implementing batch processing in java ee 7 2014...batch - javaland 2014 @ivar_grimstad implementing...

Batch - JavaLand 2014 @ivar_grimstad

Implementing Batch Processing in Java EE 7Ivar Grimstad

Ivar Grimstad

About

Batch - JavaLand 2014 @ivar_grimstad

@ivar_grimstad

batch (plural batches)

The quantity of bread or other baked goods baked at one time.

We made a batch of cookies to take to the party.

Batch - JavaLand 2014 @ivar_grimstad

Source: http://en.wiktionary.org/wiki/batch

• Batch Applications

• Batch in Java EE 7

• Demo

• Wrap-Up

Content

Batch - JavaLand 2014 @ivar_grimstad

History

Batch - JavaLand 2014 @ivar_grimstad

Batch Applications

Batch - JavaLand 2014 @ivar_grimstad

• Bulk database updates

• Image processing

• Conversions

Common Usages

Batch - JavaLand 2014 @ivar_grimstad

• No User Interaction

• Utilize Batch Windows

• Repetitive Work

Advantages of Batch Processing

Batch - JavaLand 2014 @ivar_grimstad

• Training

• Difficult Debugging

• Costly

Disadvantages of Batch Processing

Batch - JavaLand 2014 @ivar_grimstad

Batch Frameworks

To The Rescue

Batch - JavaLand 2014 @ivar_grimstad

• Jobs, steps, decision elements, relationships

• Parallel or sequential processing

• State

• Launch, pause and resume

• Error handling

Batch Frameworks

Batch - JavaLand 2014 @ivar_grimstad

Large Data Volume

Automation

Robustness

Reliability

Performance

Requirements of Batch Applications

Batch - JavaLand 2014 @ivar_grimstad

Batch - JavaLand 2014 @ivar_grimstad

Batch Processing in Java EE 7

• Batch Runtime

• Job Specification

• Java API

–Runtime interaction

– Implementation

The Batch Processing Framework

Batch - JavaLand 2014 @ivar_grimstad

• Start jobs

• Check status of jobs

Batch Runtime

Batch - JavaLand 2014 @ivar_grimstad

• Steps

• Flows

• Splits

• Decision Elements

Job Specification

Batch - JavaLand 2014 @ivar_grimstad

Job Specification Language (JSL)

Batch - JavaLand 2014 @ivar_grimstad

<job>

<listeners>

<listener />

</listeners>

<properties>

<property />

</properties>

<step ...> ... </step>

<step ...> ... </step>

<decision ...> ... </decision>

<flow ...> ... </flow>

<split ...> ... </split>

</job>

Java Batch API (task oriented)

Batch - JavaLand 2014 @ivar_grimstad

Package Interface Description

javax.batch.api BatchletImplements the business logic of a task-oriented

step.

Java Batch API (chunk oriented)

Batch - JavaLand 2014 @ivar_grimstad

Package Interface Description

javax.batch.api.chunk ItemReaderReads items from an input source in a

chunk step.

javax.batch.api.chunk ItemProcessorProcesses input items to obtain output

items in chunk steps.

javax.batch.api.chunk ItemWriter Writes output items in chunk steps.

ItemReader ItemWriterItemProcessor

Chunk Oriented Steps

Batch - JavaLand 2014 @ivar_grimstad

Item

Dependency Injection

Batch - JavaLand 2014 @ivar_grimstad

@Dependent

@Named("MyItemReader")

public class MyItemReaderImpl implements ItemReader {

}

<step id="stepA" next="stepB">

<chunk>

<reader ref="MyItemReader"></reader>

...

</chunk>

</step>

Batch Runtime API

Batch - JavaLand 2014 @ivar_grimstad

@Dependent

@Named("MyItemReader")

public class MyItemReaderImpl implements ItemReader {

@Inject

JobContext jobCtx;

@Inject

StepContext stepCtx;

}

Invocation

Batch - JavaLand 2014 @ivar_grimstad

jobOperator = BatchRuntime.getJobOperator();

Properties props = new Properties();

props.setProperty("parameter1", "value1");

long execID = jobOperator.start("simplejob", props);

EJB, Servlet, ManagedBean etc.

• No separate packaging needed

• Can be included in any Java EE application

–META-INF/batch-jobs/

–WEB-INF/classes/META-INF/batch-jobs/

Packaging

Batch - JavaLand 2014 @ivar_grimstad

Monitoring

Batch - JavaLand 2014 @ivar_grimstad

Package Interface Description

javax.batch.runtime JobExecutionProvides methods to obtain information

about submitted jobs.

JobExecution jobExec = jobOperator.getJobExection(id);

String status = jobExec.getBatchStatus().toString();

• Design the application

• Create batch artifacts

• Define jobs, steps and execution flow

• Launch batch application

Creating a Java EE Batch Application

Batch - JavaLand 2014 @ivar_grimstad

Batch - JavaLand 2014 @ivar_grimstad

DEMO

• Create a simple batchlet

• Create a simple chunk oriented job

• Package in a WAR

• Start jobs from a Servlet

• Schedule jobs from Timer EJB

Demo Steps

Batch - JavaLand 2014 @ivar_grimstad

Simple Batchlet

Batch - JavaLand 2014 @ivar_grimstad

Simple Chunk Oriented

Batch - JavaLand 2014 @ivar_grimstad

• Created a simple batchlet

• Created a simple chunk oriented job

• Packaged application in a WAR

• Started jobs from a Servlet

• Scheduled jobs from Timer EJB

Demo Steps (what we did)

Batch - JavaLand 2014 @ivar_grimstad

Batch - JavaLand 2014 @ivar_grimstad

Summary

…but isn’t it?

Batch - JavaLand 2014 @ivar_grimstad

• Simple and Flexible

• Clear and precise API

• No separate packaging required

• Is a part of Java EE

Summary

Batch - JavaLand 2014 @ivar_grimstad

https://github.com/ivargrimstad/javaee-batch

Sources

Batch - JavaLand 2014 @ivar_grimstad

Batch - JavaLand 2014 @ivar_grimstad