主流有几种方法，一种是用下面的函数
public static String getProperty(String key)

一种是用命令行来获取

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.util.ArrayList;
import java.util.Formatter;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Properties;

public class test {
    //通过截取cmd流方式得到计算机的配置信息(不好)
    public static List<String> getIpAddress() {
        Process p = null;
        List<String> address = new ArrayList<String>();
        try {
            p = new ProcessBuilder("ipconfig", "/all").start();
        } catch (Exception e) {
            return address;
        }
        StringBuffer sb = new StringBuffer();
        //读取进程输出值
        InputStream inputStream = p.getInputStream();
        BufferedReader br = new BufferedReader(new InputStreamReader(inputStream));
        String s = "";
        try {
            while ((s = br.readLine()) != null) {
                sb.append(s + "\n");
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                inputStream.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        System.out.println(sb);
        return address;
    }

    public static void getIpconfig() {
        Map<String, String> map = System.getenv();
        System.out.println(map.get("USERNAME"));//获取用户名
        System.out.println(map.get("COMPUTERNAME"));//获取计算机名
        System.out.println(map.get("USERDOMAIN"));//获取计算机域名
    }

    //得到计算机的ip地址和mac地址
    public static void getConfig() {
        try {
            InetAddress address = InetAddress.getLocalHost();
            NetworkInterface ni = NetworkInterface.getByInetAddress(address);
            //ni.getInetAddresses().nextElement().getAddress();
            byte[] mac = ni.getHardwareAddress();
            String sIP = address.getHostAddress();
            String sMAC = "";
            Formatter formatter = new Formatter();
            for (int i = 0; i < mac.length; i++) {
                sMAC = formatter.format(Locale.getDefault(), "%02X%s", mac[i],
                        (i < mac.length - 1) ? "-" : "").toString();
            }
            System.out.println("IP：" + sIP);
            System.out.println("MAC：" + sMAC);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    //得到计算机的ip,名称,操作系统名称,操作系统版本
    public static void Config() {
        try {
            InetAddress addr = InetAddress.getLocalHost();
            String ip = addr.getHostAddress().toString(); //获取本机ip
            String hostName = addr.getHostName().toString(); //获取本机计算机名称
            System.out.println("本机IP：" + ip + "\n本机名称:" + hostName);
            Properties props = System.getProperties();
            System.out.println("操作系统的名称：" + props.getProperty("os.name"));
            System.out.println("操作系统的版本：" + props.getProperty("os.version"));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    //其它的一些东西,会有用到的时候的
    public static void all() {
        Properties props = System.getProperties();
        System.out.println("Java的运行环境版本：" + props.getProperty("java.version"));
        System.out.println("Java的运行环境供应商：" + props.getProperty("java.vendor"));
        System.out.println("Java供应商的URL：" + props.getProperty("java.vendor.url"));
        System.out.println("Java的安装路径：" + props.getProperty("java.home"));
        System.out.println("Java的虚拟机规范版本：" + props.getProperty("java.vm.specification.version"));
        System.out.println("Java的虚拟机规范供应商：" + props.getProperty("java.vm.specification.vendor"));
        System.out.println("Java的虚拟机规范名称：" + props.getProperty("java.vm.specification.name"));
        System.out.println("Java的虚拟机实现版本：" + props.getProperty("java.vm.version"));
        System.out.println("Java的虚拟机实现供应商：" + props.getProperty("java.vm.vendor"));
        System.out.println("Java的虚拟机实现名称：" + props.getProperty("java.vm.name"));
        System.out.println("Java运行时环境规范版本：" + props.getProperty("java.specification.version"));
        System.out.println("Java运行时环境规范供应商：" + props.getProperty("java.specification.vender"));
        System.out.println("Java运行时环境规范名称：" + props.getProperty("java.specification.name"));
        System.out.println("Java的类格式版本号：" + props.getProperty("java.class.version"));
        System.out.println("Java的类路径：" + props.getProperty("java.class.path"));
        System.out.println("加载库时搜索的路径列表：" + props.getProperty("java.library.path"));
        System.out.println("默认的临时文件路径：" + props.getProperty("java.io.tmpdir"));
        System.out.println("一个或多个扩展目录的路径：" + props.getProperty("java.ext.dirs"));
        System.out.println("操作系统的名称：" + props.getProperty("os.name"));
        System.out.println("操作系统的构架：" + props.getProperty("os.arch"));
        System.out.println("操作系统的版本：" + props.getProperty("os.version"));
        System.out.println("文件分隔符：" + props.getProperty("file.separator"));
        //在 unix 系统中是＂／＂
        System.out.println("路径分隔符：" + props.getProperty("path.separator"));
        //在 unix 系统中是＂:＂
        System.out.println("行分隔符：" + props.getProperty("line.separator"));
        //在 unix 系统中是＂/n＂
        System.out.println("用户的账户名称：" + props.getProperty("user.name"));
        System.out.println("用户的主目录：" + props.getProperty("user.home"));
        System.out.println("用户的当前工作目录：" + props.getProperty("user.dir"));
    }

    public static void main(String[] args) {
        getConfig();
        Config();
        all();
    }
}