package list; public class Book implements Comparable{ String name; double price; public Book(String name, double price){ this.name = name; this.price = price; } @Override public int compareTo(Object o) { Book b=(Book) o; if(b.price==this.price){ return 1; }else{ return 0; } } }
package list; import java.util.ArrayList; import java.util.Iterator; public class Test { public static void main(String[] args) { ArrayList<Book> list = new ArrayList<Book>(); Book b1 =new Book("《Java基础》",200); Book b2 =new Book("《初级程序员》",220); Book b3 =new Book("《终极的自我修养》",222); Book b4 =new Book("《我是大boos》",2222); list.add(b1); list.add(b2); list.add(b4); list.add(b3); Book book=new Book("《模式匹配》",200); System.out.println("此书:"+book.name+"与以下书价格相同:"); Iterator<Book> it = list.iterator(); while(it.hasNext()) { Book b=it.next(); if(b.compareTo(book)==1){ System.out.println(b.name+"价格为"+book.price); } } } }