Spring Batch：在处理器中获取分区步骤的步骤上下文

Question

我正在开发一个Spring批处理作业，它使用MultiResourcePartitioner并行处理多个输入文件。在ItemProcessor中，我需要获取当前输入文件中的记录数。我从步骤上下文中获取当前文件名，并读取文件中的行数：

StepSynchronizationManager.register(stepExecution);
StepContext stepContext = StepSynchronizationManager.getContext();
StepSynchronizationManager.close();
log.trace("stepContext: " + stepContext.getStepExecution().getExecutionContext().entrySet().toString());
...
UrlResource currentFile = new UrlResource(stepContext.getStepExecution().getExecutionContext().getString("fileName"));

这一切似乎工作，但我得到例外时，从处理器线程访问步骤上下文：

2013-05-15 11:44:35,178 DEBUG [org.springframework.batch.core.step.tasklet.TaskletStep] <taskExecutor-3> - Rollback for RuntimeException: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'scopedTarget.processor': Scope 'step' is not active for the current thread; consider defining a scoped proxy for this bean if you intend to refer to it from a singleton; nested exception is java.lang.IllegalStateException: No context holder available for step scope
2013-05-15 11:44:35,194 DEBUG [org.springframework.jdbc.datasource.DataSourceUtils] <taskExecutor-3> - Returning JDBC Connection to DataSource
2013-05-15 11:44:35,194 DEBUG [org.springframework.batch.repeat.support.RepeatTemplate] <taskExecutor-3> - Handling exception: org.springframework.beans.factory.BeanCreationException, caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'scopedTarget.processor': Scope 'step' is not active for the current thread; consider defining a scoped proxy for this bean if you intend to refer to it from a singleton; nested exception is java.lang.IllegalStateException: No context holder available for step scope
2013-05-15 11:44:35,194 DEBUG [org.springframework.batch.repeat.support.RepeatTemplate] <taskExecutor-3> - Handling fatal exception explicitly (rethrowing first of 1): org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'scopedTarget.processor': Scope 'step' is not active for the current thread; consider defining a scoped proxy for this bean if you intend to refer to it from a singleton; nested exception is java.lang.IllegalStateException: No context holder available for step scope
2013-05-15 11:44:35,210 ERROR [org.springframework.batch.core.step.AbstractStep] <taskExecutor-3> - Encountered an error executing the step
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'scopedTarget.processor': Scope 'step' is not active for the current thread; consider defining a scoped proxy for this bean if you intend to refer to it from a singleton; nested exception is java.lang.IllegalStateException: No context holder available for step scope
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:341)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:192)
    at org.springframework.aop.target.SimpleBeanTargetSource.getTarget(SimpleBeanTargetSource.java:33)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:182)
    at $Proxy14.process(Unknown Source)
    at org.springframework.batch.core.step.item.SimpleChunkProcessor.doProcess(SimpleChunkProcessor.java:125)
    at org.springframework.batch.core.step.item.SimpleChunkProcessor.transform(SimpleChunkProcessor.java:291)
    at org.springframework.batch.core.step.item.SimpleChunkProcessor.process(SimpleChunkProcessor.java:190)
    at org.springframework.batch.core.step.item.ChunkOrientedTasklet.execute(ChunkOrientedTasklet.java:74)
    at org.springframework.batch.core.step.tasklet.TaskletStep$ChunkTransactionCallback.doInTransaction(TaskletStep.java:386)
    at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:130)
    at org.springframework.batch.core.step.tasklet.TaskletStep$2.doInChunkContext(TaskletStep.java:264)
    at org.springframework.batch.core.scope.context.StepContextRepeatCallback.doInIteration(StepContextRepeatCallback.java:76)
    at org.springframework.batch.repeat.support.RepeatTemplate.getNextResult(RepeatTemplate.java:367)
    at org.springframework.batch.repeat.support.RepeatTemplate.executeInternal(RepeatTemplate.java:214)
    at org.springframework.batch.repeat.support.RepeatTemplate.iterate(RepeatTemplate.java:143)
    at org.springframework.batch.core.step.tasklet.TaskletStep.doExecute(TaskletStep.java:250)
    at org.springframework.batch.core.step.AbstractStep.execute(AbstractStep.java:195)
    at org.springframework.batch.core.partition.support.TaskExecutorPartitionHandler$1.call(TaskExecutorPartitionHandler.java:120)
    at org.springframework.batch.core.partition.support.TaskExecutorPartitionHandler$1.call(TaskExecutorPartitionHandler.java:118)
    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
    at java.util.concurrent.FutureTask.run(FutureTask.java:166)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
    at java.lang.Thread.run(Thread.java:722)
Caused by: java.lang.IllegalStateException: No context holder available for step scope
    at org.springframework.batch.core.scope.StepScope.getContext(StepScope.java:197)
    at org.springframework.batch.core.scope.StepScope.get(StepScope.java:139)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:327)
    ... 24 more

有没有办法从分区作业的处理器获取当前输入文件名？

下面是相关配置：

<batch:job id="acct">
    <batch:step id="init" parent="abstractStep" next="processStep">
        <batch:tasklet ref="fileDeleteTasklet" />
    </batch:step>
    <batch:step id="processStep">
        <batch:partition step="processInput" partitioner="partitioner">
            <batch:handler grid-size="2" task-executor="taskExecutor" />
        </batch:partition>
    </batch:step>
</batch:job>

<batch:step id="processInput">
    <batch:tasklet>
        <batch:chunk reader="reader" processor="processor" writer="writer" commit-interval="3">
            <batch:streams>
                <batch:stream ref="reader"/>
                <batch:stream ref="flatFileItemWriter"/>
            </batch:streams>
        </batch:chunk>
    </batch:tasklet>
</batch:step>

<bean id="partitioner" class="org.springframework.batch.core.partition.support.MultiResourcePartitioner" scope="step">
    <property name="keyName" value="fileName"/>
    <property name="resources" value="file:#{jobParameters['inputFilePattern']}"/>
</bean>

<bean id="taskExecutor" class="org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor">
    <property name="corePoolSize" value="5"/>
    <property name="maxPoolSize" value="5"/>
</bean>

<bean id="reader" class="org.springframework.batch.item.file.FlatFileItemReader" scope="step">
    <property name="resource" value="#{stepExecutionContext[fileName]}" /> 
    <property name="lineMapper">
        <bean class="org.springframework.batch.item.file.mapping.DefaultLineMapper">
            <property name="lineTokenizer">
                <bean class="org.springframework.batch.item.file.transform.FixedLengthTokenizer">
                    <property name="names" value="recordType,reserved,aCode,bCode,acctNumber,idType,cCode" />
                    <property name="columns" value="1,2,3-6,7-9,10-15,16,17-19" />
                    <property name="strict" value="false" />
                </bean>
            </property>
            <property name="fieldSetMapper">
                <bean class="com.example.batch.acct.AcctInputFieldSetMapper" />
            </property>
        </bean>
    </property>
</bean>

<bean id="processor" class="com.example.batch.acct.AcctProcessor" scope="step">
    <property name="soapClient"  ref="soapClient" />
    <property name="maxNumIds"   value="${batch.soap.numberOfIds}" />
    <aop:scoped-proxy />
</bean>

Answer 1

<bean id="itemProcessor" class="com.myApp.MyItemProcessor" scope="step">
    <property name="stepContext" value="#{stepExecutionContext}"/>
</bean>

在这种情况下，当stepContex是org的一种类型时。springframework。一批果心范围上下文StepContext，如何显示此属性的名称，我遇到了异常：

组织。springframework。豆。工厂BeanCreationException:创建名为“scopedTarget”的bean时出错。在类路径资源[META-INF/jobs/Job.xml]中定义的itemProcessor'：bean初始化失败；嵌套的异常是org。springframework。豆。ConversionNotSupportedException:未能转换“java”类型的属性值。util。集合$UnmodifiableMap“到所需类型”组织。springframework。一批果心范围上下文属性“StepContext”的“StepContext”；嵌套的异常是java。lang.IllegalStateException:无法转换“java”类型的值。util。集合$UnmodifiableMap“到所需类型”组织。springframework。一批果心范围上下文属性“StepContext”的“StepContext”：未找到匹配的编辑器或转换策略

我需要访问ItemProcessor内部的jobExecutionId，因此我已将此配置更改为：

<bean id="itemProcessor" class="com.myApp.MyItemProcessor" scope="step">
    <property name="stepExecution" value="#{stepExecution}"/>
</bean>

属性“stepExecution”是一种类型组织。springframework。一批果心步骤执行

Answer 2

在Spring Batch论坛上回答：

ItemProcessor接口没有公开访问StepContext的方法，因此您需要自己插入它：

<bean id="itemProcessor" class="com.myApp.MyItemProcessor" scope="step">
    <property name="stepContext" value="#{stepExecutionContext}"/>
</bean>

假设您的处理器类有一个名为stepContext的公开属性。

_{-Michael Minella，Spring Batch负责人}