Java static member variable, static code block execution test

Java class object static member variables, static code blocks load execution order.

Package com.yjm.pro;import java.io.ioexception;import java.util.properties;public class  Pro { public static String url; public static String  username; public static string password; public static string  classforname; public static string log; public static properties  PROPERTIES; STATIC {  SYSTEM.OUT.PRINTLN ("Class static code block    Execute test ....");   Properties = new properties ();   try {   properties.load ( Pro.class.getResourceAsStream ("pro.properties"));    url = properties.getproperty ("url ");    username = properties.getproperty (" username ");    password =  properties.getproperty ("password");    log = properties.getproperty ("Log");    classforname = propertiEs     .getproperty ("Classforname");  } catch  (IOException e )  {   e.printstacktrace ();   } }}

Test code

public static void Main (string[] args) {//test1 ();  Test2 ();  Test3 (); Test4 ();  } private static void Test4 () {System.out.println (pro.class); SYSTEM.OUT.PRINTLN ("Class static variable" + Pro.log); }

Execution results

Class Com.yjm.pro.Pro
Class static code block executes test ....
Class static Variable Yes

Test class static data that executes static code blocks only when the class is referenced.

Java static member variable, static code block execution test