《用java程式設計》：定義一個Employee類，屬性name：String；age：int；salary：double；把若干Employee物件放入List中，排序並遍歷；排序規則：salary高則在前面，salary相同時age大則在前面，age相同時按照name升序排列。

public class Employee implements Comparable{

	private String name;
	private int age;
	private double sarlay;
	
	public Employee(){}
	public Employee(String name,int age,double sarlay){
		this.name=name;
		this.age=age;
		this.sarlay=sarlay;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}
	public double getSarlay() {
		return sarlay;
	}
	public void setSarlay(double sarlay) {
		this.sarlay = sarlay;
	}
	@Override
	public int compareTo(Object o) {
		Employee emp=(Employee)o;
		
		if(this.sarlay!=emp.sarlay){
			return (int)(this.sarlay-emp.sarlay);
		}
		
		if(this.age!=emp.age){
			return this.age-emp.age;
		}
		return this.name.compareTo(emp.name);
	}

}

/ 排序
int a = list.size();
 

System.out.println(a);
for (int j = 0; j < list.size(); j++) {
for (int i = 0; i < list.size()-1-j; i++) {
Employee emp1 = (Employee) list.get(i);
Employee emp2 = (Employee) list.get(i+1);
if(emp1.getSalary() < emp2.getSalary()){
list.set(i, emp2);
list.set(i+1, emp1);
}else if(emp1.getSalary() == emp2.getSalary()){
if(emp1.getAge() < emp2.getAge()){
list.set(i, emp2);
list.set(i+1, emp1);
}else if(emp1.getAge() == emp2.getAge()){
if(emp1.getName().compareTo(emp2.getName()) >0){
list.set(i, emp2);
list.set(i+1, emp1);
}
}
}
}
}


// 遍歷
Iterator it = list.iterator();


while (it.hasNext()) {
Employee emp = (Employee) it.next();


System.out.print(emp.getName() + "\t");
System.out.print(emp.getAge() + "\t");
System.out.print(emp.getSalary() + "\n");


}
}


}
}