java系统监控CPU 磁盘

import java.io.*;   
  
/**
* linux 下cpu 内存 磁盘 jvm的使用监控
* @author avery_leo
*
*/  
public class TT {   
    /**
      * 获取cpu使用情况
      * @return
      * @throws Exception
      */  
    public double getCpuUsage() throws Exception {   
        double cpuUsed = 0;   
  
         Runtime rt = Runtime.getRuntime();   
         Process p = rt.exec("top -b -n 1");// 调用系统的“top"命令   
       
  
         BufferedReader in = null;   
        try {   
             in = new BufferedReader(new InputStreamReader(p.getInputStream()));   
             String str = null;   
             String[] strArray = null;   
           
            while ((str = in.readLine()) != null) {   
                int m = 0;   
                   
                if (str.indexOf(" R ") != -1) {// 只分析正在运行的进程，top进程本身除外 &&am