JAVA Interfaces and Abstract Classes interface Test{ int p = 10; //line 1 public int q = 20; //line 2 public static int r = 30; //line 3 public static final int s = 40; //line 4}Which of the above line will give compilation error? 1 3 4 2 None of these 1 3 4 2 None of these ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes Determine output of the following code.interface A { }class C { }class D extends C { }class B extends D implements A { }public class Test extends Thread{ public static void main(String[] args){ B b = new B(); if (b instanceof A) System.out.println("b is an instance of A"); if (b instanceof C) System.out.println("b is an instance of C"); }} b is an instance of b is an instance of Nothing. b is an instance of A followed by b is an instance of b is an instance of b is an instance of Nothing. b is an instance of A followed by b is an instance of ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes Given the following piece of code:public class School{ public abstract double numberOfStudent();}which of the following statements is true? The keywords public and abstract cannot be used together. The method numberOfStudent() in class School must have a body. You must add a return statement in method numberOfStudent(). Class School must be defined abstract. The keywords public and abstract cannot be used together. The method numberOfStudent() in class School must have a body. You must add a return statement in method numberOfStudent(). Class School must be defined abstract. ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes Given the following piece of code:public interface Guard{ void doYourJob();}abstract public class Dog implements Guard{ }which of the following statements is correct? This code will compile without any errors. This code will not compile, because in the declaration of class Dog we must use the keyword extends instead of implements. This code will not compile, because class Dog must implement method doYourJob() from interface Guard. This code will not compile, because method doYourJob() in interface Guard must be defined abstract. This code will compile without any errors. This code will not compile, because in the declaration of class Dog we must use the keyword extends instead of implements. This code will not compile, because class Dog must implement method doYourJob() from interface Guard. This code will not compile, because method doYourJob() in interface Guard must be defined abstract. ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes What will be the output?1. public interface InfA{2. protected String getName();3. }public class Test implements InfA{ public String getName(){ return "test-name"; } public static void main (String[] args){ Test t = new Test(); System.out.println(t.getName()); }} test-name Compilation fails due to an error on lines 2 Compilation succeed but Runtime Exception None of these Compilation fails due to an error on lines 1 test-name Compilation fails due to an error on lines 2 Compilation succeed but Runtime Exception None of these Compilation fails due to an error on lines 1 ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes What will be the output when the following program is compiled and executed?abstract class TestAbstract{ String my_name; String myName(){ my_name = "Examveda"; return my_name; } abstract void display();}public class Test extends TestAbstract{ void display(){ String n = myName(); System.out.print("My name is "+ n); } public static void main(String args[]){ Test t = new Test(); t.display(); }} Compilation error occurs as the abstract class TestAbstract contains a non-abstract method. Program compiles but leads to runtime exception. None of these Program will compile and execute successfully and prints Compilation error as class can not be declared as abstract. Compilation error occurs as the abstract class TestAbstract contains a non-abstract method. Program compiles but leads to runtime exception. None of these Program will compile and execute successfully and prints Compilation error as class can not be declared as abstract. ANSWER DOWNLOAD EXAMIANS APP