public class Person {private int age ;private String name ;private Book book ;//一个人有一个书private Person child ;//一个人有一个孩纸public Person(int age, String name) { //构造函数super();this.age = age;this.name = name;}public int getAge() {return age;}public void setAge(int age) {this.age = age;}public String getName() {return name;}public void setName(String name) {this.name = name;}public Book getBook() {return book;}public void setBook(Book book) {this.book = book;}public Person getChild() {return child;}public void setChild(Person child) {this.child = child;}
}

public class Book {private String title ;private double price ;private Person person ; //一本书属于一个人public Book(String title, double price) {super();this.title = title;this.price = price;}public String getTitle() {return title;}public void setTitle(String title) {this.title = title;}public double getPrice() {return price;}public void setPrice(double price) {this.price = price;}public Person getPerson() {return person;}public void setPerson(Person person) {this.person = person;}
}

public class RefTest {/*** @param args* 对象之间的引用传递*/public static void main(String[] args) {// TODO Auto-generated method stubPerson per = new Person(30,"张三") ;Person cld = new Person(10,"张草") ;Book bk = new Book("JAVA开发实战经典",30.3) ;Book b = new Book("一千零一夜",10.3) ;per.setBook(bk) ;//设置两个对象之间的关系,一个人拥有一本书bk.setPerson(per) ;//设置两个对象之间的关系,一本书属于一个人cld.setBook(b) ; //一个孩纸有一本书b.setPerson(cld) ;//一个书属于一个孩纸per.setChild(cld) ;//一个人有一个孩子System.out.println("从人找到书————————>姓名:"+per.getName()+",年龄:"+per.getAge()+",书名:"+per.getBook().getTitle()+",价格:"+per.getBook().getPrice());System.out.println("从书找到人————————>书名："+bk.getTitle()+",价格:"+bk.getPrice()+",姓名:"+bk.getPerson().getName()+",年龄:"+bk.getPerson().getName());//通过人找到孩纸，并找到孩纸拥有的书System.out.println(per.getName()+"的孩纸————>姓名:"+per.getChild().getName()+",年龄:"+per.getChild().getAge()+",书名:"+per.getChild().getBook().getTitle()+",价格:"+per.getChild().getBook().getPrice());}}