java 获取一些项目或系统属性

System.out.println(Object.class.getClassLoader());
  System.out.println(System.class.getClassLoader());
  System.out.println("the Launcher's classloader is "+sun.misc.Launcher.getLauncher().getClass().getClassLoader());
  System.out.println(System.getProperty("java.class.path"));
  
  URL[] urls=sun.misc.Launcher.getBootstrapClassPath().getURLs();
  for (int i = 0; i < urls.length; i++) {
   System.out.println(urls[i].toExternalForm().toString());
  }
  System.out.println("");
//  */
//  /*
  String s = System.getProperty("java.ext.dirs");
  if(s != null) {
   StringTokenizer stringtokenizer = new StringTokenizer(s, File.pathSeparator);
   int count = stringtokenizer.countTokens();
   for(int i=0;i<count;i++){
    System.out.println(stringtokenizer.nextToken());
   }
  }