Quiz on Java keywords

Which form of an association is highly dependent on another entity?

class company {

public void method(String a )

{

return a;

}

}

class Worker {

public void method( String b )

{

return b;

}

}

class Main {

public static void main ( String args [ ] )

{

Company c = new Company();

Worker w = new Worker();

String name = c.method(“DataFlair”);

String text = w.method(“Raj”);

System.out.println(name+text);

}

}

What is the output of the program ?

class Product {

public void store ( String name )

{

String item = this.name;

}

}

class Price {

public void store ( double value )

{

double val = this.value;

}

}

class Store {

public static void main ( String args [ ] )

{

Product p1 = new Product(“Rice”);

Product p2 = new Product(‘Wheat”);

Product p3 = new Product(“Dhal”);

Price m1 = new Price(“80”);

Price m2 = new Price(“70”);

Price m3 = new Price(“50”);

System.out.println(“Product is “ + p1 + “Price is “ + m1 );

System.out.println(“Product is “ + p2 + “Price is “ + m2 );

System.out.println(“Product is “ + p3 + “Price is “ + m3 );

}

}

What is the output of the program ?

 Which of the following is an unidirectional way of association ?

class Demo {

public int function ( String a )

{

String text = this.a;

}

}

class Sample {

public void function( String b )

{

String message = this.b;

}

}

class Main {

public static void main ( String args [ ] )

{

Demo d = new Demo(“DataFlair”);

Sample s = new Sample(“Webservices”);

System.out.println( d + s );

}

}

What is the output of the program ?

class Students {

String name;

long rollno;

void display ( String a , long b )

{

name = this.a;

rollno = this.b;

}

}

class Department {

String dep;

void display ( String c )

{

dep = this.c;

}

}

class college {

public static void main ( String args [ ] )

{

Student s1 = new Student(“David” , 14 );

Student s2 = new Student(“Rohit” , 55);

Student s3 = new Student(“Shikar”, 40 );

List <String,int> list = new List();

l.add(s1);

l.add(s2);

l.add(s3);

System.out.println(l.size());

}

}

What is the output of the program ?

What will happen if one entity is deleted in a composition association ?

class Student {

String name;

Student( String a )

{

name = this.a;

}

}

class Subject {

String sub;

Subject ( String b )

{

sub = this.b;

}

}

class Main {

public static void main ( String args [ ] )

{

Student obj1 = new Student(“Ravi”);

Subject s1 = new Subject(“Maths”);

Subject s2 = new Subject(“Science”);

System.out.println( obj1 + “learns “ + s1 + “and also “ + s2 );

}

}

What is the output of the program ?

class BasicSalary {

private double salary;

public void getSalary( double amount )

{

return amount;

}

public void setSalary( double amount)

{

salary = this.amount;

}

}

class Allowances {

private double pay ;

public void getPay( double allow )

{

return allow;

}

public void setPay ( double allow )

{

pay = this.allow;

}

}

class NetPay {

public static void main ( String args [ ] )

{

BasicSalary b = new Basic Salary(10000);

Allowances a = new Allowances(2000);

System.out.println(‘Net pay is “ + ( b + a ) );

}

}

What is the output of the program ?

What is the type of relation that composition associations have ?

 class Employee {

String empname;

Employee( String empname )

{

return empname;

}

}

class Salary {

float salary;

Salary ( String salary )

{

return salary;

}

}

class Company {

public static void main ( String args [ ] )

{

Employee e1 = new Employee(“Kumar”);

Employee e2 = new Employee(“Thakur”);

Employee e3 = new Employee(“Singh”);

Salary s1 = new Salary(15000);

Salary s2 = new Salary(13000);

Salary s3 = new Salary(10000);

HashTable<Float , String > list = new HashTable();

list.add(e1,s1);

list.add(e2.s2);

list.add(e3,s3);

System.out.println(list);

}

}

What will be the output of the program ?

class Sample {

public void display()

{

System.out.println(“Sample class is needed”);

}

}

class Concept {

Private Sample sample;

Concept(Sample sample)

{

this.sample = sample:

}

public void display()

{

sample.display();

System.out.println(“Concept is explained”);

}

}

class Main {

public static void main ( String args [ ] )

{

Sample s = new Sample();

Concept c = new Concept();

c.display();

}

}

What is the output of the program ?

Which technique is highly employed while using associations ?

class Associations {

public void print(String a )

{

return a;

}

}

class Aggregation {

public void print(String b)

{

return b;

}

}

class Composition {

public void print( String c )

{

return c;

}

}

class Main {

public static void main ( String args [ ] )

{

Associations a1 = new Associations(“Connection between two class objects”);

Aggregations a2 = new Aggregations(“Is-A relationship association”);

Composition a3 = new Composition (“Has-A relationship association”);

a2.print();

}

}

What is the output of the program ?

 class Vegetables {

public void veg ( String vegetable )

{

return vegetable;

}

}

class Fruits { 

public void fru ( String fruit )

{

return fruit;

}

}

class Consumable {

public static void main ( String args [ ] )

{

Vegetables v1 = new Vegetables(“Tomato”);

Vegetable v2 = new Vegetables(“Beetroot”);

Vegetable v3 = new Vegetables(“Potato”):

Fruits f1 = new Fruits(“Apple”);

Fruits f2 = new Fruits(“Orange”);

List<String> list = new List();

list.add(v1);

list.add(v2);

list.add(v3);

list.add(f1);

list.add(f2);

if(list.size==5)

{

System.out.println(“Both Vegetables and fruits are added”);

} else {

System.out.println(“Only one is added”);

}

}

What is the output of the program ?