Static Members Static Variables & Methods SoftUni Team Technical Trainers Software University

2 1.Static Variables 2.Static Methods 3.Static Blocks Table of Contents

3 sli.do #1925 Questions

Static Variables 4

5  Static keyword  Marks field of method as static  Static elements  Belong to the class  Only one instance exists Static Keyword

6 Makes your program memory efficient Can be used to refer common property of all objects Static Variable

7 Class Student { String name; Integer studentsNumber; String university = “SoftUni” } Every instance will have ‘university’ field

8 Static Variable Class Student { String name; Integer studentsNumber; static String university = “SoftUni” } Shared between all class instances

Static Methods

10 Placed between access modifier and return type Static Methods public static String getUniversity name() { … }

11 Invoke method without creating new instance Static Methods public static void main(String[] args) { System.out.println(Student.getUnivesity()); }

12 Can’t use non – static data members Can’t use non – static methods directly this & super can’t be used in static contexts Static Methods - Restrictions

Static Blocks

14 Used to initialize static data Static blocks are executed at the time of class loading Static Blocks

15 Static Blocks public class Main { static { System.out.println(“Static block”); } public static void main (String[] args) { }

Summary  Static Variables  Static Methods  Static Blocks 16

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