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(); 1 and 2 2 and 3 3 and 4 1 and 3 2 and 4 1 and 2 2 and 3 3 and 4 1 and 3 2 and 4 ANSWER DOWNLOAD EXAMIANS APP
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? 2 3 1 4 None of these 2 3 1 4 None of these ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes In Java, declaring a class abstract is useful To force developers to extend the class not to use its capabilities. When it doesn't make sense to have objects of that class. When it makes sense to have objects of that class. To prevent developers from further extending the 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. When it makes sense to have objects of that class. To prevent developers from further extending the class. When default implementations of some methods are not desirable. ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes Which of the following statements regarding abstract classes are true? An abstract class can be used as a data type. An abstract class can be extended. All of these A subclass of a non-abstract superclass can be abstract. A subclass can override a concrete method in a superclass to declare it abstract. An abstract class can be used as a data type. An abstract class can be extended. All of these A subclass of a non-abstract superclass can be abstract. A subclass can override a concrete method in a superclass to declare it abstract. ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes Runnable is a _____ . interface vaiable class abstract class method interface vaiable class abstract class method 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 will print Class Two method compiles fine but print nothing will print Class One method Compilation Error None of these will print Class Two method compiles fine but print nothing will print Class One method Compilation Error ANSWER DOWNLOAD EXAMIANS APP
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