方法的概念理解和demo

package com.example.yan.java方法;
public class MehtodDemo01 {
    public static void main(String[] args) {
        stee();
        stringName("yan");
        int d = leeDeo(7);
        System.out.println(d);
    }
    public static void stee() {
        System.out.println("My name is long");
    }
    public static void stringName(String name) {
        System.out.println("My name is>" + name);
    }
    public static int leeDeo(int i) {
        return i;
    }
}

My name is long
My name is>yan
7

package com.example.yan.java方法;
public class MehtodDemo02 {
    public static void main(String[] args) {
        System.out.println(dueLl());
        System.out.println(dueLl(1));
        System.out.println(dueLl(1, 2));
        System.out.println(dueLl(1, 2, 23));
        System.out.println(dueLl(new int[]{1, 2, 3, 4, 5, 6, 7}));
    }
    public static int dueLl(int... ll) {
        int s = 0;
        for (int nums : ll) {
            s += nums;
        }
        return s;
    }
}

0
1
3
26
28

package com.example.yan.java方法;
public class MehtodDemo03 {
    public static void main(String[] args) {
        System.out.println(Namess("闫文超"));
        System.out.println(Namess("闫文超","16"));
        System.out.println(Namess("闫文超","18","未来可以更好"));
    }
    public static String Namess(String name){
        return name;
    }
    public static String Namess(String name,String age){
        return name+age;
    }
    public static String Namess(String name,String age,String love){
        return name+"年龄"+age+"喜欢"+love;
    }
}

闫文超
闫文超16
闫文超年龄18喜欢未来可以更好

package com.example.yan.java方法;
import static com.example.yan.java方法.MainClass3.fibonacci;
import static com.example.yan.java方法.MainClass4.factorial;
public class MehtodDemo04 {
    public static void main(String[] args) {
        System.out.println(lle(5));
        System.out.println(llel(8));
    }
    //递归阶乘
    public static long lle(int n) {
        if (n == 1) {
            return 1;
        }
        return n * factorial(n - 1);
    }
    //菲波那切数列
    //1,1,2,3,5,8,13,21,34    后面一个数等于前2位数相加
    //递归阶乘
    //本人暂时存疑问
    //f(1)=1 f(2)=1 f(x)=f(x-1)+f(x-2);
    public static long llel(int n) {
        if (n == 1 || n==2) {
            return 1;
        }
        return fibonacci(n - 1)+fibonacci(n - 2);
    }
}

120
21