java.lang.Comparable

import java.util.Arrays;


public class MyInteger implements Comparable<Object>{
		private int n;
		public MyInteger(int n) {
		this.n = n;
	}
		
	public int compareTo(Object o) {
		if (o instanceof MyInteger){
		   MyInteger mi = (MyInteger)o;
		   if (mi.n == this.n){
		    return 0;
		   }
		   else if (mi.n > this.n){
		    return 1;
		   }
		   else {
		    return -1;
		   }
		}
		else {
		   return -1;
		}
	}
	
	public static void main(String[] args) {
		int n = 10;
		MyInteger []mis = new MyInteger[n];
		for (int i = 0;i < mis.length; i++){
		   mis[i] = new MyInteger((int)(Math.random() * 100));
		}
		for (MyInteger m:mis){
		   System.out.print(m.n + "\t");
		}
		Arrays.sort(mis);
		System.out.println();
		for (MyInteger m:mis){
		   System.out.print(m.n + "\t");
		}
	}
}

import java.util.*;
public class EmployeeSortTest {

	
	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 ，  Comparable 
		
		for(Employee e: staff)
		System.out.println("id=" + e.getId() + " name=" + e.getName() +
		".salary=" + e.getSalary());
	}
	
}
	
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(salary < other.salary)//  sort 
		return -1;
		if(salary > other.salary)
		return 1;
		return 0;
	}
	private int id;
	private String name;
	private double salary;
}