18th Day complement other objects

One other object-System

It is more important to know how to implement functionality by looking at the API documentation than how to use the methods that understand these classes.

Describes the various methods in the API.

One of the more important is that the getProperties () method can obtain system properties.

Properties is a subclass of Hashtable.

* Methods and properties in the system class are static;
* In: standard input, default is keyboard;
* out: Standard output, default is console.

/* * System: Describes some of the information about the systems.  * * Get System Properties Information: Properties GetProperties (); * */import java.util.*;p ublic class Demo {public static void main (string[]                args) {Properties prop = system.getproperties (); For (Object Obj:prop.keySet ()) {}}

18th Day complement other objects