CHAPTER 1 BATCH AND SPRING
2
A History of Batch Processing
To look at the history of batch processing, you really need to look at the history of computing itself.
The time was 1951. The UNIVAC became the first commercially produced computer. Prior to this
point, computers were each unique, custom-built machines designed for a specific function (for
example, in 1946 the military commissioned a computer to calculate the trajectories of artillery shells).
The UNIVAC consisted of 5,200 vacuum tubes, weighed in at over 14 tons, had a blazing speed of
2.25MHz (compared to the iPhone 4, which has a 1GHz processor) and ran programs that were loaded
from tape drives. Pretty fast for its day, the UNIVAC was considered the first commercially available
batch processor.
Before going any further into history, I should define what, exactly, batch processing is. Most of the
applications you develop have an aspect of user interaction, whether it’s a user clicking a link in a web
app, typing information into a form on a thick client, or tapping around on phone and tablet apps. Batch
processing is the exact opposite of those types of applications. Batch processing, for this book’s purposes,
is defined as the processing of data without interaction or interruption. Once started, a batch process
runs to some form of completion without any intervention.
Four years passed in the evolution of computers and data processing before the next big change:
high-level languages. They were first introduced with Lisp and Fortran on the IBM 704, but it was the
Common Business Oriented Language (COBOL) that has since become the 800-pound gorilla in the
batch-processing world. Developed in 1959 and revised in 1968, 1974, and 1985, COBOL still runs batch
processing in modern business. A Gartner study
1
estimated that 60% of all global code and 85% of global
business data is housed in the language. To put this in perspective, if you printed out all that code and
stacked the printout, you’d have a stack 227 miles high. But that’s where the innovation stalled.
COBOL hasn’t seen a significant revision in a quarter of a century.
2
The number of schools that
teach COBOL and its related technologies has declined significantly in favor of newer technologies like
Java and .NET. The hardware is expensive, and resources are becoming scarce.
Mainframe computers aren’t the only places that batch processing occurs. Those e-mails I
mentioned previously are sent via batch processes that probably aren’t run on mainframes. And the
download of data from the point-of-sale terminal at your favorite fast food chain is batch, too. But there
is a significant difference between the batch processes you find on a mainframe and those typically
written for other environments (C++ and UNIX, for example). Each of those batch processes is custom
developed, and they have very little in common. Since the takeover by COBOL, there has been very little
in the way of new tools or techniques. Yes, cron jobs have kicked off custom-developed processes on
UNIX servers and scheduled tasks on Microsoft Windows servers, but there have been no new industry-
accepted tools for doing batch processes.
Until now. In 2007, Accenture announced that it was partnering with Interface21 (the original
authors of the Spring framework, and now SpringSource) to develop an open source framework that
would be used to create enterprise batch processes. As Accenture’s first formal foray into the open
source world, it chose to combine its expertise in batch processing with Spring’s popularity and feature
set to create a robust, easy-to-use framework. At the end of March 2008, the Spring Batch 1.0.0 release
was made available to the public; it represented the first standards-based approach to batch processing
in the Java world. Slightly more than a year later, in April 2009, Spring Batch went 2.0.0, adding features
like replacing support for JDK 1.4 with JDK 1.5+, chunk-based processing, improved configuration
options, and significant additions to the scalability options within the framework.
1
http://www.gartner.com/webletter/merant/article1/article1.html
2
There have been revisions in COBOL 2002 and Object Oriented COBOL, but their adoption has been
significantly less than for previous versions.
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