multi-line construction.

[ischuldt]

So it's been awhile for me on java, I've been stuck in c++ for awhile, but i'm trying to remember how java would naturally solve this.

so lets say i have class called City with a getter that returns the name of the city in string form.

I can initialize that by saying

City my_city = new City("New York");
system.out(my_city.name());

If I remember correctly though I can also do it this way..

City my_city;
my_city = new City("New York");
system.out(my_city.name());

but what would happen if I did this...?

City my_city;
system.out(my_city.name());

would an error get thrown or would it just print a blank string?

[sunde887]

A null pointer exception will get thrown when you attempt to call a method on an uninitialized object reference.

[Skiller]

You'd get an error because my_city has not been initialized.

[ischuldt]

ok so what if I did this...

State my_state;
//my_state = new State("NY");

City my_city;
my_city = new City(my_state, "New York");

can I assume the initialization of the new City would also throw that error since state isn't initialized?

Also would that be a run time or a compile time error?

[kjkrum]

It would be a compile-time warning and a run-time error.