why inner class in java?
602892
We use inner classes to logically group classes and interfaces in one place so that it can be more readable and maintainable. Additionally, it can access all the members of outer class including private data members and methods.
1017960
Java doesn't require a constructor when we create a class. However, it's important to know what happens under the hood when no constructors are explicitly defined. The compiler automatically provides a public no-argument constructor for any class without constructors. This is called the default constructor.
997134
Pick up some skills here. In Java programming, nested and inner classes often go hand in hand. A class that is defined within another class is called a nested class. An inner class, on the other hand, is a non-static type, a particular specimen of a nested class.
423812
Instance variables can be initialized in constructors, where error handling or other logic can be used. To provide the same capability for class variables, the Java programming language includes static initialization blocks. ... It is only necessary that they be declared and initialized before they are used.
1099514
Instantiation: The new keyword is a Java operator that creates the object. Initialization: The new operator is followed by a call to a constructor, which initializes the new object.
1377142
The main() method is static so that JVM can invoke it without instantiating the class. ... Void: It is a keyword and used to specify that a method doesn't return anything. As main() method doesn't return anything, its return type is void. As soon as the main() method terminates, the java program terminates too.
823650
Data types are especially important in Java because it is a strongly typed language. This means that all operations are type-checked by the compiler for type compatibility. Illegal operations will not be compiled. Thus, strong type checking helps prevent errors and enhances reliability.
378001
An abstract class is a class that is declared abstract —it may or may not include abstract methods. Abstract classes cannot be instantiated, but they can be subclassed. When an abstract class is subclassed, the subclass usually provides implementations for all of the abstract methods in its parent class.
797081
inner classes are in the same file, whereas subclasses can be in another file, maybe in another package. You cannot get an instance of an inner class without an instance of the class that contains it. inner classes have the methods they want, whereas subclasses have the methods of their parent class.
1043926
It is used to achieve total abstraction. Since java does not support multiple inheritance in case of class, but by using interface it can achieve multiple inheritance . It is also used to achieve loose coupling. Interfaces are used to implement abstraction.
1039537
The three parts of a simple empty class in java are; A simple empty class of java supports legacy, as it automatically acquires object class, therefore can produce the functionality described in the object hierarchy. It automatically generates a fault constructor inside the class with a blank description.
84716
In java, we have static instance variables as well as static methods and also static block. Classes can also be made static in Java. In java, we can't make Top-level (outer) class static. Only nested classes can be static.
882026
A really bad idea is to nest loops inside loops as that also means taking care of several iterator variables (i,j,k,l,m...). You can avoid heavy nesting and loops inside loops with specialized tool methods.
121346
While the Java 11 compiler behaves exactly as you would expect and prevents illegal access, the same is not true for the run time. To offer a modicum of backwards compatibility it eases migration and improves the chances of applications built on Java 8 to run on Java 11 by granting access to internal classes.
1006009
Encapsulation is essentially "data hiding". A class is a construct that can be instantiated to create objects in memory. The class will use encapsulation (e.g. public and private methods) to hide attributes that you don't want to allow public access to. Finally an instance of the class will be created.
76909
So, Yes, you can declare a class static in Java, provided the class is inside a top-level class. Such clauses are also known as nested classes and they can be declared static, but if you are thinking to make a top-level class static in Java, then it's not allowed.
74316
A String in Java is actually a non-primitive data type, because it refers to an object. The String object has methods that are used to perform certain operations on strings.