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. A subclass can override a concrete method in a superclass to declare it abstract. An abstract class can be extended. A subclass of a non-abstract superclass can be abstract. All of these An abstract class can be used as a data type. A subclass can override a concrete method in a superclass to declare it abstract. An abstract class can be extended. A subclass of a non-abstract superclass can be abstract. All of these 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. Class School must be defined abstract. You must add a return statement in method numberOfStudent(). The method numberOfStudent() in class School must have a body. The keywords public and abstract cannot be used together. Class School must be defined abstract. You must add a return statement in method numberOfStudent(). The method numberOfStudent() in class School must have a body. 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 4 3 and 4 2 and 3 1 and 3 1 and 2 2 and 4 3 and 4 2 and 3 1 and 3 1 and 2 ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes interface Base{ boolean m1 (); byte m2(short s);}which two code fragments will compile?1. interface Base2 implements Base {}2. abstract class Class2 extends Base { public boolean m1(){ return true; }}3. abstract class Class2 implements Base {}4. abstract class Class2 implements Base { public boolean m1(){ return (7 > 4); }}5. abstract class Class2 implements Base { protected boolean m1(){ return (5 > 7) }} 3 and 4 1 and 2 1 and 3 2 and 3 4 and 5 3 and 4 1 and 2 1 and 3 2 and 3 4 and 5 ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes What will happen after compiling this program code?abstract class MyClass{ //line 1 private int a, b; public void call(int a, int b){ this.a = a; this.b = b; System.out.print(a+b); }}public class Test{ public static void main(String args[]){ MyClass m = new MyClass(); //line 2 m.call(12,25); }} Runtime error Compilation error due to line 2 Successful run and print 37 Compilation error due to line 1 None of these Runtime error Compilation error due to line 2 Successful run and print 37 Compilation error due to line 1 None of these 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 as class can not be declared as abstract. Program compiles but leads to runtime exception. None of these Program will compile and execute successfully and prints Compilation error occurs as the abstract class TestAbstract contains a non-abstract method. Compilation error as class can not be declared as abstract. Program compiles but leads to runtime exception. None of these Program will compile and execute successfully and prints Compilation error occurs as the abstract class TestAbstract contains a non-abstract method. ANSWER DOWNLOAD EXAMIANS APP
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