Tricky Java Interview Questions – A Latest Collection of Tips & Tricks

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1. Tricky Java Interview Questions

Today, we are discussing the last part of our series tricky Java interview questions. These tricky Java interview questions will boost your knowledge and confidence to crack the Java interview in the first attempt. For more detailed knowledge, follow every link provided in tricky Java interview questions.

So, let’s start exploring tricky Java interview questions and answers.

Tricky Java Interview Questions

Tricky Java Interview Questions

2. Interview Questions for Java

Below, we are discussing some important tricky Java Interview Questions:

Q.1 Difference between a class and an object?

An object is an instance or living representation of the prototype whereas a class is a definition or prototype.

Learn more about Java Class & Object.

Q.2 What are the four cornerstones of OOP?

Polymorphism, Abstraction, Encapsulation, and Inheritance.

Q.3 Explain Java’s “write once and run anywhere” Nature?

Java compiles to a bytecode, the intermediate language between source code and machine code. This bytecode doesn’t platformed specific and hence often fed to any platform.

Q.4 How to restart a Dead Thread Be?

A dead thread can’t be restarted.

Q.5 What happens if an exception not caught?

It leads to the termination of the program within which through when an uncaught exception results in the uncaughtException() method of the thread’s ThreadGroup, it invokes.

Q.6 Describe a compilation unit?

A Java source code file.

Q.7 Explain a task’s priority and also tell how it is used in scheduling?

An integer value is the priority of a class that identifies the relative order in which it should be executed with respect to other tasks. The scheduler tries to schedule higher priority tasks before lower priority tasks.

Q.8 State the value which will Readline() return once it’s Reached the tip of a file?

Returns null once it reaches the end of a file.

Q.9 When will an object’s Finalize() method Invoke?

An object’s finalize() method can’t invoke by the garbage collector whereas the thing continues to be reachable. However, an object’s finalize() method could also invoke by different objects.

Tricky Java Interview Questions for freshers – Q. 1,2,3,4,6,8

Tricky Java Interview Questions for experienced – Q. 5,7,9

Q.10 Will garbage collection guarantee that a program won’t run out of memory?

Garbage collection doesn’t guarantee that a program won’t run out of memory. It’s possible for programs to use up memory resources quicker than they’re garbage collected. It’s also possible for programs to make objects that don’t subject to garbage pickup.

Q.11 Is Sizeof a keyword?

The sizeof operator isn’t a keyword.

Q.12 What state will a thread enter once it terminates its processing?

When a thread terminates its processing, it enters the dead state.

Let’s discuss Tricky Java Interview Questions Part 2, Part 3, Part 4

Q.13 Will a lock acquire on a class?

Yes, a lock often acquires on a class. This lock acquires on the class’s class object.

Q.14 How to use observer and Observable?

Objects that subclass the Observable class maintain a list of observers. An observable object once when update it invokes the update() method of every one of its observers to advise the observers that it’s changed state.

Q.15 What’s s transient variable?

A transient variable may a variable that will not serialize.

Q.16 What is the Output From System.out.println(“hello”+null);?


Q.17 What are E and Pi?

E is the base of the natural logarithm and PI is mathematical value pi.

Tricky Java Interview Questions for freshers – Q. 10,11,12,15,16,17

Tricky Java Interview Questions for experienced – Q. 13,14

Q.18 If an object is garbage collected, will it become reachable again?

Once associate degree object is garbage collected, it ceases to exist. It will not become reachable again.

Q.19 Will an exception is rethrown?

Yes, an exception often rethrown.

Q.20 What’s the purpose of the file class?

The File class use to make objects that give access to the files and directories of a local file system.

Q.21 Is a class subclass of itself?

No. a class isn’t a subclass of itself.

Q.22 What modifiers may use with an interface declaration?

An interface may declare as public or abstract.

Q.23 What classes of exceptions may catch by a catch clause?

A catch clause will catch any exception that will allot to the Throwable kind.

Q.24 Tell us the difference between the reader/writer class hierarchy and also the Inputstream/outputstream class Hierarchy?

The InputStream/OutputStream class hierarchy is byte-oriented and the reader/writer class hierarchy is character-oriented

Q.25 Will an Object Garbage Collected whereas it’s Still Reachable?

A reachable object can’t garbage collected. Solely unreachable objects may garbage collected.

Tricky Java Interview Questions for freshers – Q. 18,19,20,21,22,13

Tricky Java Interview Questions for experienced – Q. 24,25

3. Conclusion

Hence, you have completed the last part of our series tricky Java Interview Questions. Hope, these frequently asked tricky Java Interview Questions helped you to make your career brighter. Still, if any doubt regarding tricky Java Interview Questions, ask in the comment tab.

See also-

java Interview Questions Part 5, Part 6, Part 7

For reference

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3 Responses

  1. Nikhil says:

    Helpful Post! Thanks for sharing the valuable Java Interview Questions and Answers.This article will help me to prepare for the interviews and very helpful post for freshers.Thanks for sharing this list of questions with answers. I found this is a very informative article. keep sharing.

    • DataFlair Team says:

      Hi Nikhil,
      Thank you for giving us a chance to serve you with our best study material. It’s very nice to hear that our Tricky Java Interview Questions are helping you with your interview.
      You can check out our sidebar there is a series of interview questions and quizzes. We are sure they will also help you.

  2. Sushma Deyannavar says:

    thank you for giving chance to learn in dataflair. its very nice to solve the interview questions for more confidential for myself.

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