举一个简单的例子说明一下
需求: 通过关联两个类, 使可以通过 Person 对象获取所关联的 Car 类的对象中的数据
一个 Person 类, 一个 Car 类,
==> Person 类
- class Person{
- // 设置变量
- private int pid;
- private String pname;
- private int page;
- private Car carname;
- // 多参构造方法
- public Person(String pname, int page){
- this.setPname(pname);
- this.setPage(page);
- }
- public String getInfo(){
- return "姓名:" + getPname() + "\r" + "年龄:" + getPage() + "\r";
- }
- public void setCarName(Car carname){
- this.carname = carname;
- }
- public Car getCarName(){
- return this.carname;
- }
- public void setPname(String pname){
- this.pname = pname;
- }
- public String getPname(){
- return this.pname;
- }
- public void setPage(int page){
- this.page = page;
- }
- public int getPage(){
- return this.page;
- }
- }
==> Car 类
- class Car{
- private String cname;
- private Person pname;
- // 构造函数
- public Car(String cname){
- this.setCname(cname);
- }
- public void setPname(Person pname){
- this.pname = pname;
- }
- public Person getPname(){
- return this.pname;
- }
- public void setCname(String cname){
- this.cname = cname;
- }
- public String getCname(){
- return this.cname;
- }
- public String getCarInfo(){
- return "车名:" + getCname();
- }
- }
==> 测试类
- public class testDemo {
- public static void main(String[] args) {
- Person p = new Person("Tom", 20);
- Car car = new Car("宝马");
- p.setCarName(car);
- car.setPname(p);
- System.out.println(p.getInfo());
- // 通过 Person 对象获取 其 Car 对象中的内容
- System.out.println(p.getCarName().getCarInfo());
- // 通过 Car 对象获取 Person 对象中的内容
- System.out.println(car.getPname().getPname());
- }
- }
来源: http://www.bubuko.com/infodetail-2500643.html