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From: =?UTF-8?Q?Arne_Vajh=c3=b8j?= <arne@vajhoej.dk>
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Subject: Re: Compare generics (that are numbers)
Date: Wed, 29 Jul 2020 13:21:56 -0400
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On 7/29/2020 11:19 AM, Cecil Westerhof wrote:
> I have a class that starts with:
>      abstract class CalcValuesGeneric<E> {
> 
> E will be Integer, int, Float or float. (For now, but always a Number.)
> What is the best way to determine which of the two is lower?

T extends Number?

Example:

public class NumFun {
	public static class Demo<T extends Number> {
		public boolean gt(T a, T b) {
			return a.doubleValue() > b.doubleValue();
		}
	}
	public static void main(String[] args) {
		Demo<Double> dd = new Demo<>();
		System.out.println(dd.gt(1.0, 0.0));
		System.out.println(dd.gt(1.0, 1.0));
		System.out.println(dd.gt(0.0, 1.0));
		Demo<Integer> di = new Demo<>();
		System.out.println(di.gt(1, 0));
		System.out.println(di.gt(1, 1));
		System.out.println(di.gt(0, 1));
	}
}

Arne