Any normal class which does not have any abstract method or a class that has an implementation of all the methods of its parent class or interface and its own methods is a concrete class.10 Haz 2019
Read moreCan you have multiple classes in a Java program?
Java is an object-oriented programming language. You can create multiple classes in Java and create a class hierarchy such that one class can call another class. Do not confuse this with Java inheritance because, in class inheritance, there is a parent-child relationship between classes.
Read moreHow many classes are in a program?
The correct answer to the question “How many Classes can be defined in a Single Program” is, option (d). As many as you want . Inside a program, you can mention any number of classes, since there is no restriction, but the only thing that should be remembered is that all their names should be different.
Read moreHow many types of classes we have in Java?
There are five kinds of classes: package-level, nested top-level, member, local, or anonymous. (The last four kinds are called inner classes . * A throw-away class that illustrates the five kinds of Java classes.
Read moreWhat are built in methods in Java?
In Java, predefined methods are the method that is already defined in the Java class libraries is known as predefined methods. It is also known as the standard library method or built-in method. We can directly use these methods just by calling them in the program at any point.
Read moreWhat is built in packages in Java?
Packages in java are used to avoid naming conflict and to control the access of class, interface, sub-classes, etc . A package can be defined as a group of similar types of classes, sub-classes, interfaces or enumerations, etc.
Read moreHow many built in classes are there in Java?
There are 5,000 or so classes built-in to Java, and programmers have written hundreds of thousands if not millions of their own.
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