Batch Decision

Run
How to run the sample
The source code for this sample can be found in the javaee7-samples GitHub repository. The first thing we need to do is to get the source by downloading the repository and then go into the samples folder:
git clone git://github.com/javaee-samples/javaee7-samples.git
cd javaee7-samples/batch/decision/
Now we are ready to start testing. You can run all the tests in this sample by executing:
mvn test
Or you can run individual tests by executing one of the following:
mvn test -Dtest=BatchDecisionTest

Batch DSL - Decision

BatchDecisionTest

The Batch specification allows you to implement process workflow using a Job Specification Language (JSL). In this sample, by using the decision element, it’s possible to configure a job that follows different paths of execution based on your own criteria by implementing a Decider

The Decider just needs to return a meaningful value, to use in the myJob.xml file to be able to reference the next step that must be executed.

<?xml version="1.0" encoding="UTF-8"?>
<job id="myJob" xmlns="http://xmlns.jcp.org/xml/ns/javaee" version="1.0">
    <step id="step1" next="decider1">
        <batchlet ref="myBatchlet1"/>
    </step>
    <decision id="decider1" ref="myDecider">
        <next on="foobar" to="step3"/>


        <stop on="foobar2" exit-status="foobar3" restart="step3"/>
    </decision>
    <step id="step2">
        <batchlet ref="myBatchlet2"/>
    </step>
    <step id="step3">
        <batchlet ref="myBatchlet3"/>
    </step>
</job>

Three Steps and one Decider are configured in the file myJob.xml. We start by executing one step1 and hand over the control to the Decider, which will execute step2, since the Decider is always returning the value foobar which forwards the execution to step2.

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.decision")
            .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 JobOperator#getStepExecutions and the Metric object available in the step execution.

@Test
public void testBatchDecision() 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);
    List<String> executedSteps = new ArrayList<>();
    for (StepExecution stepExecution : stepExecutions) {
        executedSteps.add(stepExecution.getStepName());
    }

    (1)
    assertEquals(2, stepExecutions.size());
    (2)
    assertArrayEquals(new String[] {"step1", "step3"}, executedSteps.toArray());
    (3)
    assertFalse(executedSteps.contains("step2"));
    (4)
    assertEquals(BatchStatus.COMPLETED, jobExecution.getBatchStatus());
}
  1. Make sure that only two steps were executed.

  2. Make sure that only the expected steps were executed an in order.

  3. Make sure that this step was never executed.

  4. Job should be completed.

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Recent Changelog

  • Dec 14, 2014: Switch from polling on jobexecution (for job completion) to polling with joboperator and executionid by Scott Kurz
  • Jul 05, 2014: Removed header license for batch xml files by Roberto Cortez
  • Jun 22, 2014: Removed header license. the licensing is now referenced in the license file in the root of the project by Roberto Cortez
  • Jun 20, 2014: Added fqn to java ee api references to generate direct links to javadocs by radcortez
  • Jun 19, 2014: Documentation clarifications and typos by radcortez
  • Jun 12, 2014: Fix callout numbering in batchdecisiontest by Aslak Knutsen
  • Jun 12, 2014: Added documentation to decision project by Roberto Cortez
  • Dec 31, 2013: Removed servlets and jsp's by Roberto Cortez
  • Dec 30, 2013: Added test for decision project by Roberto Cortez
  • Sep 17, 2013: Removing netbeans configuration file by Arun Gupta
How to help improve this sample
The source code for this sample can be found in the javaee7-samples GitHub repository. The first thing you need to do is to get the source by downloading the repository and then go into the samples folder:
git clone git://github.com/javaee-samples/javaee7-samples.git
cd javaee7-samples/batch/decision/

Do the changes as you see fit and send a pull request!

Good Luck!