Technical interview questions and answers are essential for J2SE Interviews because core Java concepts form the foundation of all Java-based development. Companies test your knowledge of OOP principles, exceptions, packages, JVM architecture, threading, collections, and file handling. These topics commonly appear in placement drives and technical interviews conducted by TCS, Infosys, Wipro, Cognizant, and Capgemini. Understanding J2SE concepts helps freshers and job seekers prepare for both Java developer roles and advanced J2EE/Java EE interviews. This guide features the most commonly asked J2SE interview questions with answers explained in simple language. Preparing these questions will strengthen your Java basics and improve your performance in coding tests and technical rounds.
Java programmers should advance their enterprise skills by studying J2EE frameworks and mastering EJB components for distributed applications
Showing 10 of 237 questions
161. What is overriding ?
Providing a different implementation of a method in a subclass of the class that originally defined the method.
162. What is package ?
A group of types. Packages are declared with the package keyword.
163. What is peer ?
In networking, any functional unit in the same layer as another entity.
164. What is persistence ?
The protocol for transferring the state of a bean between its instance variables and an underlying database.
165. What is pixel ?
The picture element on a display area, such as a monitor screen or printed page. Each pixel is individually accessible.
166. What is POA ?
Portable Object Adapter. A CORBA standard for building server-side applications that are portable across heterogeneous ORBs.
167. What is primary key ?
An object that uniquely identifies an entity bean within a home
168. What is primitive type ?
A variable data type in which the variable's value is of the appropriate size and format for its type: a number, a character, or a Boolean value.
169. What is principal ?
The identity assigned to an entity as a result of authentication.
170. What is private ?
A Java keyword used in a method or variable declaration. It signifies that the method or variable can only be accessed by other elements of its class.