为什么将short转换为char是一个狭窄的转换？

为什么将short转换为char是一个狭窄的转换？

这是因为a

short

可以保持负值，而

char

您可能从中看不到

Character.MIN_VALUE

。让我举几个例子。

  short s = -124;  char c = 124; // OK, no compile time error  char d = -124; // NOT OK, compile time error since char cannot hold -ve values  char e = s; // NOT OK, compile time error since a short might have -ve values which char won't be able to hold  char f = (char)s; // OK, type casting. The negative number -124 gets converted to 65412 so that char can hold it  System.out.println((short)f); // -124, gets converted back to a number short can hold because short won't be able to hold 65412  System.out.println((int)f); // 65412, gets converted to 65412 because int can easily hold it.

A（负）号

-n

转换为时

char

，变得

2^16-n

。因此，

-124

成为

2^16-124 = 65412

我希望这有帮助。