/*** properties 特有的方法*/
public class Demo2 {public static void main(String[] args) {Properties prop = new Properties();//添加prop.setProperty("a", "宝马");prop.setProperty("b", "奔驰");prop.setProperty("c", "奥迪");System.out.println(prop);//根据键查值String property = prop.getProperty("b");System.out.println(property);//遍历 获得所有键的 set集合Set<String> strings = prop.stringPropertyNames();for (String key : strings) {String value = prop.getProperty(key);System.out.println(key + "    " + value);}}
}