JavaEE Sample::Batch::Batch Chunk Optional Processor

BatchChunkOptionalProcessorTest

The Batch specification provides a Chunk Oriented processing style. This style is defined by enclosing into a transaction a set of reads, process and write operations via ItemReader, ItemProcessor and ItemWriter. Items are read one at a time, processed and aggregated. The transaction is then committed when the defined checkpoint-policy is triggered.

<?xml version="1.0" encoding="UTF-8"?>
<job id="myJob" xmlns="http://xmlns.jcp.org/xml/ns/javaee" version="1.0">
    <step id="myStep" >
        <chunk item-count="3">
            <reader ref="myItemReader"/>
            <writer ref="myItemWriter"/>
        </chunk>
    </step>
</job>

A very simple job is defined in the myJob.xml file. The processor is optional, so this is just a single step with a reader and a writer.

We’re just going to deploy the application as a web archive. Note the inclusion of the following files:

/META-INF/batch-jobs/myJob.xml

The myJob.xml file is needed for running the batch definition.

@Deployment
public static WebArchive createDeployment() {
    WebArchive war = ShrinkWrap.create(WebArchive.class)
            .addClass(BatchTestHelper.class)
            .addPackage("org.javaee7.batch.chunk.optional.processor")
            .addAsWebInfResource(EmptyAsset.INSTANCE, ArchivePaths.create("beans.xml"))
            .addAsResource("META-INF/batch-jobs/myJob.xml");
    System.out.println(war.toString(true));
    return war;
}

In the test, we’re just going to invoke the batch execution and wait for completion. To validate the test expected behaviour we need to query the Metric object available in the step execution.

The batch process itself will read 10 elements from numbers 1 to 10, and write the same elements. Commits are executed after 3 elements are read.

@Test
public void testBatchChunkOptionalProcessor() throws Exception {
    JobOperator jobOperator = BatchRuntime.getJobOperator();
    Long executionId = jobOperator.start("myJob", new Properties());
    JobExecution jobExecution = jobOperator.getJobExecution(executionId);

    jobExecution = BatchTestHelper.keepTestAlive(jobExecution);

    List<StepExecution> stepExecutions = jobOperator.getStepExecutions(executionId);
    for (StepExecution stepExecution : stepExecutions) {
        if (stepExecution.getStepName().equals("myStep")) {
            Map<Metric.MetricType, Long> metricsMap = BatchTestHelper.getMetricsMap(stepExecution.getMetrics());

            (1)
            assertEquals(10L, metricsMap.get(Metric.MetricType.READ_COUNT).longValue());
            (2)
            assertEquals(10L, metricsMap.get(Metric.MetricType.WRITE_COUNT).longValue());
            (3)
            assertEquals(10L / 3 + (10L % 3 > 0 ? 1 : 0),
                         metricsMap.get(Metric.MetricType.COMMIT_COUNT).longValue());
        }
    }

    (4)
    assertEquals(BatchStatus.COMPLETED, jobExecution.getBatchStatus());
}

The read count should be 10 elements. Check MyItemReader.
The write count should be same 10 read elements.
The commit count should be 4. Checkpoint is on every 3rd read, 4 commits for read elements.
Job should be completed.

Batch Chunk Optional Processor

Chunk Processing - Read and Write

BatchChunkOptionalProcessorTest

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