为什么构造函数中不调用短数据类型[重复]

Question

public class Overloaded {

    Overloaded(byte i) {
        System.out.println(" con 1 is  called ");
    }

    Overloaded(short j) {

        System.out.println(" con 2 is  called ");
    }

    /*
     * Overloaded(int n) {
     * 
     * 
     * System.out.println(" con 3 is  called ");
     * 
     * 
     * }
     */

    /*
     * Overloaded(long m) {
     * 
     * System.out.println(" con  4 is  called ");
     * 
     * 
     * }
     */

    /*
     * Overloaded(float m) {
     * 
     * System.out.println(" con  5 is  called ");
     * 
     * 
     * }
     */

    public static void main(String[] t) {
        Overloaded o = new Overloaded(127);
    }
}

错误：可能有损转换从int到短

Answer 1

上面的代码不会产生错误。它宁愿显示一个输出- con 3被调用。短类型可以在构造函数中调用。将其类型转换为short

Overloaded o = new Overloaded((short)127);

Answer 2

默认情况下，所有数值常量都是整数类型，当您想要将整数保存到字节/短整型字段时，您需要使用cast进行收缩转换:

(byte)127
(short)127

或者你的情况是:

Overloaded o = new Overloaded((byte)127);

或者如果你想做空：

Overloaded o = new Overloaded((short)127);

Answer 3

表达式127不是short-而是 类型。

如果要具有 short 类型的表达式，请使用（short） 127，如：

Overloaded o = new Overloaded((short)127);

那么你的例子就会起作用。