传递给需要对象类型的方法时，整数变为长整数

Question

public class Main
{
    public static void main(String args[])
    {
        process(true ? 1 : 2L);
    }


    static void process(Object object)
    {
        System.out.println(object instanceof Integer);
    }
}

My expected output is true .

But actual out put is false .

My understanding is between integral data types the largest type will be assigned. If so what is this called?

Answer 1

The then and else parts of true ? 1 : 2l true ? 1 : 2l are int and long . The result is the widest, long , the the then-part is cast to long. See JLS .

In Computer Science a term for this is balancing types .

34 / 2.0        // double, more a case of _widening a type_.
c ? 2.0 : 34    // double

Answer 2

像指出这里，具有三元表达式int和long将经受二进制数字转换，从而导致long 。