Java: Converting ints & doubles to floats?

Question

Working on my assignment for Java and I have created a class called Triangle. This has 3 variables, side1, side2 and side3. My constructor method takes 3 float values and assigns them to each variable in turn.

My issue is if the user puts in (10,11.1,12.2) those are taken as (int,double,double) and not the float that I require (the assignment says the 3 sides must be float values).

So how can I convert each input into a float regardless of if it's an integer or double when inputted?

Thanks,

Jack.

• Michael K: How are you getting the input?
• Jack Franklin: At this stage I'm not getting input from the user, I have to manually enter it, and my assignment states the three values entered must be 10,11.1 and 12.2).

Answer 1

You will generally read the data in as the appropriate type -- e.g. Scanner.nextFloat. This will read "10" (or "11.1") as a float. To the compiler the only thing that matters is the type signatures.

Answer 2

Make your variable/parameters type Number. A number can be easily converted to any other numeric primitive type.

Number n1 = (int)1;
Number n2 = (double)123.456;
Float f1 = n1.floatValue();
Float f2 = n2.floatValue();

Answer 3

I'm assuming you're using literals which is causing the problem? Sticking an "f" after them will make them floats. Otherwise it's completely dependent on your user interface and how you're getting the values.

Answer 4

If you're accepting user input then you'll almost certainly be dealing with strings at the user level. If this is the case then you can use Float.valueOf(String) to get the float representation of a string.

You'll find the valueOf(String) static method on most, if not all, of the numeric types in Java for this kind of thing.