Core Java Interview Questions, Answers for Freshers and Experienced asked in various Company Job Interviews

Core Java Interview Questions

Questions Answers Views Company eMail

In the HashMap, we know the values but we dont know the key, then how can we get the key from HashMap ?????

Kanbay,

4 9167

What is Transient and volatile

iFlex,

10 33809

What is the differenc between Enemuration interface and iterator interface according to accessing?

4 8494

what is the difference between static block and static method

Huawei,

19 57843

What is Marker interface in java? and what is clone?

Persistent, Wipro,

16 36637

what is the difference between equals method and ==

IBM, Professional Access, TCS,

17 27833

how many design pattern r there? and wht design pattern u use and why ?

HP,

5 11160

what is the difference b/w PUT and POST method to send data to the server

Mind Tree,

5 14355

In the first round, there are 30 aptitude and 30 java questions. We are suppose to finish both the papers within 60 minutes. I cleared this round. Next was test for programming skills. In this section, Some 7 n's were asked. 1. What is the difference b/w sleep(1000) and wait(1000) 2. what is the diff b/w static block and static function? 3. Write a program to validate IP address using string tokenizer. 4. Write a program to create singleton class 5. write a function to reverse the string 6. Write a prog to print prime nos upto n. EX: If n=9, It shld print 1,2,3,5,7 7. One program on collections- Write a program to print no. of times a number is repeating in an array. EX- {1,3,1,2,5,7,3,7,34,3,8,3} It should print: 1- 2 times 3- 4 times and so on 7. Write a func to print fibonocci series After this I had technical interview, which went on for. 60 mins or so. There were qn's about multi threading, Exception handling and collection classes. Knowledge about collections was very important for the post I was interviewed for.

Huawei,

1 12229

how can i connect to database in a applet ?

1 4938

when to use abstract class and when to use interface?

Exterro, iGate, IonIdea,

16 58721

what is difference between class and object?

College School Exams Tests, HCL,

43 91929

when,where and how to use abstract class and interface

2 5678

explain oops concepts with examples?

AbhiBus, Beeline, DELL, HCL, Satyam, TCS, VLS, Wipro,

29 204584

how can u create the object with out new operator

2 9072

Post New Core Java Questions

Un-Answered Questions { Core Java }

Explain where variables are created in memory?

1014

How does regex work?

967

How to perform bubble sort in java?

996

Does apple use java?

954

What are three advantages of using functions?

1011

What does three dots mean in java?

1127

What is the difference between overriding & overloading?

1072

Which api is provided by java for operations on set of objects?

1461

Can we use this () and super () in a method?

979

What is data object example?

1021

What are the changes in java.io in java 8 ?

1033

What is difference between path and classpath in java?

1027

what is the purpose of using rmisecuritymanager in rmi?

972

Explain illegalmonitorstateexception and when it will be thrown?

1101

What is pojo class in java?

1102

For More Un-Answered { Core Java } Questions Click Here