java获取cpu使用率内存使用率硬盘的使用率

import java.io.File; import java.io.InputStreamReader; import java.io.LineNumberReader; import java.lang.management.ManagementFactory; import java.util.ArrayList; import java.util.List;

import com.sun.management.OperatingSystemMXBean;

/**  * 获取windows系统信息（CPU,内存,文件系统）  *  * @author libing  *  */

public class WindowsInfoUtil {  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();   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：   *   * @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;  } }