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DIFFERENCE BETWEEN CONSTRUCTOR AND METHOD

Constructor Method
It is used to initialize the instance variables of It is used to execute the Java code which performs
the class. a specific job.

It can be invoked only once at the time of It can be invoked anytime as and when required.
creating the object.
It has the same name as that of the class. It has the different name from the class.

It does not have a return type. It has a return type.
It always public. It may be public or private.

Quick Quiz

1. What is the purpose of the switch statement in Java?

a. To replace the long if…else ladder and simplify the code

b. To allow the execution of multiple conditions without stopping

2. How can you use a predefined method like CharAt() in Java?

a. By creating an object of the class that contains the method

b. By defining your own method with the same name

Recap

Java is an object-oriented programming language. It was developed by James Gosling and his team
including Mike Sheridan and Patrick Naughton, at Sun Microsystems in 1995.
A data type is an attribute of data which tells the compiler or interpreter how the programmer
intends to use the data or value.
A variable is a name given to a space in computer memory to store a value. In other words, it is a
reference to a memory location where data is held.
Conditional statements allow us to change the default flow of a program.
Looping statements are the control flow statements that allow us to repeatedly execute a set of
statements for a given number of times.
Object-Oriented Programming is another way of programming. It follows a Bottom-Up approach
and emphasises more on data rather than functions.
Methods are necessary to perform operations on the data members of a class.
A programmer can define a function anywhere inside a class after declaring the data members.
A constructor is a type of special member method with same name as of class.

Java Programming 123