下面小编就为大家带来一篇List集合对象中按照不同属性大小排序的实例。小编觉得挺不错的,现在就分享给大家,也给大家做个参考。一起跟随小编过来看看吧
实例如下:
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 list =new ArrayList(); list.add(p); list.add(p1); list.add(p2); Collections.sort(list,new Comparator() { //这里可以再Person中实现 Comparator接口,重写compare方法 @Override public int compare(Person o1, Person o2) { //这里按照名字排序 return o1.getName().compareto(o2.getName()); //这里按照age排序 //return (o1.getAge()+"").compareto(o2.getAge()+""); //。。。根据不同属性值排序 } }); for (int i = 0; i 用collection.sort()方法对list集合排序
第一种是list中的对象实现Comparable接口,如下:
/** * 根据order对User排序 */ public class User implements Comparable{ 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()); } }
测试一下:
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 list = new ArrayList(); //此处add user2再add user1 list.add(user2); list.add(user1); Collections.sort(list); for(User u : list){ System.out.println(u.getName()); } } }
输出结果如下
a
b
第二种方法是根据Collections.sort重载方法来实现,例如:
/** * 根据order对User排序 */ public class User { //此处无需实现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; } }主类中这样写即可: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 list = new ArrayList(); list.add(user2); list.add(user1); Collections.sort(list,new Comparator(){ public int compare(User arg0, User arg1) { return arg0.getorder().compareto(arg1.getorder()); } }); for(User u : list){ System.out.println(u.getName()); } } }输出结果如下ab前者代码结构简单,但是只能根据固定的属性排序,后者灵活,可以临时指定排序项,但是代码不够简洁多字段的场合:上一篇:Java获取磁盘空间的两种代码示例下一篇:SpringCloud URL重定向及转发代码实例 热门搜索:实例属性 实例对象 List集合 对象集合 集合排序