Java如何获取系统cpu、内存、硬盘信息-白红宇

Java如何获取系统cpu、内存、硬盘信息

阅读量：5871 次

发布时间：2019-06-19

本文共 22948 字，大约阅读时间需要 76 分钟。

1 概述

　　前段时间摸索在Java中怎么获取系统信息包括cpu、内存、硬盘信息等，刚开始使用Java自带的包进行获取，但这样获取的内存信息不够准确并且容易出现找不到相应包等错误，所以后面使用sigar插件进行获取。下面列举出了这两种方式获取系统信息的方式及代码。

2 使用Java自带包获取系统信息

2.1 使用Java自带包获取系统信息代码如下：

2.1.1 Bytes.java

复制代码

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;

}

复制代码

2.1.2 IMonitorService.java

public interface IMonitorService {

public MonitorInfoBean getMonitorInfoBean() throws Exception;

}

2.1.3 MonitorInfoBean.java

复制代码

public class MonitorInfoBean {

private long totalMemory;

private long freeMemory;

private long maxMemory;

private String osName;

private long totalMemorySize;

private long freePhysicalMemorySize;

private long usedMemory;

private int totalThread;

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;}

}

复制代码

2.1.4

复制代码

import java.io.InputStreamReader;

import java.io.LineNumberReader;

//import sun.management.ManagementFactory;

//import com.sun.management.OperatingSystemMXBean;

import java.io.*;

import java.lang.management.ManagementFactory;

import java.util.StringTokenizer;

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;

public MonitorInfoBean getMonitorInfoBean() throws Exception {    int kb = 1024;    long totalMemory = Runtime.getRuntime().totalMemory() / kb;    long freeMemory = Runtime.getRuntime().freeMemory() / kb;    long maxMemory = Runtime.getRuntime().maxMemory() / kb;    // OperatingSystemMXBean osmxb = (OperatingSystemMXBean)    // ManagementFactory    // .getOperatingSystemMXBean();    // String osName = System.getProperty("os.name");    // long totalMemorySize = osmxb.getTotalPhysicalMemorySize() / kb;    // long freePhysicalMemorySize = osmxb.getFreePhysicalMemorySize() / kb;    // long usedMemory = (osmxb.getTotalPhysicalMemorySize() - osmxb    // .getFreePhysicalMemorySize()) / kb;    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();    // }    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());    }}private double getCpuRatioForWindows() {    try {        String procCmd = System.getenv("windir")                + "\\system32\\wbem\\wmic.exe process get Caption,CommandLine,"                + "KernelModeTime,ReadOperationCount,ThreadCount,UserModeTime,WriteOperationCount";        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;    }}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;            }            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;}public static void main(String[] args) throws Exception {    IMonitorService service = new MonitorServiceImpl();    MonitorInfoBean monitorInfo = service.getMonitorInfoBean();    System.out.println("cpu percent: " + monitorInfo.getCpuRatio());    System.out.println("can use memory: " + monitorInfo.getTotalMemory());    System.out.println("ideal memory: " + monitorInfo.getFreeMemory());    System.out.println("largest memory: " + monitorInfo.getMaxMemory());    System.out.println("all memory: " + monitorInfo.getTotalMemorySize() + "kb");    System.out.println("ideal memory: " + monitorInfo.getFreeMemory() + "kb");    System.out.println("used memory: " + monitorInfo.getUsedMemory() + "kb");    System.out.println("thread num: " + monitorInfo.getTotalThread() + "kb");}

}

复制代码

2.2 执行结果如下图所示：

3 使用sigar获取系统信息

3.1 下载安装sigar-1.6.4.zip

使用java自带的包获取系统数据，容易找不到包，尤其是内存信息不够准确，所以选择使用sigar获取系统信息。   下载地址：http://sourceforge.net/projects/sigar/files/latest/download?source=files解压压缩包，将lib下sigar.jar导入eclipse的CLASSPATH中，再将sigar-x86-winnt.dll存入Java的bin目录即可。

3.2 代码实现如下：

复制代码

import java.net.InetAddress;

import java.net.UnknownHostException;

import java.util.Map;

import java.util.Properties;

import org.hyperic.sigar.CpuInfo;

import org.hyperic.sigar.CpuPerc;

import org.hyperic.sigar.FileSystem;

import org.hyperic.sigar.FileSystemUsage;

import org.hyperic.sigar.Mem;

import org.hyperic.sigar.NetFlags;

import org.hyperic.sigar.NetInterfaceConfig;

import org.hyperic.sigar.NetInterfaceStat;

import org.hyperic.sigar.OperatingSystem;

import org.hyperic.sigar.Sigar;

import org.hyperic.sigar.SigarException;

import org.hyperic.sigar.Swap;

import org.hyperic.sigar.Who;

public class RuntimeTest {

public static void main(String[] args) {

try {

// System信息，从jvm获取

property();