Technical interview questions and answers are essential for any Java Interview because Java is one of the most widely used programming languages in software development. Companies expect candidates to know OOP concepts, multithreading, exceptions, JDBC, collections, and real-time coding questions. Java interviews are commonly part of campus placements and software development roles in companies such as TCS, Infosys, Wipro, Cognizant, and Accenture. For freshers and job seekers, understanding Java concepts clearly makes it easier to clear technical rounds, online coding tests, and project discussions. This guide includes the most important and frequently asked Java interview questions with detailed explanations to help you prepare efficiently. These questions will help you gain confidence during software developer interviews and competitive placement tests.
Java professionals should deepen their expertise through J2EE development concepts and data structures fundamentals
Showing 10 of 301 questions
141. What modifiers may be used with an inner class that is a member of an outer class?
A (non-local) inner class may be declared as public, protected, private, static, final, or
abstract.
142. What is the difference between the >> and >>> operators?
The >> operator carries the sign bit when shifting right. The >>> zero-fills bits that have
been shifted out.
143. Which method of the Component class is used to set the position and
size of a component?
setBounds()
144. How many bits are used to represent Unicode, ASCII, UTF-16, and UTF-8
characters?
Unicode requires 16 bits and ASCII require 7 bits. Although the ASCII character set uses
only 7 bits, it is usually represented as 8 bits. UTF-8 represents characters using 8, 16,
and 18 bit patterns. UTF-16 uses 16-bit and larger bit patterns.
145. What is the difference between yielding and sleeping?
When a task invokes its yield() method, it returns to the ready state. When a task invokes
its sleep() method, it returns to the waiting state.
146. Which java.util classes and interfaces support event handling?
The EventObject class and the EventListener interface support event processing.
147. Is sizeof a keyword?
The sizeof operator is not a keyword.
148. What are wrapped classes?
Wrapped classes are classes that allow primitive types to be accessed as objects.
149. Does garbage collection guarantee that a program will not run out of memory?
Garbage collection does not guarantee that a program will not run out of memory. It is
possible for programs to use up memory resources faster than they are garbage collected.
It is also possible for programs to create objects that are not subject to garbage collection
150. What restrictions are placed on the location of a package statement within a source code file?
A package statement must appear as the first line in a source code file (excluding blank
lines and comments).