程序不报错，但是无法执行

Question

package test4;
import java.util.Scanner;

public class Hero{
private String name;
public int health;
private int grade;
public Hero() {
this.health=100;
this.grade=1;
System.out.println("请输入英雄的名字：");

Scanner scan=new Scanner(System.in);
this.name=scan.nextLine();
print();
}

public void print() {
System.out.println("Hero信息：");
System.out.println("姓名："+this.name);
System.out.println("生命值："+health);
System.out.println("等级："+grade);
System.out.println("----------------------------------------------------");
}
}

Answer 1

public Hero()是构造函数，只有刚声明一个Hero变量的时候才会执行，java程序运行都是从main函数开始的。

package test4;
import java.util.Scanner;

public class Hero{
  private String name;
  public int health;
  private int grade;
  public Hero() {
    this.health=100;
    this.grade=1;
    System.out.println("请输入英雄的名字：");

    Scanner scan=new Scanner(System.in);
    this.name=scan.nextLine();
    print();
  }

  public void print() {
    System.out.println("Hero信息：");
    System.out.println("姓名："+this.name);
    System.out.println("生命值："+health);
    System.out.println("等级："+grade);
    System.out.println("----------------------------------------------------");
  }

//缺少主函数
  public static void main(){
    Hero hero = new Hero();
  }
}

p.s.忘了主函数名的标准写法了，编译器会有提示的，函数体没问题。