This post is part of a series delving into the details of the JSR-352 (Java Batch) specification. Each post examines a very specific part of the specification and looks at how it works and how you might use it in a real batch application.To start at the beginning, follow the link to the first post.
The next post in the series is here
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WebSphere Liberty servers can be managed using the Admin Center which you can enable as a feature in the server. I won’t try to go into all the things you can do with it here, but the various features are grouped into “tools” which you can enable. One such tool is the Batch tool.
The Admin Center Batch tool is really an application that runs in your browser and uses the Liberty Batch REST API under the covers to provide function. What function is that? Well, it is essentially a web browser interface to look at (and manipulate) the Job Repository.
Using the REST interface under the covers the Admin Center Batch tool can fetch a list of jobs and display that list to you. Using the search capabilities we’ve discussed earlier, the tool can craft REST requests that filter or scope the resulting list to jobs that you are interested in. For example, you can see all the jobs submitted by a particular user or run after (or before) a certain date.
Once you have found the job you are interested in, you can select it and drill down to get more information. Again, the Batch tool is just using the REST API to fetch the details kept in the Job Repository about the job, but this allows you to see all the steps in the job and their status. Wondering how the third step in the job that ran yesterday turned out? The Batch tool lets you find that job and explore the step to see what happened.
We haven’t talked about Job Logs yet (we’ll get there) but the Batch tool can also fetch the log for a job and let you browse through it.
If you’re familiar with SDSF on z/OS then the Batch tool is providing similar function. It is an interface to let you see everything that has gone on and explore it in detail.
Well, ok, maybe not everything that has gone on. You will need to logon to allow the Batch tool to use the REST interface and your identity could limit what jobs you can see. Security is another topic we’ll get to eventually, but, as we’ve said before, the REST interface is secured so you can’t access jobs you aren’t authorized to and the Admin Center’s use of the REST interface inherits that security.
That’s all ‘read’ operations from the Admin Center. Next time we’ll look at ‘write’ operations..