Hanging out with my dog at Guadalupe Park near little italy. There is a person sitting in the shade near the water fountain that I noticed as a get my dog some water. My dog and I are playing fetch in the middle of the field for about 20 minutes. This dude (5'7-5'9", mid to late 30s?, Hispanic, 200+lbs) who was sitting at the fountain comes walking up sort of a pissed off look in his face but I'm trying not to judge, maybe it's just his rbf I don't know. I assume he going to ask me for money or about my dog so I just say "hey, how's it going?". About 2-3 arms length away he quickly closes the distance and starts punching me in the face, no warning or cussing just 3 quick jabs to my face. I immediately start covering my face and turning away while running, being hit in the back of the head while doing so. 4-5 punches later he walks back to his stuff and starts walking towards the sap center. I call the cops and report it. I'm physically okay, slight black eye and a cut below above my eye, light bruising and soreness around my chin and back of head. Mentally pissed that this sort of behavior probably will go without justice or penalty. And mad at myself for being too trusting and unprepared for the situation. Just venting my San jose frustrations. I moved here 3 years ago from Michigan.