如何使用Spring Batch读取具有不同列数的CSV文件 [英] How to read CSV file with different number of columns with Spring Batch

问题描述

我有一个没有固定列数的CSV文件，例如:

I have a CSV file that doesn't have a fixed number of columns, like this:

  col1,col2,col3,col4,col5    
  val1,val2,val3,val4,val5 
  column1,column2,column3
  value1,value2,value3

是否可以使用Spring Batch读取此类CSV文件?

Is there any way to read this kind of CSV file with Spring Batch?

我试图这样做:

<bean id="ItemReader" class="org.springframework.batch.item.file.FlatFileItemReader">

    <!-- Read a csv file -->
    <property name="resource" value="classpath:file.csv" />

    <property name="lineMapper">
        <bean class="org.springframework.batch.item.file.mapping.DefaultLineMapper">
            <!-- split it -->
            <property name="lineTokenizer">
                <bean
                    class="org.springframework.batch.item.file.transform.DelimitedLineTokenizer">
                    <property name="names"
                        value="col1,col2,col3,col4,col5,column1,column2,column3" />
                </bean>
            </property>
            <property name="fieldSetMapper">
                <bean
                    class="org.springframework.batch.item.file.mapping.BeanWrapperFieldSetMapper">
                    <property name="prototypeBeanName" value="myBean" />
                </bean>
            </property>

        </bean>
    </property>

</bean>

但是结果是这个错误:

推荐答案

您可以根据模式使用PatternMatchingCompositeLineMapper每行委派给相应的LineMapper实现.从那里，您的每个代表将使用DelimtedLineTokenizer和FieldSetMapper来相应地映射线.

You can use the PatternMatchingCompositeLineMapper to delegate to the appropriate LineMapper implementation per line based on a pattern. From there, each of your delegates would use a DelimtedLineTokenizer and a FieldSetMapper to map the line accordingly.

您可以在以下文档中详细了解此内容: http://docs.spring.io/spring-batch/trunk/apidocs/org/springframework/batch/item/file/mapping/PatternMatchingCompositeLineMapper.html

You can read more about this in the documentation here: http://docs.spring.io/spring-batch/trunk/apidocs/org/springframework/batch/item/file/mapping/PatternMatchingCompositeLineMapper.html

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