java: Comparable比较器，数组对象比较器

Arrays只适合一个数组/对象内的数值进行比较，

Comparable比较器（Compara）适合数组，对象，队列等排序，

Comparable是一个接口类，实现此接口必须复写：compareTo 方法，

compareTo方法会返回三个值：1,0，-1，可以利用这三个值进行排序

 

//比较器
class Student2 implements Comparable<Student2>{
	private int strno;
	private String name;
	private int age;
	private float score;
	
	
	
	public Student2(int strno, String name, int age, float score) {		
		this.strno = strno;
		this.name = name;
		this.age = age;
		this.score = score;
	}
	
	@Override
	public String toString() {
		// TODO 自动生成的方法存根
		return "学号："+this.strno+",姓名："+this.name+",年龄："+this.age+",成绩："+this.score;
	}
	@Override
	public int compareTo(Student2 stu) {
		// TODO 自动生成的方法存根
		if(this.score > stu.score)
		{
			return 1;
		}else if(this.score < stu.score){
			return -1;
		}else{
			return 0;
		}
	}
	
	
}


public class CompareDemo {

	public static void main(String args[])
	{
		Student2 stu[] = {new Student2(1,"张三",20,98.13f),
				new Student2(2,"李四",33,88.18f),
				new Student2(3,"王五",41,80.32f),
				new Student2(4,"赵六",28,89.77f),
				new Student2(5,"田七",25,90.53f)};
		
		//排序
				System.out.println("++++++++++++数组排序前+++++++++++++++");
				print(stu);
				System.out.println("++++++++++++数组排序后+++++++++++++++");
				Arrays.sort(stu);
				print(stu);
	}
	
	public static void print(Student2 stu[])
	{
		for(int i=0;i<stu.length; i++)
		{
			
			System.out.println(stu[i]);
		}
	}
	
}