JAVA Interfaces and Abstract Classes Which of the following class definitions defines a legal abstract class? class A { abstract void unfinished() { } } abstract class A { abstract void unfinished(); } class A { abstract void unfinished(); } public class abstract A { abstract void unfinished(); } class A { abstract void unfinished() { } } abstract class A { abstract void unfinished(); } class A { abstract void unfinished(); } public class abstract A { abstract void unfinished(); } ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes What is the output for the below code ?interface A{ public void printValue();}1. public class Test{2. public static void main (String[] args){3. A a1 = new A(){4. public void printValue(){5. System.out.println("A");6. }7. };8. a1.printValue();9. }10. } A Compilation fails due to an error on line 8 null Compilation fails due to an error on line 3 None of these A Compilation fails due to an error on line 8 null Compilation fails due to an error on line 3 None of these ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes Suppose A is an abstract class, B is a concrete subclass of A, and both A and B have a default constructor. Which of the following is correct?1. A a = new A();2. A a = new B();3. B b = new A();4. B b = new B(); 2 and 3 2 and 4 1 and 3 1 and 2 3 and 4 2 and 3 2 and 4 1 and 3 1 and 2 3 and 4 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()); }} Compilation succeed but Runtime Exception Compilation fails due to an error on lines 1 None of these test-name Compilation fails due to an error on lines 2 Compilation succeed but Runtime Exception Compilation fails due to an error on lines 1 None of these test-name Compilation fails due to an error on lines 2 ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes What will be the output?interface A{public void method();}class One{public void method(){System.out.println("Class One method");}}class Two extends One implements A{public void method(){System.out.println("Class Two method");}}public class Test extends Two{public static void main(String[] args){A a = new Two();a.method();}} None of these compiles fine but print nothing Compilation Error will print Class One method will print Class Two method None of these compiles fine but print nothing Compilation Error will print Class One method will print Class Two method ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes In Java, declaring a class abstract is useful When default implementations of some methods are not desirable. To force developers to extend the class not to use its capabilities. When it doesn't make sense to have objects of that class. To prevent developers from further extending the class. When it makes sense to have objects of that class. When default implementations of some methods are not desirable. To force developers to extend the class not to use its capabilities. When it doesn't make sense to have objects of that class. To prevent developers from further extending the class. When it makes sense to have objects of that class. ANSWER DOWNLOAD EXAMIANS APP