Jaywalking is defined as crossing a street while not at an intersection or in a striped crosswalk, and this is not a simple question to answer.   In general, California law does not prohibit jaywalking unless you are between two signalized intersections.  https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?sectionNum=21955.&lawCode=VEH If so, you must use the signalized crossing.  

However, if jaywalking, pedestrians Do Not have right-of-way like they do in a legal crossing.  If jaywalking, pedestrians yield to passing vehicles, drivers do not have to yield to jaywalkers.   However, this difference with general belief can result in conflicting expectations and possibly a collision which will most likely be the worse for pedestrians, so jaywalking is not recommended.  

The big exception is local agency laws, since the California Vehicle Code allows local agencies to prohibit jaywalking.   These laws are typically enacted in high volume business districts or arterials with a history of pedestrian injury, so be sure to be informed of your local ordinances before considering jaywalking.