Can you have multiple objects in Java?
We can have multiple classes in different Java files or single Java file. If you define multiple classes in a single Java source file, it is a good idea to save the file name with the class name which has main() method.
Can multiple objects have the same name in Java?
The two constructors with different parameters are simply used to initialize the fields in the object. It is possible to have multiple methods and multiple constructors with the same name. This process of using same names for multiple methods or constructors with different signature is referred to as OVERLOADING.
Can a class have multiple objects?
A class can be thought of as a “type”, with the objects being a “variable” of that type. Multiple objects, or instances of a class can be created in a single HLU program, just as you declare multiple variables of the same type in any program.
Is it possible to create multiple objects from the same constructor?
You can declare multiple variables on the same line. However, it is generally a good idea to declare no more than three variables on the same line. Each variable will then require it’s own instantiation, which could either be to three different objects of the same type or to the same object.
Is overriding possible in Java?
Java Overriding Rules Both the superclass and the subclass must have the same method name, the same return type and the same parameter list. We cannot override the method declared as final and static . We should always override abstract methods of the superclass (will be discussed in later tutorials).
Can class and object have same name?
Yes, the constructor should always have the same name as the class. It does not have a return type and its name is same as the class name. Mostly it is used to instantiate the instance variables of a class. If the programmer doesn’t write a constructor the compiler writes a constructors on his behalf.
Why do we create one or more objects of class in Java?
Using Multiple Classes You can also create an object of a class and access it in another class. This is often used for better organization of classes (one class has all the attributes and methods, while the other class holds the main() method (code to be executed)).
What is the difference between classes and objects in Java?
Java Questions Answers A class is a blueprint from which you can create the instance, i.e., objects. An object is the instance of the class, which helps programmers to use variables and methods from inside the class.
Can a class have multiple constructors in Java?
The technique of having two (or more) constructors in a class is known as constructor overloading. A class can have multiple constructors that differ in the number and/or type of their parameters. It’s not, however, possible to have two constructors with the exact same parameters.
Can we add different data types in List?
You can use Object for storing any type of value for e.g. int, float, String, class objects, or any other java objects, since it is the root of all the class. For e.g. main function code, which creates the new person object, int, float, and string type, and then is added to the List, and iterated using for loop.
How to have two classes in a single Java program?
A single Java program contains two or more classes, it is possible in two ways in Java. In the below example, the java program contains two classes, one class name is Computer and another is Laptop. Both classes have their own constructors and a method. In the main method, we can create an object of two classes and call their methods.
How many public classes can you have in a java file?
You can use at most one public class per one java file (COMPILATION UNIT) and unlimited number of separate package-private classes. Compilation unit must named as public class is. You also can have in your public class the unlimited number of inner classes and static nested classes.
How many classes can be created in a single file?
In short, the number of .class files created will be equal to the number of classes in the code. We can create as many classes as we want but writing many classes in a single file is not recommended as it makes code difficult to read rather we can create a single file for every class. Constructor of Computer class.
What happens if you have multiple classes in a file?
However, there are some surprising problems that can happen if you have multiple classes in a file. Basically, you can get into trouble by (accidentally or otherwise) defining multiple classes with the same name in the same package. If you’re just a beginner, it might be hard to imagine what I’m going on about.