How to avoid null checking in Java?

Question

I use object != null a lot to avoid NullPointerException.

Is there a good alternative to this?

For example I often use:

Answer 1

The Google collections framework offers a good and elegant way to achieve the null check.

There is a method in a library class like this:

static  T checkNotNull(T e) {
   if (e == null) {
      throw new NullPointerException();
   }
   return e;
}

And the usage is (with import static):

...
void foo(int a, Person p) {
   if (checkNotNull(p).getAge() > a) {
      ...
   }
   else {
      ...
   }
}
...

Or in your example:

checkNotNull(someobject).doCalc();