Introduction to Java & BlueJ

The Java programming language is an Object Oriented Programming language.

Encapsulation is the technique of binding both data and functions together.

A Class is a blueprint that defines data and functions common to all objects of a certain kind.

The smallest meaningful element of a Java program is called a Token.

Initialization is a process of assigning some initial value to a variable.

Polymorphism allows a function to behave differently for different objects.
True

Constants mean the fixed values that do not change during the execution of a program.
True

The main() function indicates that the execution of the Java program will begin from this point.
True

Every Java statement must end with a colon.
False

Inheritance is a feature using which an object in one class acquires the properties of another class.
True

While comparing two variables, their data types should not be the same.
False

Ritika has written a program in Java. After the successful compilation of her program, which option should she select to run it?

Kareena is writing a program in Java to calculate the average of three subjects. Which operators will she use for the same?

A .......... is a named location in the memory, which stores data temporarily.

What does OOP mean?

Which among the following feature is used to manage the complexity of the system?

A Java program is compiled into an intermediate language called ..........

The .......... works on a single variable or constant.

Which symbol is used to combine two or more items in a single line?

Define objects. Give a real life example to explain objects along with their attributes and behaviour.

What is class?

What do you understand by the term Polymorphism?

What are operators? Why do we need them?

What do you understand by the term Keyword?

What are variables? How are they different from Constants?

Write a program to print, "Welcome to the World of Computers".

public class KboatWelcome
{
    public static void main(String args[]) {
        System.out.println("Welcome to the World of Computers");
    }
}

Write a program to print your Name, Class, Roll_No, Marks and Age. Name this file, `MyProfile'.

public class MyProfile
{
    public static void main(String args[]) {
        System.out.println("Name: Sneha Nayak");
        System.out.println("Class: 8C");
        System.out.println("Roll No: 24");
        System.out.println("Marks: 87");
        System.out.println("Age: 15");
    }
}

Write a program to print your School name four times in separate lines.

public class KboatSchoolName
{
    public static void main(String args[]) {
        System.out.println("St. Francis' College");
        System.out.println("St. Francis' College");
        System.out.println("St. Francis' College");
        System.out.println("St. Francis' College");
    }
}

Write a program to find the sum and average of three numbers.

public class KboatSumAvg
{
    public static void computeSumAvg(int a, int b, int c) {
        System.out.println("The three numbers are " 
          + a + ", " + b + ", " + c );
        int sum = a + b + c;
        double avg = sum / 3.0;
        System.out.println("Sum = " + sum);
        System.out.println("Average = " + avg);
    }
}

Write a program to interchange the value of two numbers without using the third variable.

public class KboatSwap
{
    public static void swapNumbers(int a, int b) {
        System.out.println("The numbers are:");
        System.out.println("a=" + a + " b=" + b);
        a = a + b;
        b = a - b;
        a = a - b;
        System.out.println("The numbers after interchange:");
        System.out.println("a=" + a + " b=" + b);
    }
}

Write a program to calculate the compound interest.

public class KboatInterest
{
    public static void computeInterest(double p, double r, int t) {
        double amt = p * Math.pow(1 + (r / 100 ), t);
        double interest = amt - p;
        System.out.println("Compound Interest = " + interest);
    }
}

Write a program to calculate the tax for a taxable income of Rs. 4,10,000, if the tax rate is fixed at 3.2%.

public class KboatTax
{
    public static void main(String args[]) {
        int income = 410000;
        double rate = 3.2;
        double tax = income * rate / 100;
        System.out.println("Tax = " + tax);
    }
}

Create a program that will generate a bill at McDonald's for four vegetable burgers (@ Rs 45 per vegetable Burger) and three vegetable McPuffs (@ Rs 25 per vegetable McPuff). There is a special Independence Day discount of Rs 50 on the final bill amount.

public class KboatMcDBill
{
    public static void main(String args[]) {
        int vegBurgerCost = 4 * 45;
        int vegMcPuffCost = 3 * 25;
        int total = vegBurgerCost + vegMcPuffCost;
        int amt = total - 50;
        System.out.println("4 Vegetable Burgers @ 45 = " + vegBurgerCost);
        System.out.println("3 Vegetable McPuffs @ 25 = " + vegMcPuffCost);
        System.out.println("Total = " + total);
        System.out.println("Discount = 50");
        System.out.println("Final Bill = " + amt);
    }
}