针对ArrayList中的某个属性进行排序

针对ArrayList中的某个属性进行排序

 

 

1.创建要比较的对象

   public class ExampleObj{ private Long prop; private String name; 

 public ExampleObj(Long prop,String name){      this.prop= prop;      this.name= name;   } public Long getProp() {     return prop; } public void setProp(Long prop) {  this.prop= prop; } public String getName() {  return name; } public void setName(String name) {  this.name = name; }}

 

2.实现java.util.Comparator<T>接口

 

import java.io.Serializable;import java.util.Comparator;

public class ComparatorExampleObj implements Comparator<ExampleObj>,Serializable { public int compare(ExampleObj o1, ExampleObj o2) {  ExampleObj p1 = (ExampleObj) o1;  ExampleObj p2 = (ExampleObj) o2;  //按升序排列  if (p1.getProp() > p2.getProp())   return 1;  else   return 0; }}

3.排序

ArrayList list = new ArrayList();  list.add(new ExampleObj (1,"name1"));  list.add(new ExampleObj (3,"name3"));  list.add(new ExampleObj (2,"name2"));

 

ComparatorExampleObj comp = new ComparatorExampleObj ();  Collections.sort(list,comp); 

//此时list为以按prop属性进行过升序排序的集合类

 

 

相关资源：敏捷开发V1.0.pptx