Java中Infinity、-Infinity和NaN分别代表什么呢?

Infinity、-Infinity和NaN简介

Infinity:正无穷大
-Infinity:负无穷大
NaN:Not a Number

当float或double类型的数除零时
当被除数为非零值时,结果为无穷大
当被除数也为零值时,则结果为NaN

注意事项:
   浮点数做除法时除数可以为零值
    但整数类型会抛java.lang.ArithmeticException: / by zero异常

 
public class NaN {
	public static void main(String[] args) {
		System.out.println(1.0/0);
		System.out.println(-1.0/0.0);
		System.out.println(0.0/0.0);
		System.out.println("************************");
		double a = 1.0/0.0;//Infinity
		double b = 1.0/0.0;//Infinity
		double c = -0.0/0.0;//-Infinity
		double d = 0.0/0.0;//NaN
		double e = 0.0/0.0;//NaN
		System.out.println(a+10.0);//Infinity
		System.out.println(a == b);//true
		System.out.println(a == c);//false
		System.out.println(a == d);//false
		System.out.println(d == e);//false
	}
}

----运行以上代码，将输出以下信息----
Infinity
-Infinity
NaN
************************
Infinity
true
false
false
false