Declaring an inner class static means that class only has access to the "outer" class public and private static fields. A non-static inner class has access to the outer class's instance data. Top-level classes cannot be declared static.
The advantage of a static inner class is that it doesn't need an instance of the containing class to work and it's bytecode class size is smaller for that reason - less overhead.
There is no separate entity as a static object in java. The static keyword in java is used to signify that the member (either a variable or a method) is not associated to an object instance of the class. It signifies the fact that the member belongs to the class as a whole. The words static and objects are opposites of one another so you cannot have a static object. However, you can declare an object as a class level variable which could be referred to as a static object but it will be referred to as a static or class variable and not a static object.
Static java method is the same as a static variable. They belong to a class and not an object of that class. If a method needs to be in a class, but not tied to an object, then one uses static java.
if some method is static, then you can not call that method through the oobject of that class. but the name of the class. let us see a example: class Test { int a; int b; static void show() { System.out.println("we are in show"); } } class Main { public static void main(String args[]) { Test t=new Test(); t.show();\\thiss is an erroraneous code. because, the method "show()" is static. Test.show();\\this is correct } Arnas Sinha
class MyClass extends AnotherClass {}
when overriding of a class or a method is necessary, they can be declared as abstract
There is no separate entity as a static object in java. The static keyword in java is used to signify that the member (either a variable or a method) is not associated to an object instance of the class. It signifies the fact that the member belongs to the class as a whole. The words static and objects are opposites of one another so you cannot have a static object. However, you can declare an object as a class level variable which could be referred to as a static object but it will be referred to as a static or class variable and not a static object.
You declare a member static whenever the member should be regarded as being local to the class rather than being local to objects of the class. Static members are shared by all instances of the class. Static methods of a class differ from ordinary members in that they do not have an implicit "this" reference, which means they can be invoked even when no instances of the class exist.
Static java method is the same as a static variable. They belong to a class and not an object of that class. If a method needs to be in a class, but not tied to an object, then one uses static java.
You can declare a class as "final".
Declare the class as final. final class A{ ... }
if some method is static, then you can not call that method through the oobject of that class. but the name of the class. let us see a example: class Test { int a; int b; static void show() { System.out.println("we are in show"); } } class Main { public static void main(String args[]) { Test t=new Test(); t.show();\\thiss is an erroraneous code. because, the method "show()" is static. Test.show();\\this is correct } Arnas Sinha
It will get a compiler error in Java.
class MyClass extends AnotherClass {}
It is uss to define class and method of pogrom's.
when overriding of a class or a method is necessary, they can be declared as abstract
In the case a Java, if a variable at the class level (called a "field" in Java) is declared as static, a single copy of such a variable exists, no matter how many objects are created for the class. This lets you share information between different objects; you can also access such a variable without creating a single object, using the class name. A good example are the fields Math.PI and Math.E, i.e., fields in the "Math" class which you can access without creating an object based on the class.
Static import is a java feature that introduced in Java 5. Static imports allow you to import static members of a class to be used without the class qualifier. And its also it should used in a moderate manner. If you overuse the static import feature, it can make your program unreadable and unmaintainable, polluting its namespace with all the static members you import. Source- Oracle documentation. Marcus Biel Clean Code Course