java获得CPU使用率,系统内存,虚拟机内存等情况

JXM：Monitoring and Management Interface for the Java™ Platform 

通过jmx可以监控vm内存使用,系统内存使用等 

以下是网上某博客代码，特点是通过window和linux命令获得CPU使用率。 

   利用java程序实现获取计算机cpu利用率和内存使用信息。     创建一个Bean用来存贮要得到的信 public class MonitorInfoBean {     /** 可使用内存. */     private long totalMemory;        /**  剩余内存. */     private long freeMemory;        /** 最大可使用内存. */     private long maxMemory;        /** 操作系统. */     private String osName;        /** 总的物理内存. */     private long totalMemorySize;        /** 剩余的物理内存. */     private long freePhysicalMemorySize;        /** 已使用的物理内存. */     private long usedMemory;        /** 线程总数. */     private int totalThread;        /** cpu使用率. */     private double cpuRatio;     public long getFreeMemory() {         return freeMemory;     }     public void setFreeMemory(long freeMemory) {         this.freeMemory = freeMemory;     }     public long getFreePhysicalMemorySize() {         return freePhysicalMemorySize;     }     public void setFreePhysicalMemorySize(long freePhysicalMemorySize) {         this.freePhysicalMemorySize = freePhysicalMemorySize;     }     public long getMaxMemory() {         return maxMemory;     }     public void setMaxMemory(long maxMemory) {         this.maxMemory = maxMemory;     }     public String getOsName() {         return osName;     }     public void setOsName(String osName) {         this.osName = osName;     }     public long getTotalMemory() {         return totalMemory;     }     public void setTotalMemory(long totalMemory) {         this.totalMemory = totalMemory;     }     public long getTotalMemorySize() {         return totalMemorySize;     }     public void setTotalMemorySize(long totalMemorySize) {         this.totalMemorySize = totalMemorySize;     }     public int getTotalThread() {         return totalThread;     }     public void setTotalThread(int totalThread) {         this.totalThread = totalThread;     }     public long getUsedMemory() {         return usedMemory;     }     public void setUsedMemory(long usedMemory) {         this.usedMemory = usedMemory;     }     public double getCpuRatio() {         return cpuRatio;     }     public void setCpuRatio(double cpuRatio) {         this.cpuRatio = cpuRatio;     } }     之后，建立bean的接口 public interface IMonitorService {     public MonitorInfoBean getMonitorInfoBean() throws Exception; }   然后，就是最关键的，得到cpu的利用率，已用内存，可用内存，最大内存等信息。 import java.io.InputStreamReader; import java.io.LineNumberReader; import sun.management.ManagementFactory; import com.sun.management.OperatingSystemMXBean; import java.io.*; import java.util.StringTokenizer; /** * 获取系统信息的业务逻辑实现类. * @author GuoHuang */ public class MonitorServiceImpl implements IMonitorService {        private static final int CPUTIME = 30;     private static final int PERCENT = 100;     private static final int FAULTLENGTH = 10;        private static final File versionFile = new File("/proc/version");     private static String linuxVersion = null;     /**      * 获得当前的监控对象.      * @return 返回构造好的监控对象      * @throws Exception      * @author GuoHuang      */     public MonitorInfoBean getMonitorInfoBean() throws Exception {         int kb = 1024;                // 可使用内存         long totalMemory = Runtime.getRuntime().totalMemory() / kb;         // 剩余内存         long freeMemory = Runtime.getRuntime().freeMemory() / kb;         // 最大可使用内存         long maxMemory = Runtime.getRuntime().maxMemory() / kb;         OperatingSystemMXBean osmxb = (OperatingSystemMXBean) ManagementFactory                 .getOperatingSystemMXBean();         // 操作系统         String osName = System.getProperty("os.name");         // 总的物理内存         long totalMemorySize = osmxb.getTotalPhysicalMemorySize() / kb;         // 剩余的物理内存         long freePhysicalMemorySize = osmxb.getFreePhysicalMemorySize() / kb;         // 已使用的物理内存         long usedMemory = (osmxb.getTotalPhysicalMemorySize() - osmxb                 .getFreePhysicalMemorySize())                 / kb;         // 获得线程总数         ThreadGroup parentThread;         for (parentThread = Thread.currentThread().getThreadGroup(); parentThread                 .getParent() != null; parentThread = parentThread.getParent())             ;         int totalThread = parentThread.activeCount();         double cpuRatio = 0;         if (osName.toLowerCase().startsWith("windows")) {             cpuRatio = this.getCpuRatioForWindows();         }         else {          cpuRatio = this.getCpuRateForLinux();         }                // 构造返回对象         MonitorInfoBean infoBean = new MonitorInfoBean();         infoBean.setFreeMemory(freeMemory);         infoBean.setFreePhysicalMemorySize(freePhysicalMemorySize);         infoBean.setMaxMemory(maxMemory);         infoBean.setOsName(osName);         infoBean.setTotalMemory(totalMemory);         infoBean.setTotalMemorySize(totalMemorySize);         infoBean.setTotalThread(totalThread);         infoBean.setUsedMemory(usedMemory);         infoBean.setCpuRatio(cpuRatio);         return infoBean;     }     private static double getCpuRateForLinux(){         InputStream is = null;         InputStreamReader isr = null;         BufferedReader brStat = null;         StringTokenizer tokenStat = null;         try{             System.out.println("Get usage rate of CUP , linux version: "+linuxVersion);             Process process = Runtime.getRuntime().exec("top -b -n 1");             is = process.getInputStream();                               isr = new InputStreamReader(is);             brStat = new BufferedReader(isr);                        if(linuxVersion.equals("2.4")){                 brStat.readLine();                 brStat.readLine();                 brStat.readLine();                 brStat.readLine();                                tokenStat = new StringTokenizer(brStat.readLine());                 tokenStat.nextToken();                 tokenStat.nextToken();                 String user = tokenStat.nextToken();                 tokenStat.nextToken();                 String system = tokenStat.nextToken();                 tokenStat.nextToken();                 String nice = tokenStat.nextToken();                                System.out.println(user+" , "+system+" , "+nice);                                user = user.substring(0,user.indexOf("%"));                 system = system.substring(0,system.indexOf("%"));                 nice = nice.substring(0,nice.indexOf("%"));                                float userUsage = new Float(user).floatValue();                 float systemUsage = new Float(system).floatValue();                 float niceUsage = new Float(nice).floatValue();                                return (userUsage+systemUsage+niceUsage)/100;             }else{                 brStat.readLine();                 brStat.readLine();                                    tokenStat = new StringTokenizer(brStat.readLine());                 tokenStat.nextToken();                 tokenStat.nextToken();                 tokenStat.nextToken();                 tokenStat.nextToken();                 tokenStat.nextToken();                 tokenStat.nextToken();                 tokenStat.nextToken();                 String cpuUsage = tokenStat.nextToken();                                                   System.out.println("CPU idle : "+cpuUsage);                 Float usage = new Float(cpuUsage.substring(0,cpuUsage.indexOf("%")));                                return (1-usage.floatValue()/100);             }                     } catch(IOException ioe){             System.out.println(ioe.getMessage());             freeResource(is, isr, brStat);             return 1;         } finally{             freeResource(is, isr, brStat);         }     }     private static void freeResource(InputStream is, InputStreamReader isr, BufferedReader br){         try{             if(is!=null)                 is.close();             if(isr!=null)                 isr.close();             if(br!=null)                 br.close();         }catch(IOException ioe){             System.out.println(ioe.getMessage());         }     }     /**      * 获得CPU使用率.      * @return 返回cpu使用率      * @author GuoHuang      */     private double getCpuRatioForWindows() {         try {             String procCmd = System.getenv("windir")                     + "\\system32\\wbem\\wmic.exe process get Caption,CommandLine,"                     + "KernelModeTime,ReadOperationCount,ThreadCount,UserModeTime,WriteOperationCount";             // 取进程信息             long[] c0 = readCpu(Runtime.getRuntime().exec(procCmd));             Thread.sleep(CPUTIME);             long[] c1 = readCpu(Runtime.getRuntime().exec(procCmd));             if (c0 != null && c1 != null) {                 long idletime = c1[0] - c0[0];                 long busytime = c1[1] - c0[1];                 return Double.valueOf(                         PERCENT * (busytime) / (busytime + idletime))                         .doubleValue();             } else {                 return 0.0;             }         } catch (Exception ex) {             ex.printStackTrace();             return 0.0;         }     }     /**      * 读取CPU信息.      * @param proc      * @return      * @author GuoHuang      */     private long[] readCpu(final Process proc) {         long[] retn = new long[2];         try {             proc.getOutputStream().close();             InputStreamReader ir = new InputStreamReader(proc.getInputStream());             LineNumberReader input = new LineNumberReader(ir);             String line = input.readLine();             if (line == null || line.length() < FAULTLENGTH) {                 return null;             }             int capidx = line.indexOf("Caption");             int cmdidx = line.indexOf("CommandLine");             int rocidx = line.indexOf("ReadOperationCount");             int umtidx = line.indexOf("UserModeTime");             int kmtidx = line.indexOf("KernelModeTime");             int wocidx = line.indexOf("WriteOperationCount");             long idletime = 0;             long kneltime = 0;             long usertime = 0;             while ((line = input.readLine()) != null) {                 if (line.length() < wocidx) {                     continue;                 }                 // 字段出现顺序：Caption,CommandLine,KernelModeTime,ReadOperationCount,                 // ThreadCount,UserModeTime,WriteOperation                 String caption = Bytes.substring(line, capidx, cmdidx - 1)                         .trim();                 String cmd = Bytes.substring(line, cmdidx, kmtidx - 1).trim();                 if (cmd.indexOf("wmic.exe") >= 0) {                     continue;                 }                 // log.info("line="+line);                 if (caption.equals("System Idle Process")                         || caption.equals("System")) {                     idletime += Long.valueOf(                             Bytes.substring(line, kmtidx, rocidx - 1).trim())                             .longValue();                     idletime += Long.valueOf(                             Bytes.substring(line, umtidx, wocidx - 1).trim())                             .longValue();                     continue;                 }                 kneltime += Long.valueOf(                         Bytes.substring(line, kmtidx, rocidx - 1).trim())                         .longValue();                 usertime += Long.valueOf(                         Bytes.substring(line, umtidx, wocidx - 1).trim())                         .longValue();             }             retn[0] = idletime;             retn[1] = kneltime + usertime;             return retn;         } catch (Exception ex) {             ex.printStackTrace();         } finally {             try {                 proc.getInputStream().close();             } catch (Exception e) {                 e.printStackTrace();             }         }         return null;     }        /**     测试方法.      * @param args      * @throws Exception      * @author GuoHuang        */     public static void main(String[] args) throws Exception {         IMonitorService service = new MonitorServiceImpl();         MonitorInfoBean monitorInfo = service.getMonitorInfoBean();         System.out.println("cpu占有率=" + monitorInfo.getCpuRatio());                System.out.println("可使用内存=" + monitorInfo.getTotalMemory());         System.out.println("剩余内存=" + monitorInfo.getFreeMemory());         System.out.println("最大可使用内存=" + monitorInfo.getMaxMemory());                System.out.println("操作系统=" + monitorInfo.getOsName());         System.out.println("总的物理内存=" + monitorInfo.getTotalMemorySize() + "kb");         System.out.println("剩余的物理内存=" + monitorInfo.getFreeMemory() + "kb");         System.out.println("已使用的物理内存=" + monitorInfo.getUsedMemory() + "kb");         System.out.println("线程总数=" + monitorInfo.getTotalThread() + "kb");     } }     其中，Bytes类用来处理字符串    public class Bytes {     public static String substring(String src, int start_idx, int end_idx){         byte[] b = src.getBytes();         String tgt = "";         for(int i=start_idx; i<=end_idx; i++){             tgt +=(char)b[i];         }         return tgt;     } }