【Example1 】描述显式声明和隐式声明的区别用法

package com.tingle.j2se.basic;

/**
 * Created on 2020/4/20 17:28
 *
 * 本节主要描述显式声明和隐式声明的区别用法
 * @author Tingle
 */
public class Example1 {

    private static String a;
    private static String b = null;
    private static String c = "";
    private static String d = "iTingle";

    private static void test1(){
        System.out.println(a);    //输出 null(如果未用static 修饰，则会报错)，声明默认初始化未null对象
        System.out.println(b);    //输出 null
        System.out.println(c);    //输出空字符串
        System.out.println(d);    //输出  iTingle
    }

    public static void main(String[] args) {
        test1();
    }
}