Top 10 tough core Java interview questions answers programming

Tough core Java interview questions and answers

What is tough core

java interview question ? Why do people look for tough Java questions before

going for interview? well I don‘t thing I need to answer these tough questions

because its pretty natural to prepare for tough questions even if you are not

expecting tough questions from core Java. If you are prepare for tough and than you feel more

confident and answer other Java interview question with confidence. On the other

hand if you are not prepare for tough and tricky core Java questions than seeing

them on Java interview or written test may surprise you. But definition of is not universal, same Java question which is easy for

one programmer might be tough for other Java programmer. That‘s why it‘s best to

prepare your own list of tough interview questions before appearing on any Java

job interview. In this article I am going to share you with my <b>Top 10 tough</b>

core Java interview questions and answers, which may help you in Java

interview.

Here is my list of 10 tough or tricky Java interview questions. These

questions are mostly from Core Java and I have not included . As I said you may know answers of these tough Java question or

you may not even find it tough enough to challenge your Java knowledge but once

upon a time these were asked in various Java interview and many programmer

including my friends and colleagues finds them tough to

answer.

<b>Why wait and notify is declared in Object class</b>

instead of Thread ?

Another , how can you answer this question if you are not designed Java

programming language. anyway some common

sense and deep knowledge of Java programming helps to answer such tough core

java interview question. See this blog post to learn  .

<b>Why multiple inheritance is not supported in Java</b>

?

I found this core Java question really tough to answer because

your answer may not satisfy Interviewer, in most cases Interviewer is looking

for specific points and if you can bring them, they would be happy. Key to

answer this kind of tough question in Java is to prepare topic well to

accommodate any follow-ups. See for answer of this tough Java

question.

<b>Why Java does not support operator overloading</b>

One more similar category of  tough Java question. C++ supports

operator overloading than why not Java? this is the argument Interviewer will

give to you and some time even say that + operator is overloaded in Java for

String concatenation, Don‘t be fooled with such arguments. See  for detailed answer of

this tricky Java question.

<b>Why String is immutable in Java?</b>

My

favorite Java interview question, this is tough, tricky but same time very

useful as well. Some interviewer also ask this question as Why String is final

in Java. look at this post for some points which make sense on

<b>Why char array is preferred</b>

to store password than String in Java?

Another which is based on String and believe me there are only few

Java programmer which can answer this question correctly. This is a real

tough core Java interview question and again solid knowledge of String is

required to answer this. see to find out

answer of this tough Java question.

<b>How to create thread-safe</b>

singleton in Java using double checked locking?

This Java question is

also asked as What is

singleton  and how to do you write it. Well Singleton created with double

checked locking before Java 5 was broker and its possible to have multiple

instance of Singleton if multiple thread try to create instance of Singleton at

same time. from Java 5 its easy to . but if interviewer persist with double

checked locking then you have to write that code

for them. remember to use volatile variable.  See for more details on this

topic.

<b></b>

<b>Write Java program to create deadlock in Java and fix it</b>

One of the classical but tough core Java interview question and

you are likely to fail if you have not involved in coding of multi-threaded

concurrent Java application. See  for complete answer of  this

tough core Java interview question

<b>What happens if your Serializable</b>

class contains a member which is not  serializable? How do you fix

it?

Any attempt to Serialize that class will fail with NotSerializableException,

but this can be easily solved by making that variable for static in Java. See for more

details.

<b>Why wait and notify  called from synchronized</b>

method in Java?

Another tough core Java question for wait and notify.

They are called from because wait and modify need monitor on Object

on which wait or notify get called. See  for complete answer of this

tough and tricky Java multi-threading question.

<b>Can you override</b>

static method in Java? if I create same method in subclass is it compile time

error?

No you can not override but its not a compile time error to declare exactly same

method in sub class, That is called method hiding in Java. See  for complete answer of this tough Java

interview question.

These were my list of <b>tough core Java interview</b>

question and answers. Some of the Java question doesn‘t look that tough for

experience programmer but they are really tricky to answer for

intermediate and beginners in Java. by the way if you have faced any tough Java

question in interview then please share with us.

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