java获得CPU使用率,系统内存,虚拟…

程序计算时间：

longstartTime=System.currentTimeMillis();  //获取开始时间

。。。。。。。。。。。。
long endTime=System.currentTimeMillis(); //获取结束时间

System.out.println("程序运行时间： "+(endTime-startTime)+"ms(毫秒)");






 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 {  
      
    private longtotalMemory;   
    
      
    private longfreeMemory;   
    
      
    private longmaxMemory;   
    
      
    privateString osName;   
    
      
    private longtotalMemorySize;   
    
      
    private longfreePhysicalMemorySize;   
    
      
    private longusedMemory;   
    
      
    private inttotalThread;   
    
      
    privatedouble cpuRatio;   
 
    public longgetFreeMemory() {   
       return freeMemory;   
   }   
 
    public voidsetFreeMemory(long freeMemory) {  
       this.freeMemory = freeMemory;  
   }   
 
    public longgetFreePhysicalMemorySize() {  
       return freePhysicalMemorySize;  
   }   
 
    public voidsetFreePhysicalMemorySize(long freePhysicalMemorySize){   
       this.freePhysicalMemorySize =freePhysicalMemorySize;   
   }   
 
    public longgetMaxMemory() {   
       return maxMemory;   
   }   
 
    public voidsetMaxMemory(long maxMemory) {  
       this.maxMemory = maxMemory;  
   }   
 
    publicString getOsName() {   
       return osName;   
   }   
 
    public voidsetOsName(String osName) {  
       this.osName = osName;   
   }   
 
    public longgetTotalMemory() {   
       return totalMemory;   
   }   
 
    public voidsetTotalMemory(long totalMemory) {  
       this.totalMemory = totalMemory;  
   }   
 
    public longgetTotalMemorySize() {   
       return totalMemorySize;   
   }   
 
    public voidsetTotalMemorySize(long totalMemorySize) {  
       this.totalMemorySize = totalMemorySize;  
   }   
 
    public intgetTotalThread() {   
       return totalThread;   
   }   
 
    public voidsetTotalThread(int totalThread) {  
       this.totalThread = totalThread;  
   }   
 
    public longgetUsedMemory() {   
       return usedMemory;   
   }   
 
    public voidsetUsedMemory(long usedMemory) {  
       this.usedMemory = usedMemory;  
   }   
 
    publicdouble getCpuRatio() {   
       return cpuRatio;   
   }   
 
    public voidsetCpuRatio(double cpuRatio) {  
       this.cpuRatio = cpuRatio;  
   }   
}   
 
   之后，建立bean的接口   
 
public interface IMonitorService {  
    publicMonitorInfoBean getMonitorInfoBean() throwsException;   
 
}   
 
 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;  
 
   
public class MonitorServiceImpl implements IMonitorService{   
    
    privatestatic final int CPUTIME = 30;  
 
    privatestatic final int PERCENT = 100;  
 
    privatestatic final int FAULTLENGTH = 10;  
    
    privatestatic final File versionFile = newFile("/proc/version");   
    privatestatic String linuxVersion = null;  
 
      
    publicMonitorInfoBean 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;   
   }   
    privatestatic 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 -n1");   
           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 = newStringTokenizer(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 = newFloat(system).floatValue();  
               float niceUsage = new Float(nice).floatValue();  
                
               return (userUsage+systemUsage+niceUsage)/100;  
           }else{   
               brStat.readLine();   
               brStat.readLine();   
                    
               tokenStat = newStringTokenizer(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 = newFloat(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);  
       }   
 
   }   
    privatestatic 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());  
       }   
   }   
 
 
      
    privatedouble getCpuRatioForWindows() {  
       try {   
           String procCmd = System.getenv("windir")  
                   + "\\system32\\wbem\\wmic.exe process getCaption,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;   
       }   
   }   
 
      
    privatelong[] readCpu(final Process proc) {  
       long[] retn = new long[2];  
       try {   
           proc.getOutputStream().close();  
           InputStreamReader ir = newInputStreamReader(proc.getInputStream());  
           LineNumberReader input = newLineNumberReader(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;   
   }   
    
      
    publicstatic void main(String[] args) throws Exception{   
       IMonitorService service = newMonitorServiceImpl();   
       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{   
    publicstatic String substring(String src, int start_idx, intend_idx){   
       byte[] b = src.getBytes();  
       String tgt = "";   
       for(int i=start_idx; i<=end_idx;i++){   
           tgt +=(char)b[i];   
       }   
       return tgt;   
   }   
}