5 Minute Java Test - Free Online 5 Minute Java Test in California, Bay Area, US

Welcome to the 5 Minute Java Test

Question:

Which of the given statements are correct for a method that overrides the following method:

public Set getSet(int a) {...}

Assume that Set is an interface and HashSet is a class that implements Set.

Select 3 option(s):

Its return type must be declared as Set

It can be abstract.

It may return HashSet.

It can declare any Exception in throws clause

It can declare any RuntimeException in throws clause

Question: Which of the following statements regarding java.io.File are true?

Select 3 option(s)

You cannot create a File object if a file or directory does not actually exist by that name.

Once created there is no way to change the file or directory that the File object represents.

You can create files in any directory using File class's API.

You can delete the actual file or directory represented by the File object using that object.

The same File object can be used to traverse between the directories.

Question: When a class whose members should be accessible only to members of that class is coded such a way that its members are accessible to other classes as well, this is called:-

Select 1 option(s):

weak coupling

high cohesion

strong coupling

strong typing

weak polymorphism

weak encapsulation

low cohesion

Question:

Given:-

public List<? extends Number> getList(){

*INSERT CODE HERE*

}

What can be inserted in the above code?

Select 3 option(s):

return new ArrayList< Number >();

return new ArrayList();

return new ArrayList< Integer >();

return new List< Number >();

return new ArrayList< Object >();

Question: Which of the following statements will compile without any error?

Select 4 option(s):

System.out.println("a"+63);

System.out.println('b'+new Integer(63))

System.out.println("a"+'b'+63);

String s = 63 + new Integer(10);

String s = 'b'+63+"a";

Question:

Encapsulation ensures that:-

Select 1 option(s):

classes designate certain methods to be abstract and let them be implemented by subclasses

a method that takes a class X object as a parameter can be passed an object of a subclass of X

classes are able to inherit functionality from other classes.

classes expose only certain fields and methods to other classes for access.