Among early German Jews Jacob Simon naming his son Simon Jacob was common before family names were used.  The family names were usually required by government edict.  I do not know how common continuing this practice with first name and middle name after a family name was adopted. Naming someone after a living father was not done by Eastern European Jews but maybe not for German Jews.  Based on a German Jewish family that I researched (they occupied my house in Pittsburgh around 1890) Jacob Kaufmann named a son Karl Jacob Kaufmann.  Karl Jacob named his son Karl Jacob Kaufmann Jr.  Other family members used Jr. 
Bob Malakoff
Pittsburgh PA