2.Since the primitive holds the actual value and not a reference to an object, when you assign primitives you copy the contents from one place to another.
3.You must assign an objectto each reference before you use it, and if you try to use a reference that’s still null, the problem will be reported at run-time.
4.Whenever you manipulate an object, what you’re manipulating is the reference, so when you assign “from one objectto another” you’re actually copying a reference from one place to another.
