new对象构造函数执行顺序

/**
 *
 */
package oj.test;

/**
 * @author jWX194406
 *
 */
public class Recursion
{
    static int sum = 0;
   
    public static int recursionSum(int num)
    {
        sum += num;
        if (num > 0)
        {
            recursionSum(num - 1);
        }
        return sum;
    }
   
    public int recursion(int num)
    {
        int sum = 0;
        if (num > 0)
        {
            sum = num + recursion(num - 1);
        }
        return sum;
    }

    public static void main(String[] args)
    {
        System.out.println(recursionSum(100));
        Recursion recursion = new Recursion();
        System.out.println(recursion.recursion(100));
        /**
         * new Child("mike");
         * 的执行顺序：
         * 父类People的People()构造函数最先执行，然后是Child类的public Child(String name)构造函数，
         * public Child(String name)构造函数里People father = new People(name + ":F");
         * 调用父类People的public People(String name)构造函数。
         */
        new Child("mike");
    }
}

class People
{
    String name;
   
    public People()
    {
        System.out.print(1);
    }
   
    public People(String name)
    {
        System.out.print(2);
        this.name = name;
    }
}

class Child extends People
{
    //People father;
    public Child(String name)
    {
        System.out.print(3);
        this.name = name;
        People father = new People(name + ":F");
    }
   
    public Child()
    {
        System.out.print(4);
    }
}