Employee;
package textq; /** * 调用接口Comparable排序 * @author Administrator * */ public class Employee implements Comparable<Employee>{ private int id; private String name; private int age; public Employee(int id,String name,int age){ this.id=id; this.name=name; this.age=age; } @Override //利用编号实现排序 public int compareTo(Employee o){ if(id>o.id) return 1; else return -1; } @Override public String toString(){ StringBuilder sb=new StringBuilder(); sb.append("员工编号"+id+","); sb.append("员工的名字"+name+","); sb.append("员工的年龄"+age); return sb.toString(); } }
Test:
package textq; import java.util.ArrayList; import java.util.Collections; import java.util.List; public class Test { public static void main(String[] args) { List<Employee> list=new ArrayList<Employee>(); list.add(new Employee(3,"java",21)); list.add(new Employee(2,"java",22)); list.add(new Employee(1,"java",23)); System.out.println("排序前"); for(Employee employee:list){ System.out.println(employee); } System.out.println("排序后"); Collections.sort(list); for(Employee employee:list){ System.out.println(employee); } } }