有什么区别
ArrayList<Integer> list = new ArrayList<>();
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和
ArrayList<Integer> list = new ArrayList();
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当我创建一个新的ArrayList时,是菱形运算符吗?
为什么我可以访问该getName()方法?我的类没有扩展类Thread只是实现接口Runnable.
public class MyThread implements Runnable {
public void run() {
System.out.println("MyThread is running");
}
public static void main(String[] args){
MyThread thread1 = new MyThread();
Thread thr = new Thread(thread1, "thread");
thr.start();
System.out.println(thr.currentThread().getName());
System.out.println(thr.getName());//Why do I have access to this method?
}
}
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