Parameters,Arguments & Constructor

 Parameters and Arguments

Today we're here to discuss about parameters and arguments in JAVA.




Let's look at it by studying the above example.

  • Parameter is there to keep inputs and outputs.
  • Information can be passed to a method by using parameter list.
  • Parameters act as variables inside a method.
  • We can add many Parameters by seperating with commas.
  • When a parameter is passed to a method,it is called an argument.
  • Arguments in JAVA are actually the values that are passed to the variables in a method.
  • Return type is used to return the output.
  • In JAVA, the default return type is "void".It can return any data type or String value.
  • And also String or any data type can be used as the return type.But we must use the "return" keyword inside the method.
eg:- 1) int area (int x,int y){
        int z=x*y;
        return z;
        System.out.print(z);
        }
        area (7,13);

     2) String aBC (String a,int b){
        return "hello",8 ;
        }
        aBC ("hello",8);

Constructor

A Constructor is a method that is created by using the name of the class,called only when creating the object and that haven't a return type.
Constructor is a special method that is used in JAVA programming.
We cannot always run the constructor,it can be call when creating an object.
         eg:- class Example {
               Example(){
               }
              }
Constructor calling

  • When an application is working,the constructor will run first.
  • We can code the things that we want to be done at first,inside the Constructor.
  • Although it haven't a return type,it can pass values and use parameters and arguments in the constructor.
At last we can simply identify  4 components that should included in a JAVA code.
Let's meet again in a new article!
Until then good bye!
 

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