What is mean by method invoking in java?

Answer 1

method invoking refers to the action in which we call a Java method from within another java method or class.

Method invocation is analogous to a function call in procedural programming.

Answer 2

The virtual method invocation is a little tricky to explain. But I rather show you an example. Suppose you have a super class like this:

public class Super{

public int number = 1;

public String getColor(){

return "red";

}

}

and now we have a subclass of Super:

public class Sub extends Super{

public int number = 2;

public String getColor(){

return "blue";

}

}

All right, so what is the out put of the next program?

public static void main(String[] args){

Super supersub = new Sub(); //You can do this thanks polymorphism

System.out.println( supersub.getColor() + supersub.number );

}

The output could be "blue2" or maybe "red1". Nooo, the real input is "blue1" and this is due the virtual method invocation. Let me explain it better, you are using a variable of the 'Super' type, but you store there a 'Sub' object instead, the output must be either of the two that I predict before, but the java is capable of track in run time the real method implementation that you are using ("the one that return blue") but it can do the same with your object variable.

Answer 3

A Method definition in Java needs the below info:

• Method name
• Access specifier
• Return type
• Arguments

Ex:

public String getName(int empId) {}

here

• public is the access specifier
• String is the return type
• getName is the method name
• empId is the Argument

Answer 4

object.method();