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Understanding Constructors in Java: A Simple Guide with Examples and Analogies

  What is a Constructor in Java? In Java, a constructor is a special type of method that is used to initialize objects. When you create an object of a class, the constructor is called automatically. Its main job is to set the initial values of the object’s properties or perform any setup that the object needs before it can be used. Why Do We Need Constructors? You need constructors because: Initialization : Constructors are responsible for initializing an object when it is created. Automatic Execution : A constructor is automatically called when an object is created, so you don’t have to manually initialize every property. Simplifying Object Creation : It simplifies object creation by providing default values or custom initialization. Where Do Constructors Fit in Java? Constructors fit within a class. They are used whenever a new object of that class is created, and they allow the object to be initialized. Constructors must have the same name as the class, and they don't have a re...
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Procedure to Run the program with different class name and file name in java.

If your Java file is named `hw.java` and the public class inside it is named `HelloWorld`, you can still compile and run it. Here's how you can do it:

1. Compile the Java File:


   javac hw.java


   This will generate a `HelloWorld.class` file.


2. Run the Program:


   To run the compiled Java program, use the `java` command followed by the public class name `HelloWorld`:


   java HelloWorld


This approach works because Java uses the public class name to determine the entry point for execution, not the filename. So even though the filename (`hw.java`) doesn't match the public class name (`HelloWorld`), you can still run the program using the public class name.


OR 


you can directly run the program with the following command 

            java hw.java 

It will compile and run the program in one hit. 

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