CORE JAVA JAVA UTILS Interview Questions

Question: What is the Collections API?

Answer: The Collections API is a set of classes and interfaces that support operations on collections of objects

Question: What is the List interface?

Answer: The List interface provides support for ordered collections of objects.

Question: What is the Vector class?

Answer: The Vector class provides the capability to implement a growable array of objects

Question: What is an Iterator interface?

Answer: The Iterator interface is used to step through the elements of a Collection

Question: Which java.util classes and interfaces support event handling?

Answer: The EventObject class and the EventListener interface support event processing

Question: What is the GregorianCalendar class?

Answer: The GregorianCalendar provides support for traditional Western calendars

Question: What is the Locale class?

Answer: The Locale class is used to tailor program output to the conventions of a particular geographic, political, or cultural region

Question: What is the SimpleTimeZone class?

Answer: The SimpleTimeZone class provides support for a Gregorian calendar

Question: What is the Map interface?

Answer: The Map interface replaces the JDK 1.1 Dictionary class and is used associate keys with values

Question: What is the highest-level event class of the event-delegation model?

Answer: The java.util.EventObject class is the highest-level class in the event-delegation class hierarchy

Question: What is the Collection interface?

Answer: The Collection interface provides support for the implementation of a mathematical bag - an unordered collection of objects that may contain duplicates

Question: What is the Set interface?

Answer: The Set interface provides methods for accessing the elements of a finite mathematical set. Sets do not allow duplicate elements

Question: What is the purpose of the enableEvents() method?

Answer: The enableEvents() method is used to enable an event for a particular object. Normally, an event is enabled when a listener is added to an object for a particular event. The enableEvents() method is used by objects that handle events by overriding their event-dispatch methods.

Question: What is the ResourceBundle class?

Answer: The ResourceBundle class is used to store locale-specific resources that can be loaded by a program to tailor the program's appearance to the particular locale in which it is being run.