I'm using Spring Batch 4.3.8 and I'm trying to use the following code in my configuration to define a ItemWriter
@Bean
@StepScope
public ItemWriter<MyData> itemWriter(MyFileConfig fileConfig) {
String outputFileName = fileConfig.retrieveOutputFileName();
if (StringUtils.isBlank(outputFileName)) {
return new MyOtherWriter<>();
}
return new FlatFileItemWriterBuilder<MyData>().name(WRITER_NAME)
.resource(new FileSystemResource(outputFileName))
.delimited()
.delimiter(DELIMITER)
.names(NAMES)
.build();
}
but I'm getting the following error when outputFileName is not blank
org.springframework.batch.item.WriterNotOpenException: Writer must be open before it can be written to
at org.springframework.batch.item.support.AbstractFileItemWriter.write(AbstractFileItemWriter.java:239)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:344)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:198)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
at org.springframework.aop.support.DelegatingIntroductionInterceptor.doProceed(DelegatingIntroductionInterceptor.java:137)
at org.springframework.aop.support.DelegatingIntroductionInterceptor.invoke(DelegatingIntroductionInterceptor.java:124)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:241)
at com.sun.proxy.$Proxy124.write(Unknown Source)
at org.springframework.batch.core.step.item.SimpleChunkProcessor.writeItems(SimpleChunkProcessor.java:193)
at org.springframework.batch.core.step.item.SimpleChunkProcessor.doWrite(SimpleChunkProcessor.java:159)
at org.springframework.batch.core.step.item.SimpleChunkProcessor.write(SimpleChunkProcessor.java:294)
at org.springframework.batch.core.step.item.SimpleChunkProcessor.process(SimpleChunkProcessor.java:217)
at org.springframework.batch.core.step.item.ChunkOrientedTasklet.execute(ChunkOrientedTasklet.java:77)
at org.springframework.batch.core.step.tasklet.TaskletStep$ChunkTransactionCallback.doInTransaction(TaskletStep.java:407)
at org.springframework.batch.core.step.tasklet.TaskletStep$ChunkTransactionCallback.doInTransaction(TaskletStep.java:331)
at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:140)
at org.springframework.batch.core.step.tasklet.TaskletStep$2.doInChunkContext(TaskletStep.java:273)
at org.springframework.batch.core.scope.context.StepContextRepeatCallback.doInIteration(StepContextRepeatCallback.java:82)
at org.springframework.batch.repeat.support.RepeatTemplate.getNextResult(RepeatTemplate.java:375)
at org.springframework.batch.repeat.support.RepeatTemplate.executeInternal(RepeatTemplate.java:215)
at org.springframework.batch.repeat.support.RepeatTemplate.iterate(RepeatTemplate.java:145)
at org.springframework.batch.core.step.tasklet.TaskletStep.doExecute(TaskletStep.java:258)
at org.springframework.batch.core.step.AbstractStep.execute(AbstractStep.java:208)
at org.springframework.batch.core.job.SimpleStepHandler.handleStep(SimpleStepHandler.java:152)
at org.springframework.batch.core.job.AbstractJob.handleStep(AbstractJob.java:413)
at org.springframework.batch.core.job.SimpleJob.doExecute(SimpleJob.java:136)
at org.springframework.batch.core.job.AbstractJob.execute(AbstractJob.java:320)
at org.springframework.batch.core.launch.support.SimpleJobLauncher$1.run(SimpleJobLauncher.java:149)
at org.springframework.core.task.SyncTaskExecutor.execute(SyncTaskExecutor.java:50)
at org.springframework.batch.core.launch.support.SimpleJobLauncher.run(SimpleJobLauncher.java:140)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:344)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:198)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
at org.springframework.batch.core.configuration.annotation.SimpleBatchConfiguration$PassthruAdvice.invoke(SimpleBatchConfiguration.java:128)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:241)
at com.sun.proxy.$Proxy120.run(Unknown Source)
at org.springframework.boot.autoconfigure.batch.JobLauncherApplicationRunner.execute(JobLauncherApplicationRunner.java:199)
at org.springframework.boot.autoconfigure.batch.JobLauncherApplicationRunner.executeLocalJobs(JobLauncherApplicationRunner.java:173)
at org.springframework.boot.autoconfigure.batch.JobLauncherApplicationRunner.launchJobFromProperties(JobLauncherApplicationRunner.java:160)
at org.springframework.boot.autoconfigure.batch.JobLauncherApplicationRunner.run(JobLauncherApplicationRunner.java:155)
at org.springframework.boot.autoconfigure.batch.JobLauncherApplicationRunner.run(JobLauncherApplicationRunner.java:150)
at org.springframework.cloud.sleuth.instrument.task.TraceApplicationRunner.run(TraceApplicationRunner.java:51)
at org.springframework.boot.SpringApplication.callRunner(SpringApplication.java:759)
at org.springframework.boot.SpringApplication.callRunners(SpringApplication.java:749)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:314)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1303)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1292)
Yet this code is working fine
@Bean
@StepScope
public FlatFileItemWriter<MyData> itemWriter(MyFileConfig fileConfig) {
return new FlatFileItemWriterBuilder<MyData>().name(WRITER_NAME)
.resource(new FileSystemResource(fileConfig.retrieveOutputFileName()))
.delimited()
.delimiter(DELIMITER)
.names(NAMES)
.build();
}
so I'm assuming the issue is that Spring Batch is not checking that the ItemWriter is actually a FlatFileItemWriter and doing the proper init. Is there a way to comfortably handle this case, without duplicating config (the various @Conditional annotations on beans)?
When using the Java configuration style to define step scoped ItemStream beans, the return type of the bean definition method should be at least ItemStream. This is required so that Spring Batch correctly creates a proxy that implements this interface, and therefore honors its contract by calling open, update and close methods as expected.
This is mentioned in the documentation here: Scoping ItemStream components