Spring Batch -使用Flatfilewriter将List<List<>>从阅读器写入CSV

<bean id="itemReader" class="org.springframework.batch.item.file.FlatFileItemReader">
    <property name="resource" value="classpath:data.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="names" value="column1,column2,column3" />
                </bean>
            </property>
            <property name="fieldSetMapper">
                <bean class="org.springframework.batch.item.file.mapping.BeanWrapperFieldSetMapper">
                    <property name="targetType" value="com.example.MyData" />
                </bean>
            </property>
        </bean>
    </property>
</bean>

<bean id="itemProcessor" class="com.example.MyItemProcessor" />

<bean id="itemWriter" class="org.springframework.batch.item.file.FlatFileItemWriter">
    <property name="resource" value="file:output.csv" />
    <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="column1,column2,column3" />
                </bean>
            </property>
        </bean>
    </property>
</bean>

<batch:job id="myJob">
    <batch:step id="step1">
        <batch:tasklet>
            <batch:chunk reader="itemReader" processor="itemProcessor" writer="itemWriter" commit-interval="10" />
        </batch:tasklet>
    </batch:step>
</batch:job>