Interview Questions and Answers for 'Java' | Search Interview Question - javasearch.buggybread.com
Javasearch.buggybread.com

Search Interview Questions


 More than 3000 questions in repository.
 There are more than 900 unanswered questions.
Click here and help us by providing the answer.
 Have a video suggestion.
Click Correct / Improve and please let us know.
Label / Company      Label / Company / Text

   



Interview Questions and Answers - Order By Newest

   next 30
 Q321. Interface can only have ...

a. Member elements and Methods.
b. Static Variables and Static Methods.
c. Static Final Variables and Instance Method Declarations.
d. Member Elements , Instance Methods, Static variables and Static Methods.
Ans. Static Final Variables and Instance Method Declarations.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     java   oops   interfaces

 Q322. Which of the following collection maintain its elements in Natural Sorted order ?

a. HashMap
b. TreeMap
c. LinkedHashMap
d. LinkedMap
Ans. TreeMap

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     treemap   collections   java   sorted collections   map

 Q323. If we try to add duplicate key to the HashMap, What will happen ?

a. It will throw an exception.
b. It won't add the new Element without any exception.
c. The new element will replace the existing element.
d. Compiler will identify the problem and will throw an error.
Ans. The new element will replace the existing element.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     hashmap   map   collections   java

 Q324. Which of the following exception is thrown when we try to access element which is beyond the size ?

a. NullPointerException
b. ArrayIndexOutOfBoundException
c. ArithmeticException
d. ParseException
Ans. ArrayIndexOutOfBoundException

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     java   exceptions   error handling

 Q325. Checked exception needs to be ...

a. Caught
b. Method needs to declare that it throws these exception
c. Either A or B
d. Both A and B
Ans. Either A or B

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     java   exceptions   checked exceptions

 Q326. Which of the following is not valid var args declaration ?

a. int sum (int... numbers)
b. int sum (.int .. numbers)
c. int sum (int ... numbers)
d. int sum (int x, int ... numbers)
Ans. int sum (.int .. numbers)

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     java   var args
Try 2 Question(s) Test

 Q327. Which of the following keyword is not permitted for outer class ?

a. public
b. abstract
c. final
d. protected
Ans. protected

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     java   java keywords

 Q328. Which java frameworks have you used ?General
Ans. I have primarily worked on Web applications and hence worked on Struts , Spring , Hibernate, JSF ( Java Server Faces ) , Velocity etc.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     elsevier   frameworks   java frameworks   general question     Asked in 3 Companies      basic        frequent

  Q329. How are values passed in Java ? By value or reference ?Core Java
Ans. Java only provides pass by value.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     ebay   pass by value   pass by reference   method call   methods   functions   function call     Asked in 10 Companies      basic        frequent

Recently asked in Capital One.
 Q330. What will happen if we call perform(null) ?

public void perform(Object obj) {
System.out.println("Object");
}

public void perform(Integer int) {
System.out.println("Integer");
}		Core Java
Ans. compiler will throws error as ambiguous methods

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     overloading   method overloading     Asked in 1 Companies      intermediate

 Q331. What is a package and what are its advantages ?Core Java
Ans. Package is a namespace that organizes a set of related classes.

Advantages of Packages

1. Better Organization of classes.
2. Saves from the problem of duplicate names as duplicate class names are allowed across different packages.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     package  advantages of packages     Asked in 1 Companies      Basic

 Q332. What was the driving force to introduce default methods in Interfaces wef from Java 8 ?Core Java
Ans. Earlier any class implementing an interface was supposed to implement all methods declared in an interface. There was no place for optionally implementing all or subset of methods.Though we have abstract classes wherein we could have provided such a mechanism by declaring some methods as abstract while providing definition for some. But as Abstract classes have a body and are comparatively heavier than interfaces and interfaces associate closely to the concept of providing interfacing than abstract classes, Java might have though of providing optional implementation for default methods. This way same interface can be reused in variety of ways rather than making copies of an interface to suit different needs.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     java 8   java8  interface default methods  default methods     Asked in 6 Companies

 Q333. What is System.in in Java ?Core Java
Ans. It is an InputSream which is usually connected to the keyboard input of console program.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     System.in  Input Stream  Input Output

Frequently asked.
 Q334. When does the finally block gets executed ?Core Java
Ans. A finally block of code always executes, whether or not an exception has occurred.The only time finally won't be called is if you call System.exit() or if the JVM crashes first.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     finally  exception handling  exceptions     Asked in 4 Companies      basic        frequent

 Q335. How do you prefer to store money values in your application ?Core Java
Ans. At Application level we use either Double or BigDecimal , preferably BigDecimal. At Database level we use Number with decimal precision 3.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     data types

 Q336. Explain System.out.println ?Core Java
Ans. System is a class within java.lang package that contains several useful class fields and methods. It cannot be instantiated and hence can use only statically.even in this case this has been used statically i.e with class name itself and without creating an instance.

out is the static reference of Printstream declared as following in the System Class -

public final static PrintStream out = null;

println is the method of PrintStream class.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     System class  Streams  Input Output  println     Asked in 1 Companies      basic        frequent

 Q337. Implement the following method ?

int findMax(int[] items)
Core Java
Ans. int findMax(int[] items){
   int maxNumber = 0;
   for(int x:items){
      if(x > maxNumber){
         maxNumber = x;
      }
   }
      
   return maxNumber;
}

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     coding  code  find max number in an array     Asked in 1 Companies

 Q338. If everything is an object , Cant we declare every object as

Object obj = new String();		Core Java
Ans. Yes, we can do that. Compiler wont complain. But using object reference we can only access methods which have been defined for object class i.e clone(), equals(), hashCode(), toString() etc.

We cannot access methods defined in String class or in any class in hierarchy between String and Object.

For example - we cannot do obj.append("abc") as it will now give compile time error.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     object initialization  object declaration   runtime polymorphism  object oriented programming (oops)  oops concepts

 Q339. Which type of memory is cleaned / recovered by garbage collection - stack or heap ?Core Java
Ans. Heap memory.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     memory management  stack  heap  garbage collection     Asked in 2 Companies

 Q340. Write a program to print all even numbers first and then all odd numbers till 100. For example the output should be
2
4
6
8
...... 100
and then
1
3
5
7
...... 99

using only 1 for loop ? Is it possible with just one loop ?		Core Java
Ans. Yes , It can be done using single for loop

public class BuggyBread{
public static void main (String args[]) {
   int x = 50;
   for(int i=1;i <= 100;i++){
      if(i<=50){
         System.out.println(i*2);
      } else {
         System.out.println(i-x);
         x = x - 1;
      }
   }
}
}

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     code  coding     Asked in 1 Companies

 Q341. Given two files with list of words, write a program to show the common words in both filesCore Java
Ans. import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.io.*;
public class Common {
public static void main(String ar[])throws Exception
   {
      File f=new File("a.txt");
File f1=new File("x.java");
      System.out.println(f.exists());
FileInputStream fin = new FileInputStream(f);
      FileInputStream fin1 = new FileInputStream(f1);

      byte b[]=new byte[10000];
byte b1[]=new byte[10000];
fin.read(b);
fin1.read(b1);
String s1 = new String(b);
String s2 =new String(b1);

String words1[] = s1.trim().split(" ");
String words2[] = s2.trim().split(" ");
Listlist1 = new ArrayList<>(Arrays.asList(words1));
Listlist2 = new ArrayList<>(Arrays.asList(words2));
list1.retainAll(list2);
System.out.println(list1);
}
}

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     file handling  file io  code  coding     Asked in 1 Companies

 Q342. What is the difference between for and foreach loop in java ? Which one should be used in which cases ?

Core Java
Ans. 1. for loop in java is used with a counter as following

for(int counter=0;counter < 50;counter++){
System.out.println(list.get(counter));
}

for iterating and printing the contents of a collection

whereas foreach loop can be specified directly without the use of counter

for(String str:list){
System.out.println(list.get(counter));
}

2. for Each loop syntax is more clean if we have to iterate over the elements of a collection and we need not keep track of the record count

3. For is preferred when we need loops without the usage of collections or Array of objects and entirely primitives are being used

4. for loop is preferred if we need to keep track of record count and have to perform some action of the basis of that. For example - If we have to print something after every 5 records, With for each loop in such case, we will have to keep a separate counter.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     loop  for loop  control statements  loop statement  foreach loop  for vs foreach loop

 Q343. Does java supports operator overloading ?Core Java
Ans. No

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     operator overloading     Asked in 1 Companies      basic

 Q344. When is the situation when finally section won't execute ?Core Java
Ans. If the process / app is abruptly killed or terminated.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     exception handling  finally     Asked in 2 Companies      intermediate
Try 1 Question(s) Test

 Q345. What is the use of static keyword in Java ?Core Java
Ans. static keyword is used to specify that the respective programming construct ( method , variable ) belongs to the class and not to its instance and is supposed to be shared by all instances of the class.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     static keyword     Asked in 1 Companies      basic        frequent

 Q346. Is it a good practice to use Asterick(*) in import statement to load multiple packages with single import statement ?Core Java
Ans. No, we should be lean in loading only packages which are required. Loading packages which are not being used result in memory overheads.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     import  import packages     Asked in 1 Companies

 Q347. What is a Servlet Filter ?Java EE
Ans. It's an object that can intercept http request and response and hence we can take appropriate action on those requests.

There are different types of filters based on Specifications like

Authentication
Logging
Encryption
Tokenizing

etc

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     servlets  servlet filters     Asked in 3 Companies      basic        frequent

 Q348. Can we override wait() or notify() methods?Core Java
Ans. wait and notify are declared final in object class and hence cannot be overridden.

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     object class methods  wait  notify

 Q349. Write a multi threaded Program that will simulate transferring of money across accounts ? Core Java
 This question was recently asked at 'Trustwave'.This question is still unanswered. Can you please provide an answer.


 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve          Asked in 1 Companies

 Q350. Write a Program to print factorial of a number using recursionCore Java
Ans. public class BuggyBread {
public static void main(String args[]) {
System.out.println(factorial(5));
}

private static int factorial(int number){
if(number == 1){
return 1;
} else {
return number * factorial(number - 1);
}
}
}

 Help us improve. Please let us know the company, where you were asked this question :   

   Like         Discuss         Correct / Improve     recursion     Asked in 25 Companies

previous 30   next 30

Help us and Others Improve. Please let us know the questions asked in any of your previous interview.

Any input from you will be highly appreciated and It will unlock the application for 10 more requests.

Company Name:
Questions Asked: