如何利用Java獲取系統的資訊(CPU、記憶體、各碟符使用情況)
阿新 • • 發佈:2019-02-02
/*********************************************************************** * Project: gpsAdapter * Note: Console Application **********************************************************************/ /** * * @author HuangHaifeng 1.0 * @date 2016-1-12 * @copyright CCompass * 增加用於監控系統cpu,memory的工具類 */ package com.hhf.test; 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 javax.management.MBeanServerConnection; import javax.management.remote.JMXConnector; import javax.management.remote.JMXConnectorFactory; import javax.management.remote.JMXServiceURL; import com.sun.management.OperatingSystemMXBean; public class WindowsInfoUtil { private static final int CPUTIME = 500; private static final int PERCENT = 100; private static final int FAULTLENGTH = 10; // 獲取記憶體使用率 public static String getMemery() { OperatingSystemMXBean osmxb = ManagementFactory.getPlatformMXBean(OperatingSystemMXBean.class); long totalvirtualMemory = osmxb.getTotalSwapSpaceSize(); // 剩餘的實體記憶體 long freePhysicalMemorySize = osmxb.getFreePhysicalMemorySize(); Double compare = (Double) (1 - freePhysicalMemorySize * 1.0 / totalvirtualMemory) * 100; String str = compare.intValue() + "%"; return str; } // 獲取檔案系統使用率 public static List<String> getDisk() { // 作業系統 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 + ":盤已使用" + compare.intValue() + "%"; list.add(str); } } return list; } // 獲得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"; // 取程序資訊 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) * 1.0 / (busytime + idletime)).intValue() + "%"; } else { return 0 + "%"; } } catch (Exception ex) { ex.printStackTrace(); return 0 + "%"; } } 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; } // 欄位出現順序: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; } String s1 = Bytes.substring(line, kmtidx, rocidx - 1).trim(); String s2 = Bytes.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; } static 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; } } public static void main(String[] args) throws Exception { System.out.println("cpu佔有率=" + WindowsInfoUtil.getCpuRatioForWindows()); System.out.println("可使用記憶體=" + WindowsInfoUtil.getMemery()); System.out.println("各盤佔用情況:" + WindowsInfoUtil.getDisk()); } }
這時就會出現com.sun.management.OperatingSystemMXBean這個類找不到!
這裡的工程需要用到rt.jar,當我們額外下載匯入rt.jar就可以解決這個問題,但是對於jdk來說本身是具有jar包的,原因是eclipse將這些訪問受限制的API設定成了錯誤,導致不能import。