获取Linux(redhat)系统的一些基本信息

package com.sundy.util;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;import java.text.DecimalFormat;import java.util.Properties;public class LinuxUtil {/** * 获取CPU的数量 * @return */public static int getCPUNumber(){return Runtime.getRuntime().availableProcessors();} /**     * 获取CPU使用率      * @return 如： 32.54%     */    public static String getCPUUsage() throws IOException{          float cpuUsage = 0;            Process pro1,pro2;            Runtime r = Runtime.getRuntime();            try {                String command = "cat /proc/stat";                //第一次采集CPU时间                pro1 = r.exec(command);                BufferedReader in1 = new BufferedReader(new InputStreamReader(pro1.getInputStream()));                String line = null;                long idleCpuTime1 = 0, totalCpuTime1 = 0;   //分别为系统启动后空闲的CPU时间和总的CPU时间                while((line=in1.readLine()) != null){                       if(line.startsWith("cpu")){                        line = line.trim();                        String[] temp = line.split("\\s+");                         idleCpuTime1 = Long.parseLong(temp[4]);                        for(String s : temp){                            if(!s.equals("cpu")){                                totalCpuTime1 += Long.parseLong(s);                            }                        }                           break;                    }                                       }                   in1.close();                pro1.destroy();                try {                    Thread.sleep(1500);                } catch (InterruptedException e) {                e.printStackTrace();            }                //第二次采集CPU时间                pro2 = r.exec(command);                BufferedReader in2 = new BufferedReader(new InputStreamReader(pro2.getInputStream()));                long idleCpuTime2 = 0, totalCpuTime2 = 0;   //分别为系统启动后空闲的CPU时间和总的CPU时间                while((line=in2.readLine()) != null){                       if(line.startsWith("cpu")){                        line = line.trim();                        String[] temp = line.split("\\s+");                         idleCpuTime2 = Long.parseLong(temp[4]);                        for(String s : temp){                            if(!s.equals("cpu")){                                totalCpuTime2 += Long.parseLong(s);                            }                        }                        break;                      }              }              if(idleCpuTime1 != 0 && totalCpuTime1 !=0 && idleCpuTime2 != 0 && totalCpuTime2 !=0){                    cpuUsage = 1 - (float)(idleCpuTime2 - idleCpuTime1)/(float)(totalCpuTime2 - totalCpuTime1);                }                               in2.close();                pro2.destroy();            } catch (IOException e) {            e.printStackTrace();        }               return new DecimalFormat("##0.00").format(cpuUsage*100)+"%";      }      /**     * 获取可用的内存     * @return 如： 42.54%     * @throws IOException      */    public static String availableMemory() throws IOException{    Runtime runtime = Runtime.getRuntime();        String command = " free";        Process process = runtime.exec(command);        BufferedReader br = new BufferedReader(new InputStreamReader(process.getInputStream()));     String line = null;    long tatal = 0;    long available = 0;    long free = 0;    String str = null;    while((line=br.readLine())!=null){    if(line.startsWith("Mem:")){    String[] split = line.split("\\s+");    tatal = Long.valueOf(split[1]);    available = Long.valueOf(split[3])+Long.valueOf(split[5])+Long.valueOf(split[6]);    }    }    if(tatal!=0){    str = new DecimalFormat("##0.00").format((free+available)/(tatal*1.0f)*100);    }    if(br!=null) br.close();        if(process!=null) process.destroy();    return str==null?"0.00%":str+"%";    }    /**     * 已经用的内存     * @return 如： 42.54%     * @throws IOException      */    public static String usedMemory() throws IOException{    Runtime runtime = Runtime.getRuntime();        String command = " free";        Process process = runtime.exec(command);        BufferedReader br = new BufferedReader(new InputStreamReader(process.getInputStream()));         String line = null;        long tatal = 0;        long used = 0;        String str = null;        while((line=br.readLine())!=null){        if(line.startsWith("Mem:")){        String[] split = line.split("\\s+");        tatal = Long.valueOf(split[1]);        used = Long.valueOf(split[2])-Long.valueOf(split[5])-Long.valueOf(split[6]);        }        }        if(tatal!=0){        str = new DecimalFormat("##0.00").format(used/(tatal*1.0f)*100);        }        if(br!=null) br.close();        if(process!=null) process.destroy();    return str==null?"0.00%":str+"%";    }        /** * 磁盘使用率 * @return * @throws Exception  */public static String getDiskUsage() throws Exception{Long[] info = getDiskInfo();if(info==null || info.length<=0) return "0.00%";long total = info[0]+info[1];return new DecimalFormat("#0.00").format(info[0]/(total*1.0f));}/** * 已用磁盘空间情况 * @return 下标0为已用，1为可用。 */public static Long[] getDiskInfo() throws Exception{BufferedReader br = null ;Process process = null;Long[] str = null;try {Runtime runtime = Runtime.getRuntime();        String command = " df -a";        process = runtime.exec(command);        br = new BufferedReader(new InputStreamReader(process.getInputStream()));         String line = null;        while((line = br.readLine())!=null){        String[] split = line.split("\\s+");        if(line.startsWith("/dev")&&split.length>3){        str = new Long[2];        str[0] = Long.parseLong(line.split("\\s+")[2]);        str[1] =  Long.parseLong(line.split("\\s+")[3]);        break;        }else if(line.startsWith("")||line.startsWith(" ")){        str = new Long[2];        str[0] =  Long.parseLong(line.split("\\s+")[1]);        str[1] =  Long.parseLong(line.split("\\s+")[2]);        break;        }        }} catch (Exception e) {e.printStackTrace();}finally{if(process!=null) process.destroy();if(br!=null) br.close();}return str;}/** * 获取系统的信息 * @return下标0表示 系统名称，下标1表示系统版本 */public static String[] getSystemInfo(){Properties props = System.getProperties();String[] str = {props.getProperty("os.name"),props.getProperty("os.version")};return str;}}