java의 (Runtime.getRuntime()).exec 을 이용해 top 결과를 받고 싶습니다.

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
 
public class TOP {
 
	public static void main(String[] args) {
		Runtime rt = Runtime.getRuntime();
		Process p = null;
		try {
			p = rt.exec("top -b -n 1");
			BufferedReader in = new BufferedReader(new InputStreamReader(p
					.getInputStream()));
 
			String cl = null;
			while ((cl = in.readLine()) != null) {
				System.out.print(cl);
				System.out.print("\n");
			}
 
			System.out.print("\n");
			in.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}