I have one here for about 15 years. I never thought of it as messy, but it is such a rampant grower, it needs pruning to keep it within reach. It is a very stiff upright grower and I am not sure it is a good candidate for training over a walkway. Al

If you time your pruning to be soon after bloom, as the fruit forms but before it falls, that will remove the fruit which causes the mess.

A neighbor has some as small trees, they look quite nice. I believe he prunes more than once a year. The mature size is listed at 30 feet or so, which means that it will keep trying to get to 30 feet or so. Something to think about. Being native to China/Japan/Korea it will expect more water than some of California gets, so if you are in a drier area it's probably going to be slower.

Thanks for your responses, seems like it is too big for the spot, so I dug it up and put it in a pot .