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java获取cpu,内存,磁盘等信息

原文：java获取cpu,内存,磁盘等信息

源代码下载地址：http://www.zuidaima.com/share/1550463331306496.htm

package com.zuidaima.util;
import java.io.File;
import java.io.InputStreamReader; 
import java.io.LineNumberReader; 
import java.util.ArrayList; 
import java.util.List; 

import sun.management.ManagementFactory;

import com.sun.management.OperatingSystemMXBean;


/** 
* 获取windows系统信息（CPU,内存,文件系统） 
* @author www.zuidaima.com 
* 
*/ 

public class cpu { 
    private static final int CPUTIME = 500; 
    private static final int PERCENT = 100; 
    private static final int FAULTLENGTH = 10; 

    public static void main(String[] args) { 
    System.out.println(getCpuRatioForWindows()); 
    System.out.println(getMemery()); 
    System.out.println(getDisk()); 
} 

//获取内存使用率 
public static String getMemery(){ 
  OperatingSystemMXBean osmxb = (OperatingSystemMXBean) ManagementFactory.getOperatingSystemMXBean(); 
  // 总的物理内存+虚拟内存 
  long totalvirtualMemory = osmxb.getTotalSwapSpaceSize(); 
  // 剩余的物理内存 
  long freePhysicalMemorySize = osmxb.getFreePhysicalMemorySize();
  System.out.println("总  的  内 存"+(totalvirtualMemory/1024.0/1024.0/1024.0));
  System.out.println("使用的内存"+((totalvirtualMemory-freePhysicalMemorySize)/1024.0/1024.0/1024.0));
  Double compare=(Double)(1-freePhysicalMemorySize*1.0/totalvirtualMemory)*100; 
  String str="内存已使用:"+compare.intValue()+"%"; 
  return str; 
} 

//获取文件系统使用率 
public static List<String> getDisk() { 
  // 操作系统 
  List<String> list=new ArrayList<String>(); 
  for (char c = 'A'; c <= 'Z'; c++) { 
   String dirName = c + ":/"; 
   File win = new File(dirName); 
         if(win.exists()){ 
          long total=(long)win.getTotalSpace(); 
          long free=(long)win.getFreeSpace(); 
          Double compare=(Double)(1-free*1.0/total)*100; 
          String str=c+":盘  已使用 "+compare.intValue()+"%"; 
          list.add(str); 
         } 
     } 
        return list; 
} 

//获得cpu使用率 
public static String 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 "CPU使用率:"+Double.valueOf(PERCENT * (busytime)*1.0 / (busytime + idletime)).intValue()+"%"; 
             } else { 
                 return "CPU使用率:"+0+"%"; 
             } 
         } catch (Exception ex) { 
             ex.printStackTrace(); 
             return "CPU使用率:"+0+"%"; 
         } 
     } 

//读取cpu相关信息 
    private static 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 =substring(line, capidx, cmdidx - 1).trim(); 
                String cmd = substring(line, cmdidx, kmtidx - 1).trim(); 
                if (cmd.indexOf("wmic.exe") >= 0) { 
                    continue; 
                } 
                String s1 = substring(line, kmtidx, rocidx - 1).trim(); 
                String s2 = substring(line, umtidx, wocidx - 1).trim(); 
                if (caption.equals("System Idle Process") || caption.equals("System")) { 
                    if (s1.length() > 0) 
                        idletime += Long.valueOf(s1).longValue(); 
                    if (s2.length() > 0) 
                        idletime += Long.valueOf(s2).longValue(); 
                    continue; 
                } 
                if (s1.length() > 0) 
                    kneltime += Long.valueOf(s1).longValue(); 
                if (s2.length() > 0) 
                    usertime += Long.valueOf(s2).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; 
    } 

    /** 
   * 由于String.subString对汉字处理存在问题（把一个汉字视为一个字节)，因此在 包含汉字的字符串时存在隐患，现调整如下： 
   * @author www.zuidaima.com 
   * @param src 要截取的字符串 
   * @param start_idx 开始坐标（包括该坐标) 
   * @param end_idx 截止坐标（包括该坐标） 
   * @return 
   */ 
    private 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; 
  } 
}