STEP_EXECUTION中的信息如下：