Why Hybris modelService.save() doesn't work inside the ifPresent() method?

Question

    private void doSomething(someProcessModel process){
        CustomerModel customer = process.getCustomerModel();

        customer.getFoos().stream()
                .filter(foo -> foo.getCountryCode().equals(process.getCountryCode()))
                .findFirst()
                .ifPresent(foo -> {
                    if(foo.getSomeNumber() == null){
                        foo.setSomeNumber("1234567");
                        modelService.save(foo);
                    }
                });
    }

As seen in the code snippet above, I have a 'CustomerModel' that has an attribute 'Foos'. It's a one-to-many relationship. As you can see I have done some filtering and in the end, I want to update the value of 'someNumber' attribute of 'Foo' if it is null. I've confirmed that everything is working as the "someNumber" attribute's value is updated during the debugging. It doesn't save at all as I have done my checking in the HMC. I have also validated that the Interceptor doesn't have any condition that would throw an error. There is nothing being shown in the log either.

I am wondering is it a legal approach to do the "modelService.save()' inside the 'ifPresent()' method? What could be the possible issue here?

Answer 1

I have found the root cause now as I have face the same issue again.

Context to my original question

To give more context to my original question, the #doSomething method resides in a Hybris Business Process action class and I have ended the action prematurely while I am debugging it (by stopping the debugging) once the #doSomething method is ran.

Root cause

The mentioned problem happened when I was debugging the action class. I assumed that the ModelService#save will persist the current state of the business process once it has been ran. However, the Hybris OOTB business process will do a rollback if there is any error (and I believe it was caused by me stopping the debugging half-way).

SAP Commerce Documentation:

All actions are performed inside their own transaction. This means that changes made inside the action bean run method are rolled back in case of an error.

Solution

Let the action runs completely!

Good to know

Based on the SAP Documentation and this blog post, there will be times that we will need to bypass a business process rollback even though there is an exception being thrown and there are ways to achieve that. More info can be found in this SAP Commerce Documentation and the mentioned blog post.

However, in some circumstances it may be required to let a business exception reach the outside but also commit the transaction and deal with the exception outside. Therefore, it is possible to make the task engine not roll back the changes made during a task which failed.