title: Data Migration using Spring Batch
body: <p>I am migrating a java application already written to Spring batch. This application will do data migration across 2 different environment. The application is designed as below</p>
  
  <p>1) To read a set of user id from source DB based on some flag.</p>
  
  <p>2) read the user specific data from 3 different database in the source environment for each user.</p>
  
  <p>3) write the data in the destination database for each user.</p>
  
  <p>I also need to implement parallel processing, so that at a time 10 or more threads will run and each thread will be responsible for migration of a individual user’s data. </p>
  
  <p>I am completely new to spring and so having problem to visualizing the structure of my configuration xml. I am thinking of having a step to read the set of user Id first and then pass it to the second step, which will be responsible for reading user specific data, and writing it. But I am having problems while implementing the same. It will really help me if someone can suggest me a structure of the same in the context of spring batch, with parallel processing </p>