The Ultimate Beginner’s Guide For Spring Batch Error Handling

Summary

This article provides a beginner's guide to Spring Batch error handling, covering key concepts such as restart, retry, and skip, with examples and configuration links.

Abstract

The article "The Ultimate Beginner’s Guide For Spring Batch Error Handling" introduces key concepts for handling errors in Spring Batch, a popular framework for batch processing in Java. The author explains the default behavior of Spring Batch when an uncaught exception occurs during job processing, which is to stop the job and pick up where it left off when restarted. The article also covers Spring Batch's integration with Spring Retry for retrying multiple times until a maximum retry count is reached, and the ability to configure skipping failures based on specific exceptions. The author provides examples and links to configuration details for each concept, as well as information on setting up custom listeners for logging or taking appropriate actions. The article concludes with a reference to a video course on Learning Spring Batch.

Bullet points

Spring Batch stops the job and picks up where it left off when restarted after an uncaught exception.
Spring Batch can integrate with Spring Retry to retry multiple times until a maximum retry count is reached.
ItemProcessor and ItemWriter are retryable, but ItemReader is not.
Custom RetryListeners can be set up to log or take appropriate actions.
Spring Batch allows for skipping failures based on specific exceptions and the number of items that can be skipped.
Custom SkipListeners can be set up to log errors or take appropriate actions.
The article provides examples and links to configuration details for each concept.
The article concludes with a reference to a video course on Learning Spring Batch.

Restart

By default , if there’s an uncaught exception when processing the job, spring batch will stop the job. If the job is restarted with the same job parameters, it will pick up where it left off. The way it knows where the job status is by checking the job repository where it saves all the spring batch job status.

Let’s say for example if your job failed at step 2 for the 100th record, spring batch will stop the job processing. When the job is restarted, it will start at step 2 for the 100th record, since step 1 for 100th record is already successfully processed.

You can see more details for how to configure restart here.

restart example from spring.io

Retry

Spring batch can integrate with spring retry to retry multiple times until it maxed out the retry count that it’s configured. You can also specify specific exception that allows for retry. ItemProcessor and ItemWriter is retryable, but ItemReader is not retryable. The reason is because ItemReader is forward only logic and rolling back read transaction will be very difficult and thus retry does not apply to ItemReader.

You can see more how to configure retry here.

retry example from spring.io

You can set up custom RetryListener to log or do appropriate actions.

RetryListener interface doc from spring.io

Skip

Sometimes we will need to skip failures and continue to process the rest of the records. Spring Batch allows you to configure to skip based on specific exception and also how many items are valid to be skipped. You should probably not skipped all of the records, so the number of skipped item is a required attribute.

You can see more details for how to configure skip here.

skip example from spring.io

You can also set up custom SkipListeners to log the error or do appropriate actions.

SkipListener interface doc from spring.io