Java-System class

Java-System class
The methods and properties in the System class are both static out and standard output. The default value is console. In is the standard input, and the default is the keyboard. GetProperties returns the Properties type to obtain system property information.
Properties is a subclass of HashTable, that is, a subclass in the Map set. You can use the map method to retrieve the subclass in the set.

Import java. util. properties; public class SystemDemo {public static void main (String [] args) {Properties pro = System. getProperties (); // obtain all attributes. for (Object obj: pro. keySet () {String value = (String) pro. get (obj); System. out. println (value);} // obtain the Property Information String value = System. getProperty ("OS. name "); System. out. println (value); // custom attribute information System. setProperty ("football", "good"); System. out. println (Syste M. getProperty ("football"); // dynamically load attribute information when jvm is started. // To be continued ...... }}