JAVA Interfaces and Abstract Classes In Java, declaring a class abstract is useful When it doesn't make sense to have objects of that class. When it makes sense to have objects of that class. When default implementations of some methods are not desirable. To prevent developers from further extending the class. 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. When default implementations of some methods are not desirable. To prevent developers from further extending the class. To force developers to extend the class not to use its capabilities. ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes Which of the following declares an abstract method in an abstract Java class? public void abstract Method(); public abstract void method(); public abstract void method() {} public void method() {} public abstract method(); public void abstract Method(); public abstract void method(); public abstract void method() {} public void method() {} public abstract method(); 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 2 and 3 1 and 2 3 and 4 1 and 3 2 and 4 2 and 3 1 and 2 3 and 4 1 and 3 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. None of these Program compiles but leads to runtime exception. 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. None of these Program compiles but leads to runtime exception. Program will compile and execute successfully and prints Compilation error as class can not be declared as abstract. 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) }} 4 and 5 1 and 2 2 and 3 3 and 4 1 and 3 4 and 5 1 and 2 2 and 3 3 and 4 1 and 3 ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes Which of the following statements regarding abstract classes are true? An abstract class can be extended. A subclass can override a concrete method in a superclass to declare it abstract. All of these An abstract class can be used as a data type. A subclass of a non-abstract superclass can be abstract. An abstract class can be extended. A subclass can override a concrete method in a superclass to declare it abstract. All of these An abstract class can be used as a data type. A subclass of a non-abstract superclass can be abstract. ANSWER DOWNLOAD EXAMIANS APP
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