Dinesh on Java

Spring Batch Tutorial : Introduction-

Many applications within the enterprise domain require bulk processing to perform business operations in mission critical environments. These business operations include automated, complex processing of large volumes of information that is most efficiently processed without user interaction. These operations typically include time based events (e.g. month-end calculations, notices or correspondence), periodic application of complex business rules processed repetitively across very large data sets (e.g. insurance benefit determination or rate adjustments), or the integration of information that is received from internal and external systems that typically requires formatting, validation and processing in a transactional manner into the system of record. Batch processing is used to process billions of transactions every day for enterprises.

Spring Batch-

Spring Batch is a lightweight, comprehensive batch framework designed to enable the development of robust batch applications vital for the daily operations of enterprise systems. Spring Batch builds upon the productivity, POJO-based development approach, and general ease of use capabilities people have come to know from the Spring Framework, while making it easy for developers to access and leverage more advanced enterprise services when necessary.

Spring Batch provides reusable functions that are essential in processing large volumes of records, including logging/tracing, transaction management, job processing statistics, job restart, skip, and resource management. It also provides more advanced technical services and features that will enable extremely high-volume and high performance batch jobs through optimization and partitioning techniques. Simple as well as complex, high-volume batch jobs can leverage the framework in a highly scalable manner to process significant volumes of information.

High Level Architecture:-

In above figure, the top of the hierarchy is the batch application itself. This is whatever batch processing application you want to write. It depends on the Spring Batch core module, which primarily provides a runtime environment for your batch jobs. Both the batch app and the core module in turn depend upon an infrastructure module that provides classes useful for both building and running batch apps.

As we see in above figure a hypothetical three-step job, though obviously a job can have arbitrarily many steps. The steps are typically sequential, though as of Spring Batch 2.0 it’s possible to define conditional flows (e.g., execute step 2 if step 1 succeeds; otherwise execute step 3). Within any given step, the basic process is as follows: read a bunch of “items” (e.g., database rows, XML elements, lines in a flat file—whatever), process them, and write them out somewhere to make it convenient for subsequent steps to work with the result.
Overview of the Spring Batch Core- The Spring Batch Core Domain consists of an API for launching, monitoring and managing batch jobs.

The figure above shows the central parts of the core domain and its main touch points with the batch application developer (Job and Step). To launch a job there is a JobLauncher interface that can be used to simplify the launching for dumb clients like JMX or a command line.