Java等待下一次打印

Question

我希望第二次打印在2秒后发生.

System.out.println("First print.");
//I want the code that makes the next System.out.println in 2 seconds.
System.out.println("This one comes after 2 seconds from the println.");

Answer 1

只需使用Thread#sleep:

System.out.println("First print.");
Thread.sleep(2000);//2000ms = 2s
System.out.println("This one comes after 2 seconds from the println.");

注意,Thread.sleep可以抛出一个InterruptedException,所以你需要一个throws或一个子句try-catch,如:

System.out.println("First print.");
try{
    Thread.sleep(2000);//2000ms = 2s
}catch(InterruptedException ex){
}
System.out.println("This one comes after 2 seconds from the println.");

要么:

public void something() throws InterruptedException {
    System.out.println("First print.");
    Thread.sleep(2000);//2000ms = 2s
    System.out.println("This one comes after 2 seconds from the println.");
}