public class StudentTest { private int id; private String name; int[] arr; public int[] getArr() { return arr; } public void setArr(int[] arr) { this.arr = arr; } public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; }}
public class guanxiaokun { public static void main(String[] args) { //对于javaBean对象的成员变量,都有默认值,如果成员变量是基本类型int 默认值为0,如果是引用类型,其默认值为null //数组对象,如果没有进行静态初始化,数组对象其每一个索引位置,如果是存储基本类型,默认值为0,如果存储引用类型,默认值就为null System.out.println(new StudentTest().getId());//0 System.out.println(new StudentTest().getName());//null System.out.println(new StudentTest().getArr());//null int[] arr = new int[3]; String[] str = new String[3]; System.out.println(arr[0]);//0 System.out.println(str[0]);//null }}
原文地址:https://www.cnblogs.com/gxk1314520jxx/p/10060651.html
时间: 2024-08-28 08:08:12