Spring Batch is a lightweight, Open Source batch processing framework designed to handle the day-to-day batch processing jobs involving bulk of data. Batch processing is execution of series of job where each job may involve multiple steps.
Source : Spring Batch Reference
A Job is composed of one to many Steps. Each Step can work in two modes :
- Chunk Oriented Processing or READ-PROCESS-WRITE mode: Step needs to read from a resource , process the data and then write back the process data to a resource. In this approach, Step has exactly one ItemReader(reader which reads from a resource, be it file, database, messaging queue etc.), ItemProcessor ( provides a hook to apply business logic) and ItemWriter (writer which writes to a resource, be it file, database, messaging queue etc).
- TASKLET mode: Step has to perform a single operation (be it just sending email, executing a stored procedure, cleaning up files older than x days, etc). In this approach Step includes a Tasklet interface which have only one method execute which can perform above mentioned activities. A job is launched via JobLauncher, and JobRepository stores the meta data about the currently running process.Note that Steps can be chained together.