Java线程练习3-6，烦请老师检查并指正～

Letter类
​
​package com.imooc.thread.exercise3_6;

public class Letter implements Runnable {
	char[] arr = new char[26];

	public Letter() {
		for (int i = 0; i < arr.length; i++) {
			arr[i] = (char) ('a' + i);
		}
	}

	@Override
	public void run() {
		for (int i = 0; i < arr.length; i++) {
			System.out.print(arr[i]);
			try {
				Thread.sleep(1000);
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
		}

	}

}

测试类

​package com.imooc.thread.exercise3_6;

public class TestLetter {

	public static void main(String[] args) {
		Letter l = new Letter();
		Thread td = new Thread(l);
		td.start();


	}

}