Java Quiz-3

Which of the following Set interface depends on the compareTo() method for ordering and detecting duplicates?

• HashSet

• TreeSet

• LinkedHashSet

• None

What will be the output of the code given below?

• [12, 13]

• [13, 14]

• compilation error: parameter needs to be passed to remove() method

• [12, 13, 14]

Choose TWO correct options.

• order.add("Pizza");

• order.add('Pizza');

• 
  order.add(123);

• 
  order.add(null);

What will happen if two threads try to access the same synchronized method at the same time?

• Both threads will execute the method simultaneously
  

• One thread will wait while the other executes

• Both threads will be blocked

• An exception will be thrown

Which method is used to pause a thread for a specified time?

• wait()

• sleep()
  

• pause()

• suspend()

Which of the following methods are used for interthread communication in Java?

• sleep(), join(), yield()

• run(), start(), stop()

• pause(), resume(), restart()

• wait(), notify(), notifyAll()

What is returned by the peek() method of a Queue?

• The head element is removed.

• The head element is retrieved without removing it

• The tail element is removed.

• The Last element is removed

Which data structure does a TreeSet use internally?

• LinkedList

• Hash Table

• Red-Black Tree

• Binary Heap