java比较器 之compareable 和comparato比较
compareable
测试类
import java.util.Set;
import java.util.TreeSet; public class Test { public static void main(String[] args) {
Set<Person>allset = new TreeSet<Person>();
allset.add(new Person(22,"hjw",20000.0,"论语",50.0));
allset.add(new Person(22,"fyy",7000.0,"大学",40.0));
allset.add(new Person(22,"hjl",6000.0,"孟子",30.0));
allset.add(new Person(22,"hlq",10000.0,"中庸",20.0));
allset.add(new Person(24, "hsx", 20000.0,"诗经", 40.0));
allset.add(new Person(22,"cl",20000.0,"离骚",10.0));
allset.add(new Person(22,"zsk",20000.0,"墨子",25.0));
allset.add(new Person(22,"hjw",20000.0,"论语",23.0));
allset.add(new Person(22,"hjw",20000.0,"论语",22.0));
System.out.println(allset);
} }
person类
public class Person extends Book implements Comparable<Person> {
private Integer age;
private String name;
private Double salary;
//private String book;
public Integer getAge() {
return age;
}
public Person(Integer age, String name, Double salary,String bookname, double price) {
super(bookname, price);
this.age = age;
this.name = name;
this.salary = salary;
//this.book = book;
}
public void setAge(Integer age) {
this.age = age;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Double getSalary() {
return salary;
}
public void setSalary(double salary) {
this.salary = salary;
}
@Override
public int compareTo(Person o) { if (this.salary>o.salary) {
return -1;
}
else if(this.salary<o.salary){
return 1;
}
else
{
if (this.age>o.age){
return 1;
}else if(this.age<o.age){
return -1;
}else{
if (this.name!=o.name) {
return this.name.compareTo(o.name);
}else {
if(this.price>o.price){
return 1;
}else if(this.price<o.price){
return -1;
}else {
return this.bookname.compareTo(o.bookname);
}
}
}
}
}
@Override
public String toString() {
return "Person [age=" + age + ", name=" + name + ", salary=" + salary + ", bookname=" + bookname + ", price="
+ price + "]";
} }
Book类
public class Book {
public String bookname;
public Double price; public Book(String bookname, double price) { this.bookname = bookname;
this.price = price;
}
public String getBookname() {
return bookname;
}
public void setBookname(String bookname) {
this.bookname = bookname;
}
public double getPrice() {
return price;
}
public void setPrice(double price) {
this.price = price;
}
@Override
public String toString() {
return "Book [bookname=" + bookname + ", price=" + price + "]";
} }
自定义比较器Comparator类
Book类
public class Book {
public String bookname;
public Double price;
public Book(){}
public Book(String bookname, double price) { this.bookname = bookname;
this.price = price;
}
public String getBookname() {
return bookname;
}
public void setBookname(String bookname) {
this.bookname = bookname;
}
public double getPrice() {
return price;
}
public void setPrice(double price) {
this.price = price;
}
@Override
public String toString() {
return "Book [bookname=" + bookname + ", price=" + price + "]";
} }
Person类
public class Person {
private Integer age;
private String name;
private double salary;
private Book book;
public Person(Integer age, String name, double salary,String bookname, double price) { this.age = age;
this.name = name;
this.salary = salary;
this.book=new Book(bookname,price); }
public Integer getAge() {return age;}
public void setAge(Integer age) {
this.age = age;
}
public Book getBook() {
return book;
}
public void setBook(Book book) {
this.book = book;
}
public void setSalary(double salary) {
this.salary = salary;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public double getSalary() {
return salary;
} @Override
public String toString() {
return "Person [age=" + age + ", name=" + name + ", salary=" + salary + ", book=" + book + "]";
} }
自定义Comparator类
import java.util.Comparator; public class SalaryCom implements Comparator<Person>{ @Override
public int compare(Person o1, Person o2) {
if(o1.getSalary()!=o2.getSalary()){
return (int) -(o1.getSalary()-o2.getSalary());
}else if(o1.getAge()!=o2.getAge()){
return (int) (o1.getAge()-o2.getAge());
}else if(o1.getName()!=o2.getName()){
return o1.getName().compareTo(o2.getName());}
else{
if(o1.getBook().price!=o2.getBook().price){
return (int) (o1.getBook().price-o2.getBook().price);
}else{
return o1.getBook().bookname.compareTo(o2.getBook().bookname);
} }
}
}
Test类
import java.util.Set;
import java.util.TreeSet;
public class Test { public static void main(String[] args) {
SalaryCom s =new SalaryCom();
Set<Person> allset = new TreeSet<Person>(s); allset.add(new Person(22,"hjw",20000,"论语",50.0));
allset.add(new Person(22,"fyy",7000,"大学",40.0));
allset.add(new Person(22,"hjl",6000,"孟子",30.0));
allset.add(new Person(22,"hlq",10000,"中庸",20.0));
allset.add(new Person(24,"hsx",20000,"诗经", 40.0));
allset.add(new Person(22,"cl",20000,"离骚",10.0));
allset.add(new Person(22,"zsk",20000,"墨子",25.0));
allset.add(new Person(22,"hj",20000,"论语",50.0));
allset.add(new Person(22,"hjw",20000,"论语",22.0));
System.out.println(allset);
} }
使用匿名内部类自定义比较器Comparator
Book类
public class Book {
public String bookname;
public Double price;
public Book(){}
public Book(String bookname, double price) {
this.bookname = bookname;
this.price = price;
}
public String getBookname() {
return bookname;
}
public void setBookname(String bookname) {
this.bookname = bookname;
}
public double getPrice() {
return price;
}
public void setPrice(double price) {
this.price = price;
}
@Override
public String toString() {
return "Book [bookname=" + bookname + ", price=" + price + "]";
}
}
Person类
public class Person {
private Integer age;
private String name;
private double salary;
private Book book;
public Person(Integer age, String name, double salary,String bookname, double price) { this.age = age;
this.name = name;
this.salary = salary;
this.book=new Book(bookname,price); }
public Integer getAge() {return age;}
public void setAge(Integer age) {
this.age = age;
}
public Book getBook() {
return book;
}
public void setBook(Book book) {
this.book = book;
}
public void setSalary(double salary) {
this.salary = salary;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public double getSalary() {
return salary;
} @Override
public String toString() {
return "Person [age=" + age + ", name=" + name + ", salary=" + salary + ", book=" + book + "]";
} }
Test测试类
import java.util.Comparator;
import java.util.Set;
import java.util.TreeSet; import com.qianfeng.homework02.Person; public class Test { public static void main(String[] args) {
Set<Person> allset = new TreeSet<Person>(new Comparator<Person>() { @Override
public int compare(Person o1, Person o2) {
if(o1.getSalary()!=o2.getSalary()){
return (int) -(o1.getSalary()-o2.getSalary());
}else if(o1.getAge()!=o2.getAge()){
return (int) (o1.getAge()-o2.getAge());
}else if(o1.getName()!=o2.getName()){
return o1.getName().compareTo(o2.getName());}
else{
if(o1.getBook().price!=o2.getBook().price){
return (int) (o1.getBook().price-o2.getBook().price);
}else{
return o1.getBook().bookname.compareTo(o2.getBook().bookname);
} }
}
}); allset.add(new Person(22,"hjw",20000,"论语",50.0));
allset.add(new Person(22,"fyy",7000,"大学",40.0));
allset.add(new Person(22,"hjl",6000,"孟子",30.0));
allset.add(new Person(22,"hlq",10000,"中庸",20.0));
allset.add(new Person(24,"hsx",20000,"诗经", 40.0));
allset.add(new Person(22,"cl",20000,"离骚",10.0));
allset.add(new Person(22,"zsk",20000,"墨子",25.0));
allset.add(new Person(22,"hj",20000,"论语",50.0));
allset.add(new Person(22,"hjw",20000,"论语",22.0));
System.out.println(allset.size());
System.out.println(allset); } }
注意：String 字符串类的Comparator已经实现了compareTo方法，可以直接进行调用比较！
java比较器 之compareable 和comparato比较的更多相关文章
- Java比较器对数组，集合排序一
数组排序非常简单,有前辈们的各种排序算法,再加上Java中强大的数组辅助类Arrays与集合辅助类Collections,使得排序变得非常简单,如果说结合比较器Comparator接口和Collato ...
- java比较器Comparable接口和Comaprator接口
Comparable故名思意是比较,意思就是做比较的,然后进行排序. 1.什么是comparable接口 此接口强行对实现它的每个类的对象进行整体排序.此排序被称为该类的自然排序 ,类的 compar ...
- 黑马----JAVA比较器：Comparable和Comparator
黑马程序员:Java培训.Android培训.iOS培训..Net培训 一.Comparable接口 1.public interface Comparable{ public int compare ...
- Java中equals与==和comparaTo的区别
一.先说说Java中equals和==的区别: Java中的数据类型,可分为两类: 1.基本数据类型(也叫原始数据类型) 八大基本数据类型 char byte short int long doubl ...
- java比较器Comparator 使用
PresonDemo package cn.stat.p5.person.demo; public class PresonDemo implements Comparable { private S ...
- Java比较器
导语 本节内容,比较器Comparable是核心内容. 主要内容 重新认识Arrays类 两种比较器的使用 具体内容 Arrays类 在之前一直使用的"java.util.Arrays.so ...
- Java 比较器
比较器 Arrays 类 主要功能: 完成所有与数组有关的操作的工具类 二分查找: 在一个有序的数字序列中进行二分查找 public static int binarySearch(数据类型 [] a ...
- TreeSet的两种实现方法:Comparable和Comparator（Java比较器）
Comparable与Comparator实际上是TreeSet集合的两种实现方式,用来实现对象的排序.下边介绍一下两种比较器的使用方法和区别. Comparable称为元素的自然顺序,或者叫做默认顺 ...
- 小白养成记——Java比较器Comparable和Comparator
一.使用情景 1. 调用Arrays.sort()方法或Collections.sort()方法对自定义类的对象排序 以Arrays.sort()为例.假定有如下自定义的Person类 1 publ ...
随机推荐
- 已知要闪回的大致时间使用基于as of scn的闪回查询
基本判断出要恢复误操作的dml的时间可以使用如下的方法进行数据的恢复: example: 一.创建test表 -------create table flashback_asof------ crea ...
- 在Struts2中使用poi进行excel操作下载的时候报getOutputStream() has already been called for this response 错误 [转]
在项目中用到了poi这个开源的操作excel文件的jar. 项目中用到struts2容器管理servlet.不是单纯的直接用servlet. workbook.write(os); ...
- python实现zabbix_sender的socket通信代码样例
sk = socket.socket() sk.connect(self.ip_port) sk.settimeout(5) sk.sendall(b'ZBXD\x01') sk.sendall(b' ...
- QT5删除隐藏目录+隐藏文件
1.功能需求 删除一个目录(包括目录本身),同时删除该目录中所有文件及目录(含隐藏的) 2.遇到的问题 qt5中已经有了递归删除目录的函数--->bool QDir::removeRecursi ...
- 构建混合云：配置Azure site to site VPN连接(1)
用户在构建自己云计算解决方案的时候,往往会选择私有云或者公有云来做部署,但在一些场景下,用户更加希望通过混合云的方案来满足自己的业务需求.Azure为混合云的部署提供多种不同的连接方案,最常见的是 ...
- Java Script 中 ==（Equal) 和 === (Identity Equal) 的区别和比较算法逻辑
判断两个变量是否相等在任何编程语言中都是非常重要的功能. JavaScript 提供了 == 和 === 两种判断两个变量是否相等的运算符,但我们开始学习的时候 JavaScript 的时候,就被一遍 ...
- C#多显示器转换的两种方法——SetWindowPos,Screen
原文 http://blog.csdn.net/hejialin666/article/details/6057551 实现多屏显示目的:一般情况下是一个电脑显示屏,外接一个电视显示屏.在电脑上显示的 ...
- ALLEN-XIE
ALLEN-XIE ABOUT Allen Xie是一家坚持理念至上的西装定制店.我们的价值观渗透于我们所做的每一件事中,从而确保始终遵循自己的风格.我们坚持用最高标准要求自己,因此,在制衣过程中 ...
- CURL常用命令---样例
原文地址: http://www.thegeekstuff.com/2012/04/curl-examples/ 下载单个文件,默认将输出打印到标准输出中(STDOUT)中 curl http://w ...
- ps 导出png-8图片会变模糊
出现这种情况的时候,在保存png-8图片的时候,索引色需要改为256,否则保存的图片颜色与原图会不一致.