Spring Batch - TaskletStep中的可跳过异常

Question

I am trying to cause a job not to have BatchStatus.FAILED if a certain exception occurs.

The docs talk about using skippable-exception-classes within <chunk> , but how can I do the same within a TaskletStep ? The below code does not work:

<batch:step id="sendEmailStep">
    <batch:tasklet>
        <bean class="com.myproject.SendEmail" scope="step" autowire="byType">
            <batch:skippable-exception-classes>
                <batch:include class="org.springframework.mail.MailException" />
            </batch:skippable-exception-classes>
        </bean>
    </batch:tasklet>
</batch:step>

Answer 1

I implemented this functionality in the Tasklet as Michael Minella suggested:

abstract class SkippableTasklet implements Tasklet {

    //Exceptions that should not cause job status to be BatchStatus.FAILED
    private List<Class<?>> skippableExceptions;

    public void setSkippableExceptions(List<Class<?>> skippableExceptions) {
        this.skippableExceptions = skippableExceptions;
    }

    private boolean isSkippable(Exception e) {
        if (skippableExceptions == null) {
            return false;
        }

        for (Class<?> c : skippableExceptions) {
            if (e.getClass().isAssignableFrom(c)) {
                return true;
            }
        }
        return true;
    }

    protected abstract void run(JobParameters jobParameters) throws Exception;

    @Override
    public RepeatStatus execute(StepContribution contribution, ChunkContext chunkContext)
            throws Exception {

        StepExecution stepExecution = chunkContext.getStepContext().getStepExecution();
        JobExecution jobExecution = stepExecution.getJobExecution();
        JobParameters jobParameters = jobExecution.getJobParameters();

        try {
            run(prj);
        } catch (Exception e) {
            if (!isSkippable(e)) {
                throw e;
            } else {
                jobExecution.addFailureException(e);
            }
        }

        return RepeatStatus.FINISHED;
    }
}

And the Spring XML configuration for an example SkippableTasklet :

<batch:tasklet>
    <bean class="com.MySkippableTasklet" scope="step" autowire="byType">
        <property name="skippableExceptions">
            <list>
                <value>org.springframework.mail.MailException</value>
            </list>
        </property>
    </bean>
</batch:tasklet>

Answer 2

Within a Tasklet , the responsibility for exception handling is on the implementation of the Tasklet . The skip logic available in chunk oriented processing is due to the exception handling provided by the ChunkOrientedTasklet . If you want to skip exceptions in your own Tasklet implementation, you need to write the code to do so in within your own implementation.