欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识!
您现在的位置是: 首页  >  IT编程

如何基于Java实现对象List排序

程序员文章站 2023-01-25 18:58:29
这篇文章主要介绍了如何基于java实现对象list排序,文中通过示例代码介绍的非常详细,对大家的学习或者工作具有一定的参考学习价值,需要的朋友可以参考下 按照对象中的某个属性,对对象...

这篇文章主要介绍了如何基于java实现对象list排序,文中通过示例代码介绍的非常详细,对大家的学习或者工作具有一定的参考学习价值,需要的朋友可以参考下

按照对象中的某个属性,对对象list进行排序。

以初唐四杰的成绩排名为例,对诗人进行排序。

java实现如下:

1、诗人(poet)类结构,定义如下:

/**
 * created by miracle luna on 2020/1/11
 */
public class poet {
  private string name;
  private double score;

  public poet(string name, double score) {
    this.name = name;
    this.score = score;
  }

  public string getname() {
    return name;
  }

  public void setname(string name) {
    this.name = name;
  }

  public double getscore() {
    return score;
  }

  public void setscore(double score) {
    this.score = score;
  }

  @override
  public string tostring() {
    return "poet{" +
        "name='" + name + '\'' +
        ", score=" + score +
        '}';
  }
}

2、诗人按照成绩排名,代码如下:

import java.util.arraylist;
import java.util.comparator;
import java.util.list;

/**
 * created by miracle luna on 2020/1/11
 */
public class poetsort {

  public static void main(string[] args) {
    list<poet> poetlist = new arraylist<poet>();
    poet poet1 = new poet("杨炯", 94.0);
    poetlist.add(poet1);
    poet poet2 = new poet("卢照邻", 92.5);
    poetlist.add(poet2);
    poet poet3 = new poet("骆宾王", 95.0);
    poetlist.add(poet3);
    poet poet4 = new poet("王勃", 99.5);
    poetlist.add(poet4);


    // 初始顺序
    system.out.println("==> 初始顺序如下:");
    poetlist.foreach(poet -> system.out.println(poet.tostring()));

    // 按照分数排名(从高到低)
    poetlist.sort(new comparator<poet>() {
      @override
      public int compare(poet poet1, poet poet2) {
        double score1 = poet1.getscore();
        double score2 = poet2.getscore();
        return score2.compareto(score1);
      }
    });
    system.out.println("\n==> 按照分数排名(从高到低)如下:");
    poetlist.foreach(poet -> system.out.println(poet.tostring()));

    // 按照分数排名(从低到高)
    poetlist.sort(new comparator<poet>() {
      @override
      public int compare(poet poet1, poet poet2) {
        double score1 = poet1.getscore();
        double score2 = poet2.getscore();
        return score1.compareto(score2);
      }
    });
    system.out.println("\n==> 按照分数排名(从低到高)如下:");
    poetlist.foreach(poet -> system.out.println(poet.tostring()));
  }
}

3、运行结果如下:

==> 初始顺序如下:
poet{name='杨炯', score=94.0}
poet{name='卢照邻', score=92.5}
poet{name='骆宾王', score=95.0}
poet{name='王勃', score=99.5}

==> 按照分数排名(从高到低)如下:
poet{name='王勃', score=99.5}
poet{name='骆宾王', score=95.0}
poet{name='杨炯', score=94.0}
poet{name='卢照邻', score=92.5}

==> 按照分数排名(从低到高)如下:
poet{name='卢照邻', score=92.5}
poet{name='杨炯', score=94.0}
poet{name='骆宾王', score=95.0}
poet{name='王勃', score=99.5}

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持。