How to multiply 10 to an "Integer" object in Java?

Question

How do I multiply 10 to an Integer object and get back the Integer object?

I am looking for the neatest way of doing this.

I would probably do it this way: Get int from Integer object, multiply it with the other int and create another Integer object with this int value.

Code will be something like ...

integerObj = new Integer(integerObj.intValue() * 10);

But, I saw a code where the author is doing it this way: Get the String from the Integer object, concatenate "0" at the end and then get Integer object back by using Integer.parseInt

The code is something like this:

String s = integerObj + "0";
integerObj = Integer.parseInt(s);

Is there any merit in doing it either way?

And what would be the most efficient/neatest way in general and in this case?

Answer 1

With Java 5's autoboxing, you can simply do:

Integer a = new Integer(2); // or even just Integer a = 2;
a *= 10;
System.out.println(a);