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
121. What method is used to specify a container's layout?
The setLayout() method is used to specify a container's layout.
122. Which containers use a FlowLayout as their default layout?
The Panel and Applet classes use the FlowLayout as their default layout.
123. What state does a thread enter when it terminates its processing?
When a thread terminates its processing, it enters the dead state.
124. What is the Collections API?
The Collections API is a set of classes and interfaces that support operations on collections of objects.
125. Which characters may be used as the second character of an identifier, but not as the first
character of an identifier?
The digits 0 through 9 may not be used as the first character of an identifier but they may be used after the first character of an identifier.
126. What is the List interface?
The List interface provides support for ordered collections of objects.
127. How does Java handle integer overflows and underflows?
It uses those low order bytes of the result that can fit into the size of the type allowed by the operation.
128. What is the Vector class?
The Vector class provides the capability to implement a growable array of objects.
129. 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.
130. What is an Iterator interface?
The Iterator interface is used to step through the elements of a Collection.