To quote Bjarne Stroustrup, "Multiple inheritance is like a parachute. Most of the time you don't need it, but when you do need it, you really need it." ...

Java’s interface language feature confuses many Java newbies. Many mistakenly assume that interfaces only sidestep Java’s failure to support multiple implementation inheritance.

Java’s single inheritance limitation is usually not a problem in the normal course of development. In fact, the need to use multiple inheritance could be a sign of a bad design.