从控制台读取时CPU使用率高

Question

So i am writing a little program that takes user input

public class Test {
    public static void main(String[] args) throws IOException {
        BufferedReader input = new BufferedReader(new InputStreamReader(System.in));
        String something = input.readLine();
    }
}

Here is the relavent section cut out, I run this and the main thread blocks on readline() but my CPU usage is ~15-20% consistently.

What is up here, is there a more efficient way to read from the console.

EDIT: I am on Mac OS 10.8 and the process has been running for 20 minutes now. The input.readline() statement is wrapped in a while true loop with some simple processing inside but i know the code is not getting there.

Answer 1

I assume you have some kind of code that checks the status of readLine(), otherwise Java will continue to block.

String line = null;
while ((line = br.readLine()) != null) {
    // handle contents of line here
}

You may be better off using the Scanner class to read user input.

Scanner sc = new Scanner(System.in);
int num = sc.nextInt();
....