关于实现Comparable接口的一个小程序

import java.util.*;
public class EmployeeSortTest {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Employee[] staff = new Employee[3];
		staff[0] = new Employee("harry Hacker",35000);
		staff[1] = new Employee("carl cracke",75000);
		staff[2] = new Employee("tony Tester",38000);

		Arrays.sort(staff);//sort方法可以实现对对象数组排序，但是必须实现                 Comparable接口
		                   /*Comparable接口原型为：
		                    * public interface Comparable<T>
		                    * {
  		                    *      int compareTo（T other);//接口的中方法自动属于public方法
		                    * }
		                    */
		for(Employee e: staff)
			System.out.println("id="+e.getId()+"  name="+e.getName()+
					".salary="+e.getSalary());
	}

}
/*
 * 因为要实现对Employee对象的排序，所以在Employee类中要实现Comparable接口，
 * 也就是要实现comepareTo()方法
 */
class Employee implements Comparable<Employee>
{
	public Employee(String n,double s)
	{
		name = n;
		salary = s;
		Random ID = new Random();
		id = ID.nextInt(10000000);
	}
	public int getId()
	{
		return id;
	}
	public String getName()
	{
		return name;
	}

	public double getSalary()
	{
		return salary;
	}

	public void raiseSalary(double byPercent)
	{
		double raise  = salary *byPercent/100;
		salary+=raise;
	}

	public int compareTo(Employee other)
	{
		if(id<other.id)//这里比较的是什么 sort方法实现的就是按照此比较的东西从小到大排列
			return -1;
		if(id>other.id)
			return 1;
		return 0;
	}
	private int id;
	private String name;
	private double salary;
}

在JDK5.0中Comparable接口，已经改进为泛型接口，这点我觉得非常好就少了那种比较看着人不爽的类型转换了
例如：

class Employee implements Comparable
{
.
.
.
.
.
public int compareTo(object otherobject)
{
Employee other = (Employee)otherobject//手动转换所需要的类型
if(id<other.id)
return -1;
if(id>other.id)
return 1;
return 0;
}
.
.
.
.
.
.
}

[/code][code="java"]