题解 | #定义打印方法#

import java.util.Scanner;

public class Main {

public static void main(String[] args) throws Exception//方法可能抛出异常的声明 {
    Scanner scanner = new Scanner(System.in);
    while (scanner.hasNext()) {
        String className = scanner.next();
        // print就是需要你定义的方法
        print(Class.forName(className).newInstance());//newInstance:弱类型，低效率，只能用于无参构造；new：强类型，高效率，能调用任何public构造；Class.forName()为获取类型的方法
    }
}

//write your code here......
private static void print (Object obj){//static不能缺少
    System.out.print(obj.getClass().getName());//获取类名
}

}

class First { public String toString() { return "First"; } }

class Second { public String toString() { return "Second"; } }

class Third { public String toString() { return "Third"; } }