Java Online Quiz January 29, 2021 Below are the instructions for this quiz: Time Limit for this Quiz is 30 minutes This quiz has 20 questions Multiple choice questions Multiple attempts are allowed Enter your Email: 1. [ Java ]Which Java declaration will return syntax error?Double[] var = {1.0,2.0,3.0,4.0};List>var;List var;float var = 4.3f;2. [ Java ]What is the difference between Vector and ArrayList?ArrayList is synchronized but Vector is notVector is synchronized but ArrayList is notArrayList uses Array as its data structure but Vector used vectorVector is dynamically resized but ArrayList is manually resized3. [ Java ]Create a set of strings and add the string "def" three times to this set, then remove an "def" string. What will happen when size() method is called on this set?returns 2returns 0IllegalStateExceptioncompile time error4. [ Java ]What is @Override annotation?It stops overriding the methodIt forces the subclass to override the methodIt makes the method virtualIt causes the compiler to check the method exists in a superclass5. [ Java ]Which of the following code snippets will compile?None of the snippets will compileList a = new ArrayList();List a = new ArrayList();List a = new ArrayList();6. [ Java ]What is correct variable type for the result?... variable = 5 + 0.11;integerlongfloatdouble7. [ Java ]When is an object's finalize method called?When the object needs to release any resource it holdsWhen last reference to object is destroyed or out of scopeRight before the object is garbage collectedWhen System.gc() is called8. [ Java ]Which of the following code snippets would compile successfully?int i = 1L + 2L;int i = 1L + 2;float = 3.14;long l = 1L + 2;9. [ Java ]In the following code. Who has access to member num?package car;public class Audi { int num;}Only class Audi and subclasses of Audi within any packageOnly class AudiClass Audi, subclass of Audi defined in package car, and other classes in package carClass Audi, subclasses of Audi defined in any package, and other classes in package car10. [ Java ]What happens when we try to add the same element twice to a Set?Compile time errorElement is not added and add() method returns falseElement is added successfullyIllegalStateException11. [ Java ]What is the output for the below code?public class Test{ public static void main(String[] args){ Integer i = Integer.valueOf("1"); if(i.toString()=="1") System.out.println("Equal"); else System.out.println("Not Equal"); }}Syntax ErrorEqualNot EqualCompile-Time Error12. [ Java ]Which Java class provides variables local to each thread?RunnableLocalThreadThreadThreadLocal13. [ Java ]Which of the following statements is true?An abstract class can have both abstract and non-abstract methodsAn abstract class can declare a static abstract methodAll methods in an Abstract class need to be abstractAn abstract class can have abstract private methods14. [ Java ]Which one these is a valid keyword in Java?unsignedstringinterfaceFloat15. [ Java ]Which of the following declaration is correct?class A implements InterfaceA extends ClassAclass A implements InterfaceA, InterfaceB extends ClassAclass A extends ClassA, ClassB implements InterfaceA, InterfaceBclass A extends ClassB implements InterfaceA, InterfaceB16. [ Java ]What modifier is used to provide access to a method within the class and all the extending classes?protecteddefaultprivatepublic17. [ Java ]What is the command to run a JAR file application?$ java -jar application.jar$ java -start application.jar$ jar -java application.jar$ java -run application.jar18. [ Java ]What is the output of the following class?public class Test{ public Test() { int x = 5; return x; } public static void main(String[] args){ System.out.println(new Test()); }}run time errorcompile time error5x19. [ Java ]There is a class with private constructors only. How can we provide a way to create instance of this class?class will not compileThere is no way to create instance of this class.Create a static method within the class that will call one of the private contructorsExtend this class and make contructor public20. [ Java ]Which member of an abstract class can be abstract?Protected methodsPrivate methodsStatic methodsConstructorsPlease fill in the comment box below.
