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List集合對(duì)象中按照不同屬性大小排序的實(shí)例

更新時(shí)間：2017年03月06日 10:21:51 投稿：jingxian

下面小編就為大家?guī)?lái)一篇List集合對(duì)象中按照不同屬性大小排序的實(shí)例。小編覺(jué)得挺不錯(cuò)的，現(xiàn)在就分享給大家，也給大家做個(gè)參考。一起跟隨小編過(guò)來(lái)看看吧

實(shí)例如下：

package com.huad.luck;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

public class Test {
	public static void main(String[] args) {
		Person p = new Person();
		p.setName("tom");
		p.setAge(11);
		Person p1 = new Person();
		p1.setName("lilei");
		p1.setAge(19);
		Person p2 = new Person();
		p2.setName("json");
		p2.setAge(15);
		List<Person> list =new ArrayList<Person>();
		list.add(p);
		list.add(p1);
		list.add(p2);
		Collections.sort(list,new Comparator<Person>() {
			//這里可以再Person中實(shí)現(xiàn) Comparator<T>接口，重寫(xiě)compare方法
			@Override
			public int compare(Person o1, Person o2) {
				//這里按照名字排序
				 return o1.getName().compareTo(o2.getName()); 
				 //這里按照age排序
				 //return (o1.getAge()+"").compareTo(o2.getAge()+""); 
				 //。。。根據(jù)不同屬性值排序
			}  

		});
		for (int i = 0; i < list.size(); i++) {
			System.out.println(list.get(i).getName());
		}
	}
}
//Person類(lèi)
package com.huad.luck;

public class Person{
	private String name ;
	private int age;
	
	public Person(String name , int age) {
		this.name = name;
		this.age = age;
	}
	public Person( ) {
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}

}
<p style="padding-top: 0px; padding-bottom: 0px; margin-top: 8px; margin-bottom: 8px; line-height: 22.5px; letter-spacing: 0.5px; font-size: 12.5px; word-wrap: break-word; word-break: break-all; color: rgb(51, 51, 51); font-family: 'Microsoft YaHei', Verdana, sans-serif, 宋體;"><span style="padding: 0px; margin: 0px; letter-spacing: normal; font-stretch: normal; font-size: 14px; line-height: 24px; font-family: Tahoma; color: rgb(0, 0, 0);">用collection.sort（）方法對(duì)list集合排序</span><br style="padding: 0px; margin: 0px;" /></p><p style="padding-top: 0px; padding-bottom: 0px; margin-top: 0px; margin-bottom: 0px; line-height: 24px; font-size: 14px; word-wrap: break-word; word-break: break-all; font-stretch: normal; font-family: Tahoma;"><span style="padding: 0px; margin: 0px; list-style: none outside none; word-wrap: break-word; word-break: normal;"><span style="padding: 0px; margin: 0px; list-style: none outside none; line-height: 21px; word-wrap: break-word; word-break: normal;"></span></span></p><p style="padding-top: 0px; padding-bottom: 0px; margin-top: 1em; margin-bottom: 0.5em; line-height: 24px; font-size: 14px; word-wrap: break-word; word-break: break-all; font-stretch: normal; font-family: Tahoma;">第一種是list中的對(duì)象實(shí)現(xiàn)Comparable接口，如下：<span style="padding: 0px; margin: 0px; list-style: none outside none; word-wrap: break-word; word-break: normal;"> </span></p><pre class="java" style="padding: 5px; margin-top: 0px; margin-bottom: 0px; line-height: 18px; font-size: 9pt; font-family: 'Courier New', Arial; border: 1px solid rgb(221, 221, 221); color: rgb(51, 51, 51); background: rgb(246, 246, 246);">/** 
* 根據(jù)order對(duì)User排序 
*/ 
public class User implements Comparable<User>{ 
  private String name; 
  private Integer order; 
  public String getName() { 
    return name; 
  } 
  public void setName(String name) { 
    this.name = name; 
  } 
  public Integer getOrder() { 
    return order; 
  } 
  public void setOrder(Integer order) { 
    this.order = order; 
  } 
  public int compareTo(User arg0) { 
    return this.getOrder().compareTo(arg0.getOrder()); 
  } 
}

測(cè)試一下：

public class Test{
  public static void main(String[] args) { 
    User user1 = new User(); 
    user1.setName("a"); 
    user1.setOrder(1); 
    User user2 = new User(); 
    user2.setName("b"); 
    user2.setOrder(2); 
    List<User> list = new ArrayList<User>(); 
    //此處add user2再add user1 
    list.add(user2); 
    list.add(user1); 
    Collections.sort(list); 
    for(User u : list){ 
      System.out.println(u.getName()); 
    } 
  } 
}

輸出結(jié)果如下

a
b

第二種方法是根據(jù)Collections.sort重載方法來(lái)實(shí)現(xiàn)，例如：

/** 
* 根據(jù)order對(duì)User排序 
*/ 
public class User { //此處無(wú)需實(shí)現(xiàn)Comparable接口 
  private String name; 
  private Integer order; 
  public String getName() { 
    return name; 
  } 
  public void setName(String name) { 
    this.name = name; 
  } 
  public Integer getOrder() { 
    return order; 
  } 
  public void setOrder(Integer order) { 
    this.order = order; 
  } 
}

主類(lèi)中這樣寫(xiě)即可：

public class Test{ 
  public static void main(String[] args) { 
    User user1 = new User(); 
    user1.setName("a"); 
    user1.setOrder(1); 
    User user2 = new User(); 
    user2.setName("b"); 
    user2.setOrder(2); 
    List<User> list = new ArrayList<User>(); 
    list.add(user2); 
    list.add(user1); 
    
    Collections.sort(list,new Comparator<User>(){ 
      public int compare(User arg0, User arg1) { 
        return arg0.getOrder().compareTo(arg1.getOrder()); 
      } 
    }); 
    for(User u : list){ 
      System.out.println(u.getName()); 
    } 
  } 
}

輸出結(jié)果如下

a
b

前者代碼結(jié)構(gòu)簡(jiǎn)單，但是只能根據(jù)固定的屬性排序，后者靈活，可以臨時(shí)指定排序項(xiàng)，但是代碼不夠簡(jiǎn)潔

多字段的場(chǎng)合：

Collections.sort(list,new Comparator<User>(){ 

public int compare(User arg0, User arg1) { 

// 第一次比較專(zhuān)業(yè) 

int i = arg0.getOrder().compareTo(arg1.getOrder());

// 如果專(zhuān)業(yè)相同則進(jìn)行第二次比較 

if(i==0){ 

// 第二次比較 

int j=arg0.getXXX().compareTo(arg1.getXXX()); 

// 如果學(xué)制相同則返回按年齡排序 

if(j==0){ 

return arg0.getCCC().compareTo(arg1.getCCC()); 

} 

return j; 

} 

return i; 

} 

});

以下是另外一個(gè)例子

package test;

import java.util.ArrayList; 

import java.util.Collections; 

import java.util.Comparator;

public class ArrayListTest { 

public static void main(String[] args) { 

ArrayList<Exmployee> arrayList = new ArrayList<Exmployee>() ; 

arrayList.add(new Exmployee("zengqiang",new Integer(5000))) ; 

arrayList.add(new Exmployee("zengmin",new Integer(4000))) ; 

arrayList.add(new Exmployee("liuxiaojuan",new Integer(4200))) ; 

arrayList.add(new Exmployee("giuming",new Integer(2200))) ; 

Collections.sort(arrayList, new Comparator<Exmployee>(){ 

public int compare(Exmployee arg0, Exmployee arg1) { 

return arg1.getSalary()-arg0.getSalary() ; //按照工資升序 

//return arg0.getSalary()-arg1.getSalary() ; 按照工資降序 

//return arg0.getName().compareTo(arg1.getName()) ; 按照姓名升序 

} 

}); 

for(Exmployee e:arrayList) 

System.out.println(e.getName()+"'s salary is "+e.getSalary()) ; 

}

}

class Exmployee { 

public Exmployee(String name, int salary) { 

this.name = name ; 

this.salary = salary ; 

}

private String name;

public String getName() { 

return name; 

}

public void setName(String name) { 

this.name = name; 

}

public int getSalary() { 

return salary; 

}

public void setSalary(int salary) { 

this.salary = salary; 

}

private int salary; 

}

以上這篇List集合對(duì)象中按照不同屬性大小排序的實(shí)例就是小編分享給大家的全部?jī)?nèi)容了，希望能給大家一個(gè)參考，也希望大家多多支持腳本之家。

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