In laymans terms what does static mean in Java

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I have been told several definitions for it  looked on Wikipedia  but as a beginner to Java I m still not sure what it means  Anybody fluent in Java

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In addition to what  inkedmn has pointed out  a static member is at the class level  Therefore  the said member is loaded into memory by the JVM once for that class  when the class is loaded   That is  there aren t n instances of a static member loaded for n instances of the class to which it belongs

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Another great example of when static attributes and operations are used when you want to apply the Singleton design pattern  In a nutshell  the Singleton design pattern ensures that one and only one object of a particular class is ever constructeed during the lifetime of your system  to ensure that only one object is ever constructed  typical implemenations of the Singleton pattern keep an internal static reference to the single allowed object instance  and access to that instance is controlled using a static operation

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static means that the variable or method marked as such is available at the class level  In other words  you don t need to create an instance of the class to access it   public class Foo       public static void doStuff               does stuff           So  instead of creating an instance of Foo and then calling doStuff like this   Foo f   new Foo    f doStuff      You just call the method directly against the class  like so   Foo doStuff

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In very laymen terms the class is a mold and the object is the copy made with that mold  Static belong to the mold and can be accessed directly without making any copies  hence the example above

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Above points are correct and I want to add some more important points about Static keyword   Internally what happening when you are using static keyword is  it will store in permanent memory that is in heap memory  we know that there are two types of memory they are stack memory temporary memory  and heap memory permanent memory  so if you are not using static key word then will store in temporary memory that is in stack memory or you can call it as volatile memory    so you will get a doubt that what is the use of this right     example  static int a 10  1 program   just now I told if you use static keyword for variables or for method it will store in permanent memory right   so I declared same variable with keyword static  in other program with different value   example  static int a 20  2 program   the variable  a  is stored in heap memory by program 1 the same static variable  a  is found in program 2 at that time it won t create once again  a  variable in heap memory instead of that it just replace value of a from 10 to 20   In general it will create once again variable  a  in stack memory temporary memory  if you won t declare  a  as static variable      overall i can say that if we use static keyword    nbsp  1 we can save memory   nbsp  2 we can avoid duplicates   nbsp  3 No need of creating object in-order to access static variable with the help of class   name you can access it

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The static keyword can be used in several different ways in Java and in almost all cases it is a modifier which means the thing it is modifying is usable without an enclosing object instance   Java is an object oriented language and by default most code that you write requires an instance of the object to be used   public class SomeObject       public int someField      public void someMethod            public Class SomeInnerClass          In order to use someField  someMethod  or SomeInnerClass I have to first create an instance of SomeObject   public class SomeOtherObject       public void doSomeStuff             SomeObject anInstance   new SomeObject            anInstance someField   7          anInstance someMethod              Non-static inner classes are usually not created outside of the           class instance so you don t normally see this syntax         SomeInnerClass blah   anInstance new SomeInnerClass              If I declare those things static then they do not require an enclosing instance   public class SomeObjectWithStaticStuff       public static int someField      public static void someMethod            public static Class SomeInnerClass         public class SomeOtherObject       public void doSomeStuff             SomeObjectWithStaticStuff someField   7          SomeObjectWithStaticStuff someMethod            SomeObjectWithStaticStuff SomeInnerClass blah   new SomeObjectWithStaticStuff SomeInnerClass              Or you can also do this if your imports are correct         SomeInnerClass blah2   new SomeInnerClass              Declaring something static has several implications     First  there can only ever one value of a static field throughout your entire application   public class SomeOtherObject       public void doSomeStuff               Two objects  two different values         SomeObject instanceOne   new SomeObject            SomeObject instanceTwo   new SomeObject            instanceOne someField   7          instanceTwo someField   10            Static object  only ever one value         SomeObjectWithStaticStuff someField   7          SomeObjectWithStaticStuff someField   10    Redefines the above set           The second issue is that static methods and inner classes cannot access fields in the enclosing object  since there isn t one    public class SomeObjectWithStaticStuff       private int nonStaticField      private void nonStaticMethod             public static void someStaticMethod             nonStaticField   7    Not allowed         this nonStaticField   7    Not allowed  can never use  this  in static         nonStaticMethod      Not allowed         super someSuperMethod      Not allowed  can never use  super  in static            public static class SomeStaticInnerClass            public void doStuff                 someStaticField   7    Not allowed             nonStaticMethod      Not allowed             someStaticMethod      This is ok                      The static keyword can also be applied to inner interfaces  annotations  and enums   public class SomeObject       public static interface SomeInterface          public static  interface SomeAnnotation          public static enum SomeEnum          In all of these cases the keyword is redundant and has no effect   Interfaces  annotations  and enums are static by default because they never have a relationship to an inner class   This just describes what they keyword does   It does not describe whether the use of the keyword is a bad idea or not   That can be covered in more detail in other questions such as Is using a lot of static methods a bad thing    There are also a few less common uses of the keyword static   There are static imports which allow you to use static types  including interfaces  annotations  and enums not redundantly marked static  unqualified     SomeStaticThing java public class SomeStaticThing       public static int StaticCounterOne   0       SomeOtherStaticThing java public class SomeOtherStaticThing       public static int StaticCounterTwo   0       SomeOtherClass java import static some package SomeStaticThing    import some package SomeOtherStaticThing     public class SomeOtherClass       public void doStuff             StaticCounterOne      Ok         StaticCounterTwo      Not ok         SomeOtherStaticThing StaticCounterTwo      Ok           Lastly  there are static initializers which are blocks of code that are run when the class is first loaded  which is usually just before a class is instantiated for the first time in an application  and  like static methods  cannot access non-static fields or methods   public class SomeObject        private static int x       static           x   7

[java] In laymans terms, what does 'static' mean in Java?

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