java - 为什么int类型方法允许字符类型作为返回值？

Question

这个问题已经有答案了:

Converting Chars to Ints in Java (2 个回答)

已关闭 8 年前。

这是我的代码，但我不明白如何 int getValue()方法接受 char类型作为返回值。运作如何？有人可以解释一下这个方法是如何工作的吗？

public class CharToInteger {
    private static Scanner input;
    public static int getValue(char character){
        return character;       
    }

    public static void main(String[] args) {
        input = new Scanner(System.in);
        System.out.println("Enter a character to get value of it:");
        String inputString=(String) input.next();
        char inputCharacter=inputString.charAt(0);
        System.out.println(getValue(inputCharacter));
    }

}

提前致谢:)

Answer 1

public static int getValue(char character){
    return character;//<-- unicode value is being returned, e.g. char 0 -> int 48
    // char ranges from 0 - 65535
}

来自 JSL:

5.1.4. Widening and Narrowing Primitive Conversion

The following conversion combines both widening and narrowing primitive conversions:

byte to char

First, the byte is converted to an int via widening primitive conversion (§5.1.2), and then the resulting int is converted to a char by narrowing primitive conversion (§5.1.3).

see more :