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(); 3 and 4 1 and 2 2 and 3 2 and 4 1 and 3 3 and 4 1 and 2 2 and 3 2 and 4 1 and 3 ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes Which of the following class definitions defines a legal abstract class? class A { abstract void unfinished(); } public class abstract A { abstract void unfinished(); } abstract class A { abstract void unfinished(); } class A { abstract void unfinished() { } } class A { abstract void unfinished(); } public class abstract A { abstract void unfinished(); } abstract class A { abstract void unfinished(); } class A { abstract void unfinished() { } } 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) }} 1 and 2 1 and 3 4 and 5 3 and 4 2 and 3 1 and 2 1 and 3 4 and 5 3 and 4 2 and 3 ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes Runnable is a _____ . class method abstract class vaiable interface class method abstract class vaiable interface 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. } Compilation fails due to an error on line 8 A Compilation fails due to an error on line 3 None of these null Compilation fails due to an error on line 8 A Compilation fails due to an error on line 3 None of these null 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? Class School must be defined abstract. The method numberOfStudent() in class School must have a body. The keywords public and abstract cannot be used together. You must add a return statement in method numberOfStudent(). Class School must be defined abstract. The method numberOfStudent() in class School must have a body. The keywords public and abstract cannot be used together. You must add a return statement in method numberOfStudent(). ANSWER DOWNLOAD EXAMIANS APP
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