我在 spring 批处理中实现了一个步骤,该步骤从数据库中读取记录并生成输出文件。该步骤已分区,以便每个从步骤生成不同的文件。然后我实现了一个在从属之后执行的步骤,它所做的是读取这些中的每一个生成的文件并将它们合并为单个文件(合并)。
我遇到的问题是,当运行合并器步骤时,输入文件为空(可能是因为未执行刷新),然后尝试在从属编写器中配置 forceSync = true 和事务 = false,但没有效果。
当他们完成作业时,从属生成的文件包含数据,合并文件为空。那么,问题是在执行合并器步骤时输入文件是空的。
可以帮助我吗?,需要更多信息?
(对不起我的英语)
谢谢
<batch:job id="interfacesJob" xmlns="">
<batch:step id="step.1" parent="readerParent" next="step.2"/>
<batch:step id="step.2" parent="merge"/>
</batch:job>
<batch:step id="readerParent">
<batch:partition step="slave" partitioner="partitioner">
<batch:handler grid-size="50" task-executor="poolTaskExecutor" />
</batch:partition>
</batch:step>
<batch:step id="slave">
<batch:tasklet
transaction-manager="transactionManager">
<batch:chunk
reader="dummyReader"
processor="dummyProcessor"
writer="dummyWriter"
commit-interval="1"
skip-limit="50">
</batch:tasklet>
</batch:step>
<bean id="dummyWriter"
class="org.springframework.batch.item.file.FlatFileItemWriter"
scope="step" >
<property name="resource" value="file:operations_#{stepExecutionContext[fromId]}.txt" />
<property name="forceSync" value="true" />
<property name="transactional" value="false" />
<property name="lineAggregator">
<bean class="org.springframework.batch.item.file.transform.DelimitedLineAggregator">
<property name="delimiter" value="," /> <!-- default -->
<property name="fieldExtractor">
<bean class="org.springframework.batch.item.file.transform.BeanWrapperFieldExtractor">
<property name="names" value="id,field1,field2" />
</bean>
</property>
</bean>
</property>
</bean>
<batch:step id="merge">
<tasklet>
<chunk reader="mergeReader" writer="mergeWriter" commit-interval="1" />
</tasklet>
</batch:step>
<bean id="mergeReader"
class="org.springframework.batch.item.file.FlatFileItemReader">
<property name="resources" value="file:operations_*.txt" />
<property name="lineMapper">
<bean class="org.springframework.batch.item.file.mapping.DefaultLineMapper">
<property name="lineTokenizer">
<bean class="org.springframework.batch.item.file.transform.DelimitedLineTokenizer">
<property name="delimiter" value="," />
<property name="names" value="id,field1,field2" />
</bean>
</property>
<property name="fieldSetMapper">
<bean class="org.springframework.batch.item.file.mapping.BeanWrapperFieldSetMapper">
<property name="prototypeBeanName" value="dummyPrototypeBean" />
</bean>
</property>
</bean>
</property>
</bean>
<bean id="mergeWriter"
class="org.springframework.batch.item.file.FlatFileItemWriter">
<property name="resource" value="file:final.txt" />
<property name="lineAggregator">
<bean class="org.springframework.batch.item.file.transform.DelimitedLineAggregator">
<property name="delimiter" value="," />
<property name="fieldExtractor">
<bean class="org.springframework.batch.item.file.transform.BeanWrapperFieldExtractor">
<property name="names" value="id,field1,field2" />
</bean>
</property>
</bean>
</property>
</bean>
我用 MultiResourceItemReader 来尝试合并阅读器,但仍然继续遇到同样的问题:
<bean id="mergeReader"
class="org.springframework.batch.item.file.MultiResourceItemReader">
<property name="resources" value="file:operations_*.txt" />
<property name="delegate" ref="mergeReaderSpecific" />
</bean>
<bean id="mergeReaderSpecific"
class="org.springframework.batch.item.file.FlatFileItemReader">
<property name="lineMapper">
<bean class="org.springframework.batch.item.file.mapping.DefaultLineMapper">
<property name="lineTokenizer">
<bean class="org.springframework.batch.item.file.transform.DelimitedLineTokenizer">
<property name="delimiter" value="," />
<property name="names" value="id,field1,field2" />
</bean>
</property>
<property name="fieldSetMapper">
<bean class="org.springframework.batch.item.file.mapping.BeanWrapperFieldSetMapper">
<property name="prototypeBeanName" value="dummyPrototypeBean" />
</bean>
</property>
</bean>
</property>
</bean>
可能你必须使用MultiResourceItemReader作为mergeReader
使用FlatFileItemReader
作为委托。
FlatFileItemReader.resource
属性旨在用于与 MultiResourceItemReader.resources
(复数)。