Question

Java please answer A to I please dont type the answer on paper please use the computer

A.   Explain why alpha cannot be accessed by other members of its class.
B.   In the program, how can you determine the type of access modifier?
C.   Describe the differences and similarities of beta and gamma in program, within the context of access specifiers and class member accessibility.

// Public vs private access. class Myclass { private int alpha; // private access public int beta; // public access int gamma; // default access /* Methods to access alpha. It is OK for a member of a class to access a private member of the same class. */ void setAlpha (int a) { alpha = a; int getAlpha() { return alpha; class AccessDemo { public static void main(String args[]) { MyClass ob = new MyClass(); /* Access to alpha is allowed only through its accessor methods. */ ob.setAlpha (-99); System.out.println("ob.alpha is " + ob.getAlpha()); // You cannot access alpha like this: ob.alpha = 10; // Wrong! alpha is private! + - Wrong-alpha is private! // These are OK because beta and gamma are public. ob.beta = 88; + OK because these are public. ob.gamma = 99;

D.   Explain how objects, a and b, are passed to the method.
E.    Why primitive type cannot be used in the objects of this program?
F.   Explain how the call or changes of objects, a and b, impact the output of the program.

G.   How does void ovlDemo() and int ovlDemo() impact the output of the program?
H.   What will the program output when the method is overloaded with the same type and numbers of parameters?

I.Applying the concept of method overloading, create, compile and run a Java program that calculates and displays the result for each overload:

Given int P = 30, double Q = 50.00, float R = 70.5

• First overload: return P + 1/3P
• Second overload: return Q + 1/2Q
• Third overload: return R + 1/4R

Answer 1

A) A member variable or field declared as private can only be accessed by within the class or through its methods,if a object for that class is declared inside another class then only fields declared as public can be accessed.

B)Access modifiers are specified along with the member variables at the time of its declaration.For example public int beta is declared in class MyClass ,so public is the access modifier here.

C)The access specifier used for beta is public and for gamma nothing is specified so default access specifier is considered.As beta is declared as public it can be accessed by any class in the program without any errors,but as gamma is declared with a default access specifier thus it can only be access by class present in the same package and any class outside the package cannot access gamma results in a compilation error.

D)Objects a and b are passed through pass-by reference.Although in Java pass-by-value is used for non-primitive type such as an object pass-by-reference is used.Thus any changes made to the object will reflect in the main object as long as we don't make the object to point to any other address.

E)Question is not clear

F)As i told earlier any changes to copy of reference of the objects inside the method will result in changes to the object itself.Thus ob.a=35(i.e 15+20) and ob.b=-20

G)void ovlDemo() does not return any data but whereas int ovlDemo() return a data of type int provided the two numbers have different signature i.e the parameters should either have different datatype or the number of parameters should be different.

H) A method overloaded should always have different number of parameters or different type of parameters.If methods with same number and same type of of parameters are overloaded then compilation error will be generated.The return type of the method is not taken into consideration while differentiating methods

I)class overload{

double cal(int a)

{ return a+(1/(3a));

}

double cal(double a)

{return a+(1/(2a));

}

double cal(float a)

{ return a+(1/(4a));

}

}

class OverloadDemo{

public static void main(String args[]){

overload ob=new overload();

int P=30 ;double Q=50.00 ;float R=70.5

double ans;

ans=ob.cal(P);

system.out.println("Result of first overload is "+ans);

ans=ob.cal(Q);

system.out.println("Result of second overload is "+ans);

ans=ob.cal(R);

system.out.println("Result of third overload is "+ans);

}

}