学步园

	Properties p=System.getProperties();
	for(Enumeration e=p.propertyNames(); e.hasMoreElements();){
		String key=(String) e.nextElement();
		System.out.println(key+"===>"+p.getProperty(key));
	}

方法二：

	Properties p=System.getProperties();
		for(Object t:p.keySet()){
			System.out.println(t+"="+p.getProperty(t.toString()));
		}