JAVA跨平台读取环境变量实战

import java.io.BufferedReader;   
import java.io.InputStreamReader;   
import java.util.Properties;   
  
class Test   
{   
 // 返回当前系统变量的函数，结果放在一个Properties里边，这里只针对win2k以上的，其它系统可以自己改进   
 public Properties getEnv() throws Exception   
 {   
  Properties prop = new Properties();   
  String OS = System.getProperty("os.name").toLowerCase();   
  System.out.println("操作系统:" + OS);   
  Process p = null;   
  if (OS.indexOf("windows") > -1)   
  {   
   p = Runtime.getRuntime().exec("cmd /c set");   
  }   
   if(OS.indexOf("linux") > -1)   
         {   
            p = Runtime.getRuntime().exec("sh -c set");   
         }   
  BufferedReader br = new BufferedReader(new InputStreamReader(p.getInputStream()));   
  String line;   
  while ((line = br.readLine()) != null)   
  {   
   int i = line.indexOf("=");   
   if (i > -1)   
   {   
    String key = line.substring(0, i);   
    String value = line.substring(i + 1);