Create new output file using FlatFileItemWriter in spring-batch

Question

I have a simple spring batch job - read a file line by line, do something with the input string, and write some output. Output file contains every line of input plus some processing status for that line (success/failure.) The reads a file from: <dir>/<inputFolder>/<inputFileName> and writes processed output to <dir>/<outputFolder>/<inputFileName> All these values are passed as jobParameters
File Reader is like so:

<bean id="itemReader" class="org.springframework.batch.item.file.FlatFileItemReader" scope="step">
        <property name="resource" value="file:#{jobParameters['cwd']}/#{jobParameters['inputFolder']}/#{jobParameters['inputFile']}" />

        <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="," />
              </bean>
            </property>
            <property name="fieldSetMapper" >
              <bean class="org.springframework.batch.item.file.mapping.PassThroughFieldSetMapper" />
            </property>
          </bean>
        </property>
    </bean>

Item writer is like so:

<bean id="itemWriter" class="org.springframework.batch.item.file.FlatFileItemWriter" scope="step" >
        <property name="resource" value="#{jobParameters['cwd']}/#{jobParameters['outputFolder']}/#{jobParameters['inputFile']}" />
        <property name="lineAggregator">
            <bean class="org.springframework.batch.item.file.transform.PassThroughLineAggregator" />
        </property>
    </bean>  

When I run this batch job, the reader reads the file properly, processor does its job but FileNotFound exception is thrown by the itemWriter

2014/06/27 18-02-31,168:OUT:ERROR[Encountered an error executing the step]
org.springframework.batch.item.ItemStreamException: Could not convert resource to file: [class path resource [S:/temp/seller-optin-batch/output/sellersToOptin_test.txt]]
    at org.springframework.batch.item.file.FlatFileItemWriter.getOutputState(FlatFileItemWriter.java:374)
    at org.springframework.batch.item.file.FlatFileItemWriter.open(FlatFileItemWriter.java:314)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
...
    Caused by: java.io.FileNotFoundException: class path resource [S:/temp/seller-optin-batch/output/sellersToOptin_test.txt] cannot be resolved to URL because it does not exist
        at org.springframework.core.io.ClassPathResource.getURL(ClassPathResource.java:179)
        at org.springframework.core.io.AbstractFileResolvingResource.getFile(AbstractFileResolvingResource.java:48)
        at org.springframework.batch.item.file.FlatFileItemWriter.getOutputState(FlatFileItemWriter.java:371)
        ... 58 more
    2014/06/27 18-02-31,168:ERR:ERROR[Encountered an error executing the step]

    [org.springframework.batch.item.file.FlatFileItemWriter.getOutputState threw org.springframework.batch.item.ItemStreamException: Could not convert resource to file: [class path resource [S:/temp/seller-optin-batch/output/sellersToOptin_test.txt]]]
    Batch Execution Failed!

Everytime the batch job runs, the output file does not exist yet. The itemWriter has to create it. Is it not possible using FlatFileItemWriter ?

Answer 1

Adding 'file://' prefix solved my problem. Thanks @LucaBassoRicci.