First declare the array, and then each object in the array must be instantiated separately.
public class Test {
public static void main(String[] args) {
Person[] ps = new Person[3]; // 声明一个对象数组,里面有三个对象
System.out.println("---------------数组声明后-------------------");
for (int x = 0; x < ps.length; x++) {
System.out.print(ps[x] + " "); // 循环输出
}
// 创建3个人,并实例化
Person p1 = new Person("jerry", 18);
Person p2 = new Person("tom", 20);
Person p3 = new Person("rose", 25);
ps[0] = p1; // 实例化第一个元素
ps[1] = p2; // 实例化第二个元素
ps[2] =p3; // 实例化第三个元素
System.out.println("\n---------------对象实例化-------------------");
for (int x = 0; x < ps.length; x++) {
System.out.print(ps[x] + " ");
}
}
}
class Person {
private String name; // 姓名属性
private int age; // 年龄属性
public Person(String name, int age) { // 通过构造方法设置内容
this.name = name; // 为姓名赋值
this.age = age; // 为年龄赋值
}
@Override
public String toString() {
return "Person [name=" + name + ", age=" + age + "]";
}
}
---------------数组声明后-------------------
null null null
---------------对象实例化-------------------
Person [name=jerry, age=18] Person [name=tom, age=20] Person [name=rose, age=25]
Attack No.: Micro Program School
https://www.jb51.net/article/168862.htm