[JAVA] What is a constructor?

What is a constructor?

A method that is executed when a class is instantiated, and is mainly used to initialize member variables of that class.

The constructor is a special method that is called when an instance is created, and it is possible to specify arguments in the same way as a normal method.

The call to the constructor is described as follows.

public class main class name{
public static void main(String[] args) {

//Instant generation
Class name variable name=new class name();

class class name{

//constructor(Executed when instantiating)
public class name(){
Initialization process, etc.

The constructor uses the new operator, and the method with the same class name is executed only once when the instance is created.

What is a constructor?

A constructor is a process that is executed when you create an instance of a class.

For example, if you want to create an instance of a class called SampleClass, code as follows.

SampleClass instanceA = new SampleClass();

The constructor is called by SampleClass (), which is written after new in this syntax.

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