Question 1

Question 1What is a method? Explain the various parts of a method.

Accepted Answer

A method is a named block of code within a class. It executes a defined set of instructions when called from another part of the program. The different parts of the method are access-modifier, type, method-name, parameter-list and method-body.

Question 2

Question 2How do you define and invoke a method?

Accepted Answer

The syntax of a method definition is:[access-modifier] type method-name (parameter-list){    method-body;}To invoke a method, write the name of the method and specify the value of arguments of its parameter list. Below example shows the definition and invocation of a method:public class DisplayMessageDemo {

public void DisplayMessage() {
        System.out.println("Hello World!");
    }

public void MyMessage() {
        DisplayMessage();
    }
}

Question 3

Question 3Explain the role of return statement in a method?

Accepted Answer

Return statement sends back the value given to it from the called method to the caller method. It also transfers the program control back to the caller method from the called method.

Question 4

Question 4What does void signify in the method prototype?

Accepted Answer

void in method prototype means that the method does not return any value.

Question 5

Question 5Explain the difference between actual and formal parameters with one example of each.

Accepted Answer

The parameters that appear in the method definition are called formal or dummy parameters whereas the parameters that appear in the method call are called actual parameters. Example:public class FindSquareDemo {

public int FindSquare(int x) {
        int result;
        result = x * x;
        return result;
    }

public void MyFindSquare() {
        int num = 4;
        int myResult;
        myResult = FindSquare(num);
        System.out.println("Square of " + num + " is " + myResult);
    }
}Here, variable x in the definition of FindSquare is formal parameter and variable num in the method call of FindSquare is actual parameter.

Question 6

Question 6Explain static and non-static methods.

Accepted Answer

Static methods are created with static keyword in their method prototype as shown below:public static return-type method-name(parameter-list)
{
    Method-body
}
Static methods can be called directly using class name but they can't access instance variables and non-static methods of the class.The non-static methods are created without the static keyword in their method prototype as shown below:public return-type method-name(parameter-list)
{
    Method-body
}
An instance of the class is required to call non-static methods.

Question 7

Question 7Explain the scope of variables in Java

Accepted Answer

Scope of the variable determines in which parts of the program the variable is accessible. It is of the following types:Local Variables — The variables declared inside a method or block are called local variables. The scope of local variables is limited to the method or the block they are declared in.Parameter Variables — The variables used as arguments in the method prototype are called parameter variables. Their scope is limited to the method where they are being used.Instance Variables (non-static variable) — The member variables that store the state of an object are known as instance variables.Class Variables (static variable) — A variable declared in a class with the static modifier is called a class variable.

Question 8

Question 8Methods reside in a class in Java.True

Accepted Answer

Answer: True

Question 9

Question 9The scope of a local variable is limited to the method or the block it is declared in.True

Accepted Answer

Answer: True

Question 10

Question 10The keyword static makes a variable a class variable.True

Accepted Answer

Answer: True

Working with Methods

Assignment Questions

State whether the given statements are True or False