Classes are considered the core of Java programming languages. Classes are the basic building block of an object-oriented programming language. Java language is an object-oriented programming language. Any concept that has to be implemented in the java language must be enclosed within a class. The basics of object-oriented programming languages are methods and classes. Java classes include classes and methods.
What is Method?
A collective set of codes is defined as methods. This set is responsible for the perform specific tasks. These are addressed by names. It can be called at any time to return the result. The return type of a method is void if the method is unable to return the value. In simple terms, we can explain methods as a set of instructions and when it is called, the set of instructions within the method is executed. Methods are referred to in their name. A method is called at any point of doing a program, when the program is completed the method will return to the place of the program where it is called. Methods help in saving time. It can be used for the repetition of codes of certain sections. Methods are of great help so that the users don’t need to retype the code. Every method in java is a part of a class. Methods have six components. They are :
- Return type
- Method name
- Method Body
Methods are of different types. If a method is already defined in a java class, then it is called a predefined method. It is also called a built-in method. Another one is the user-defined method, where the user is writing the method.
What is Constructor?
As the name suggests it is used to construct something in Java programming. It is a specialised method used to initialize the objects. When an object class is created, the constructor is called. It is mainly used to set values and initialize objects. Constructors are a block of codes. They are similar to methods. At the instance of the creation of a class, a constructor is called. When the constructor is called, the memory for the object is allocated. Constructors are a special type of method. At least one constructor is called when an object is created using the new () keyword. At this time the default constructor will be called. The name of the constructors in a class must bear the same name of the class in which it resides. In java, the constructor cannot be abstract, final, static, or synchronized. For controlling the access to a constructor, Access modifiers are used. There are two main constructors in Java. They are:
- No argument constructor
- Parameterized constructor
If the user doesn’t define a constructor in a class, the compiler will create a default constructor i.e with no arguments is called a no-argument constructor. These constructors do not have any parameters. If a constructor has parameters, then it is called a parameterized constructor. If we have our values and need to initialize fields of a class with that, the parameterized constructor is used.
Difference Between Constructors and Methods
We have seen what is methods and what is constructors. Both these are essential components in Object Oriented Programming languages. So let us look into the difference between the constructors and methods.
The constructor is similar to the method. The only exception is the return type. Methods have the feature of return. Constructors are specialized methods that are used for initializing objects. Methods are a set of codes that can be called at any time of programming and will return after the task is completed.
Constructors aim at creating an instance in class. An object in memory is also created with this. The purpose of the method is to group a block of statements to perform the task.
The name of the class and the constructor are the same where it is called. But methods are named differently from the class
Constructors are not inherited by the subclass whereas metaphors are called from the subclass.
When a new keyword is created, constructors are called. They are called directly. Methods are also called directly, but there is no need of creating new keywords. They start their operations in the existing thread.
Methods and Constructors are key factors that are used in Object-Oriented Programming languages. They are similar in almost all aspects. Their difference lies in the return type. Methods can return after performing tasks.