Process p = Runtime.getruntime.exec(cmd);
BufferReader br = new BufferedRead(new InputStreamReader(p.getInputStream()));
for (String buf=br.readLine(); buf != null; buf=br.readLine()) {
    System.out.println(buf);
}

------解决方案--------------------

Java code

import java.io.*;
import java.util.regex.*;

public class GetPID {
    public static void main(String[] args) {
        Process process = null;
        BufferedReader br = null;
        try {
            process = Runtime.getRuntime().exec("ps -ef");
            br = new BufferedReader(new InputStreamReader(
                        process.getInputStream()), 1024);
            String line = null;
            Pattern pattern = Pattern.compile("\\S*\\s*([0-9]*).*");
            Matcher matcher = null;
            System.out.println("PID list: ");
            while ((line = br.readLine()) != null) {
                matcher = pattern.matcher(line);
                if (matcher.find()) {
                    System.out.println(matcher.group(1));
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (process != null) {
                int retval = 0;
                try {
                    retval = process.waitFor();
                    System.out.println("retval = " + retval);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                } finally {
                    if (br != null) {
                        try {
                            br.close();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                    }
                }
            }
        }
    }
}