In my program I'm reading integers form console many times. Every time, I need to type this line.
new Scanner(System.in).nextInt();
I'm used to C/C++ and I'm wondering if I can define something like
#define READINT Scanner(System.in).nextInt();
and then, in every place in my java program I can read form console as
int a = new READINT;
But I read form books Java does not support macros.
Someone please explain me why is it so, and can I do this in any other way.
You can do this, for example, with Java Primitive Specializations Generator:
/* define READINT //
new Scanner(System.in).nextInt();
// enddefine */
...
int a = /* READINT */0/**/;
Macros are text-level pre-processing tools that can be badly abused if not carefully designed. Example:
#define MULTIPLY( a, b ) ( a * b )
MULTIPLE(1+2,3+4) will have the result of (1+2*3+4)
Another example
#define SQUARE( a ) ((a) * (a))
int x = 5;
SQUARE(x++);
will increment x twice. ((x++) * (x++))
I think that Java language designers did not buy it for these reasons, because it is meant to be simple.