Spring Batch - Read once and write twice

Question

I am new to Spring Batch. My requirement is I have a reader which gets the records through a web service call/database call and currently I am writing those records to one table. Now I need same records (records read by reader) needs to be processed and write into another table. The point to note here is the second items those are getting stored in second write are of different type of first write.

I need like below

1st Step: - Read items of type A --> Write items of Type A 
2nd Step:-  Read items of type A --> Process to type B ---> Write 10 items of type B

For the same above job I need Transaction Management. Also, in Step-2 :- If possible, I should use the data which was already read in Step-1.

Is your process: Read type A -> Write Table A -> Read type A -> Process into type B -> write 10 type B? — Michael Minella, Sep 15 '14 at 15:30
Thanks For the Reply Michael Minella Yes exactly... Read type A --> Write Type A Read type A --> Process to typeB ---> Write 10type B ***Two things here, if possible i also need these below things for Job --> Transaction Management --> Commit interval concept --> Type A should be read once only(Like i should hold that data some where, to use in second Write process) — StackOverFlow Newbie, Sep 15 '14 at 19:14
Can you please update your question with those notes so they are a bit more readable? — Michael Minella, Sep 15 '14 at 21:13
@Michael Minella : Edited the question, please see and help me out. Thanks in advance — StackOverFlow Newbie, Sep 16 '14 at 02:47

score 0 · Accepted Answer · answered Sep 16 '14 at 14:42

Spring Batch defines independent steps for processing. Each step is responsible for their input, processing, and output. Because of this, I'd structure the job something like:

<job id="myJob">
    <step id="step1" next="step2">
        <tasklet>
            <chunk reader="reader" writer="typeAwriter"/>
        </tasklet>
    </step>
    <step id="step2">
        <tasklet>
            <chunk reader="reader" processor="processor" writer="typeBwriter"/>
        </tasklet>
    </step>
</job>

With the above configuration, the reader would be a step scoped reader that reads in type A. The typeAwriter writes out type A. The processor is the processor that converts type A to type B. The typeBwriter writes type B. Since the processor returns a list of type B, the typeBwriter would need to be a custom implementation that loops over the lists that the processor returns (typeBwriter would take a List<List<TypeB>>).

Spring Batch - Read once and write twice

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